|UFDC Home||myUFDC Home | Help|
This item has the following downloads:
1 FRAMEWORK FOR INTEGRATION OF BIM AND RFID IN STEEL CONSTRUCTION By WEI SHI A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA 2009
2 2009 Wei Shi
3 To my parent Yongling Shi and Shuzhen Lei, my wife Haiyan Xie, my son Owen Shi and daughter Catherine Xie Shi
4 ACKNOWLEDGE MENTS First of all, I would like to express my sincere appr eciation to Dr. R. Raymond Issa for his kind help throughout my study and life at the University of Florida. He is not only my supervisor but also a great mentor. I am so glad to have him as the C hairman of my Ph.D. committee. His inspiring enthusiasm and energy have been contagious and his encouragement and support have been extremely helpful. I also want to thank Dr. Robert C. St r oh, Dr. Svetlana Olbina, Dr. Ajay Shanker, and Dr. Randy Chow for their service on my Ph.D. Committee. Without their knowledge and advice it would have been impossible to finish my dissertation I would like to express my deepest love to my wife Haiyan Xie. She did a wonderful job to take care of our famil y. I thank G od for bringing us together in Holy matrimony. I thank my so n Owen Shi and daughter Catherine Xie Shi, for their love. They are very good kids for their age groups and have suffer ed many sorrow ful days for miss ing their Dad Specifically, my greatest gratitude goes to my parents Yongling Shi and Shuzhen Lei They have always support ed us and have give n their endless love to my kids. They took care both of my kids from their b irth until they became three year s old so that we c ould have more time to focus on our study and our work.
5 TABLE OF CONTENTS page ACKNOWLEDGEMENTS .............................................................................................................4 LIST OF TABLES ...........................................................................................................................8 LIST OF FIGURES .........................................................................................................................9 ABSTRACT ...................................................................................................................................11 CHAPTER 1 INTRODUCTION ..................................................................................................................13 Motivation ...............................................................................................................................13 Challenges ...............................................................................................................................14 Research Problem ...................................................................................................................15 2 LITERATURE REVIEW .......................................................................................................17 B ackground .............................................................................................................................17 Steel Structures Concepts and Components ...........................................................................18 Design of Steel Structures ...............................................................................................18 The T ypes and S hapes of S tructur al S teel .......................................................................19 Control of Quality ............................................................................................................20 Drawing and Codes .........................................................................................................20 Engineer drawings and w orkshop drawings .............................................................20 Steel l ayout and design the shop drawings ...............................................................21 Marks for erection and c onnection special marks ....................................................21 Steel S tructure S upply C hain ...........................................................................................22 Mill Fabrication .......................................................................................................24 Pre Erection with contractor or subcontractor .........................................................24 Erection plan ............................................................................................................25 Sequences of F abr ication and E rection ...........................................................................25 The T echnique D eveloped and U s ed in S teel S tructure ..................................................26 Web based Project Management ............................................................................................28 Visualization and VRML ........................................................................................................28 Building Information Modeling (BIM) ..................................................................................29 Manufacturing Systems Integration (MSI) .............................................................................35 BIM on Site .............................................................................................................................38 Steel Identification with RFID ................................................................................................40 CIMSteel Integration Standards (CIS/2) ................................................................................52 General Decision Making Model Description ........................................................................55 Decision Making Environments and Decision Criteria ...................................................57 Decision Making Generation ...........................................................................................60
6 3 METHODOLOGY .................................................................................................................63 Objective of Research .............................................................................................................63 Modeling and Implementation ................................................................................................64 Verification and Testing .........................................................................................................64 Problems Release and Discussion ..........................................................................................65 Case Study Design ..................................................................................................................66 Contributions to the Construction Industry ............................................................................68 4 BIM/RFID FRAMEWORK ANALYSIS ...............................................................................69 Decision N eed for T ypical S tructure P roject ..........................................................................69 In the D esign S tage ..........................................................................................................69 In the F abrication S tage ...................................................................................................75 In the D elivery S tage .......................................................................................................78 In the J ob S ite E rection S tage ..........................................................................................79 Components of the BIM/RFID Framework ............................................................................81 RFID Integration in the Proposed System .......................................................................85 RFID and GPS on Site to Improve BIM Functions .........................................................90 5 BIM /RFID FRAMEWORK IMPLEMENTATION ...............................................................94 BIM/RFID Framework Description .......................................................................................95 BIM/RFID Framework Components and Relationship ..........................................................98 T he Process of BIM Implementation ......................................................................................99 BIM/RFID Framework .........................................................................................................103 BIM Data Base ..............................................................................................................103 BIM Testing ...................................................................................................................104 BIM Model Base ...........................................................................................................104 BIM/RFID Framework Implementation for Steel Structure Project ....................................105 Knowledgeable BIM Team ...........................................................................................105 Using RFID in the BIM/RFID Framework ...................................................................105 Using RFID for Steel Structure Design .........................................................................107 How the RFID Works in a Steel Structure ....................................................................108 BIM/RFID Framework Layout ......................................................................................109 An Example of RFID Works in Steel Member .............................................................118 6 CASE STUDY ......................................................................................................................123 Case Study OCW Building ................................................................................................123 How RFID Creating an Erection Order .........................................................................130 RFID and 4D Simulation for Crane Plan ......................................................................131 RFID and BIM Controlling Delivery Ontime ..............................................................131 RFID BIM Zoning .........................................................................................................133 Case Study S Steel Company ............................................................................................136 Background ....................................................................................................................136 Task and Plan ................................................................................................................136
7 Re organization for a BIM Model Base Com pany Structure ........................................138 The BIM Model Cost and Implementation ...................................................................140 BIM Brings Benefits to S Steel Company .....................................................................141 RFID Potential Usage ....................................................................................................142 Feasibility Analysis of BIM for S Steel Company ........................................................142 Example of S Steel Workflow Using BIM/RFID Framework ......................................143 Time Based Supply Chain Management On time Delivery ........................................145 Erection Sequence Analysi s Optimized Schedule .......................................................148 Summary ...............................................................................................................................154 7 CONCLUSIONS AND RECOMMENDATIONS ...............................................................156 Research Summary and Contribution ...................................................................................156 Limitations and Barriers of the BIM/RFID Framework .......................................................157 Database Problems ........................................................................................................157 Lack of data access .................................................................................................157 Data safety problem ...............................................................................................157 Data reliability ........................................................................................................158 Visualization Quality Transaction and Transfer Confliction ........................................158 Field Operations Internet and Network Limitation .......................................................158 Safety Control Still Depends on Human Responsibility ...............................................159 Recommendations for Future Research ................................................................................159 APPENDIX A SAFETY STANDARDS FOR CONSTRUCTION WORK ................................................162 B SITE SPECIFIC ERECTION PLAN AND CHECK LIST ( EXAMPLE FORM) ..............193 C Steel STRUCTURE DESIGN TABLES (AISC) (HARWARD 1989) ................................198 LIST OF REFERENCES .............................................................................................................200 BIOGRAPHICAL SKETCH .......................................................................................................205
8 LIST OF TAB LES Table page 11 Cost of inadequate i nteroperability by Stakeholder Group by Life Cycle Phase (in $ Millions) (NIST 2005) ....................................................................................................15 21 Comparing BIM and t raditional documentation (Leicht and Messner 2007) ....................33 22 RFID performance a dvantages and d isadvantages ............................................................42 23 RFID specification and concepts (http://data acquisition.globalspec.com 2008) .............43 24 Applications of s ystems for e ach o rganizational l evel (Laudon 1998). .............................59 41 Decision s needed for a typical steel structure project ........................................................70 42 Integration of RFID technology by steel frame building design and construction comp anies ..........................................................................................................................87
9 LIST OF FIGURES Figure page 21 Web base Project Management (by Avolve Soft ware) .....................................................28 22 Virtual Reality a rchitecture ................................................................................................29 23 The f unction differences between BIM and tradition al documents (Leicht 2007) ............32 24 4D Model created by BIM .................................................................................................34 25 Computer i ntegrated c onstruction t echnology f ramework (Xie 2005) ..............................38 26 VRML model with several display features (Lipman and Reed 2003) .............................47 27 RFID c oding s ystem w orkflow ..........................................................................................50 28 General d ecision making processes ...................................................................................57 29 Configuration dialog generation m anagement s ystem of a DSS Generator (Sprague 1982) ..................................................................................................................................61 31 Model s elections and s olution process ...............................................................................66 41 BIM and s upporting b ases .................................................................................................82 42 Systems relationship with decision making frame .............................................................84 43 BIM functions in project m anagement c oncept .................................................................85 44 Steel e rection c omponents .................................................................................................90 45 Examples of RFID and GPS use in s teel s tructure e rection (Ergen 2006) ........................92 51 RFID used for BIM components ........................................................................................96 52 Process of external data connection to an OLAP system (Xie 2005) ................................98 53 BIM /RFID framework c omponents and r elationship ......................................................100 54 Traditional e rection f low c hart .........................................................................................102 55 BIM/RFID Framework a rchitecture ................................................................................103 56 BIM/RFID Frame work network ......................................................................................105 57 RFID using Data flow for BIM/RFID Framework decision making process ..................107
10 58 RFID data reading in site .................................................................................................109 59 RFID a pplication paths ....................................................................................................110 510 RFID data i mplementation f lowchart ..............................................................................112 511 4D BIM Model shows a column with RFID changes (Revit 2008) ................................119 512 Tradition RFI or RFC versus RFID jobsite flowchart .....................................................122 61 The BIM/RFID and tradition al methods process for a steel structure project .................125 62 Project files transfer architecture .....................................................................................126 63 BIM/RFID Framework for optimal erection plan ............................................................129 64 Detail of RFID database creating erection order plan .....................................................130 65 D etail of RFID creating a crane plan ...............................................................................132 66 Detail of RFID creating a delivery BIM on time plan .....................................................132 67 RFID data flow during de livery .......................................................................................133 68 Detail of RFID creating BIM zoning for safety plan .......................................................135 69 Sketch map of BIM zoning safety control .......................................................................135 610 S Steel Company organization structure chart .................................................................137 611 S Steel Company simulation of using BIM organization structure chart ........................139 612 BIM work flow for S Steel fabrication and erection process ...........................................144 613 Tradition construction method versus BIM/RFID Framework schedule and delivery flow ..................................................................................................................................151 614 The simulation of BIM/RFID Framework operation for steel structure erection job sequences (AISC 2005) ....................................................................................................152 71 Traditional construction versus BIM current and future planning and organization .......160
11 Abstract of Dissertation Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy FRAMEWORK FOR INTEGRATION OF BIM AND RFID IN STEEL CONSTRUCTION By Wei Shi December 2009 Chair: R. Raymond Issa Major: Design, Construction and Planning The construction industry faces the challenge of synthesizing information and deriving insight from massive, dynamic, ambiguous and possibly conflicting digital data. A variety of data models and algorithms have been proposed and implemented to examine data, acquire information, and derive understanding from the information. Those models, systems, and implementations usually foc us on one or several aspects of the design, procurement, construction, and maintenance phases of a project. Construction professionals often face situations where they have to select or combine the best options to improve the accuracy and certainty of the decision making process. Building Information Modeling ( BIM ) is a combination of all the project data, displayed in a designed systematic model. Examples of those systems include interact ive design systems, decision support systems, expert systems, knowledge based systems, virtual reality and 3D simulations. There are high requirement s to the steel iron worker personal skills for steel connections, which limits the innovation of steel ere ction methods and management. Project manager needs to make decisions on the arrangement of subcontractor work sequences, project control safety and quali ty.
12 The focus of this research is to investigate and develop the framework of using Radio Frequency Identification (RFID) and BIM for the decisionmaking process in steel construction. It aims to maximize functions software and hardware and to improve compatibility of those software and database used in construction projects by using BIM/RFID system In this research, Building Information Modeling (BIM) and RFID deal with structural steel fabrication and erection to develop a portable RFID database which can assist steel fabrication and erection efficiency and accuracy RFID and BIM integration wit h Manufacturing Systems Integration (MSI) make a framework for help ing user s in making decisions when dealing with numerous fabrication and erection job conditions The significance of the propos al framework is in helping user to select a optimal plan for fabrication, delivery and erection; enabling data stakeholders to detect the expected information and discover the unexpected situations in massive data sets; developing a BIM zoning plan for jobsite safety control; and describing a RFID and GPS future position system. .
13 CHAPTER 1 INTRODUCTION Motivation Over the past decade advanced uses of information technology (IT) in construction have become more commonl y accepted by most construction firms. The implementations of information technology (IT) in construction management have undergone rapid developments. These implementations have related to a multitude of hardware, software, and networks with the functions of storing, transferring, processing and presenting information. General technologies, such as semantic modeling, data mining, mobile technologies, or domainoriented ones, i.e. e commerce, collaborative websites, or digital mock ups, have revealed a great spectrum of potential in the construction industry. Information technology helps in the sharing of information and in advancing collaboration among project teams. The implementation of IT in the construction industry can be used in many situations. For e xample, projects are being designed and managed by teams located in different countries; design or engineering is being outsourced and completed in collaborative fashion; cameras and sensors are used to continuously monitor in real time the state of infrastructures and buildings. The majority of IT software was developed by independent companies without cooperation or sharing resources. The software developers secured their information and commercial secrets by fencing their properties, so that they coul d keep their market advantage longer. But this type of software development approach causes interoperability problems for endusers in other industries that do not have IT support teams. A recent NIST (National Institute of Standard and technology ) study, as shown in Table 1 1, indicated that the cost of inadequate interoperability in the U.S. capital facilities industry to be $15.8 billion per year. The intended audiences are owners and operators of capital facilities; design, construction, operation and m aintenance, and
14 other providers of professional services in the capital facilities industry; and public and private sector research organizations engaged in developing interoperability solutions (NIST 2005). These firms face the challenge of combining soft ware from different sources, to make the software adapt to different operations or to solve the conflicts with the existing software environment. This is the IT bottleneck faced by construction companies and software developers. Challenges The constructio n industry, as well as other industries, faces the challenge of synthesizing information and deriving insight from massive, dynamic, ambiguous and possibly conflicting digital data. A large variety of data models and algorithms have been proposed and imple mented to exam data, acquire information, and derive understanding from the information. Those models, systems, and implementations usually focus on one or several aspects of the design, procurement, construction, and maintenance phases of a project. With the multitude of the interactive design systems, decision support systems, expert systems, knowledge based systems, virtual reality and 3D/4D simulations, a construction professional faces the situation of how to select or best combine the available options to improve the accuracy and certainty of the decisionmaking process. Innovation is the key to keep the modeling industry advancing. Management has been the most important asset in every firm. Looking back at model management innovator Frederick Taylor, it is noted that his single minded devotion to efficiency stemmed from a conviction that it was iniquitous to waste even an hour of human labor when a task could be redesigned to be performed more efficiently. Taylor could spend days studying the most productive ways to shovel coal were evidence not only of an obsessive mind, but of a missionary zeal for multiplying the value of human effort. (Hamel 2007) Specifically, the adoption of IT in a construction company should help steer the business and facilita te effective decision making.
15 Table 11. Cost of inadequate i nteroperability by Stakeholder Group by Life Cycle Phase (in $ Millions) (NIST 2005) Stakeholder Group Planning, Engineering, and Design Phase Construction Phase Operations and Maintenance Phase Total Architects and Engineers 1,007.2 147.0 15.7 1169.8 General Contractors 485.9 1,265.3 50.4 1,801.6 Specialty fabricators and Suppliers 442.4 1,762.2 2,204.6 Owners and Operators 722.8 898.0 9,027.2 10,648.0 Total 2,658.3 4,072.4 9,093.3 15,824 .0 Source: RTI estimates. When users collect and examine data in models or systems, the goals are to retrieve information, to derive understanding from the information, and to facilitate effective decisionmaking. For effective decision making, informat ion needs to be collected from multiple categories or disciplines F or the heterogeneous data from various data sources, there are discussions about the systematic ways or methods for information retrieval, evaluation, qualityassessment, and analysis. A ll these procedures of information treatment serve the purpose of finding the optimized the solution to the practical problems in real world. All these require interdisciplinary research collaboration with the focus on analytical reasoning facilitated by int eractive visual interfaces. Research Problem There are high requirement s to the steel iron worker personal skills for steel connections, which limits the innovation of steel erection methods and management. In addition, variances of iron workers perform ances bring in lots of job mistakes and safety accidents. Erectors need to make decisions on the steel connections, equipment selections, labor arrangements, operation, and loading problems. Project manager needs to make decisions on the arrangement of subcontractor work sequences, project control safety and quali ty. In order to solve these problems, many software companies have developed BIM tools for construction use. These BIM tools have integ ration problems and may conflict when used together for a si ngle project.
16 The focus of this research is to investigate the framework of BIM/RFID to assist decision making in construction project manage ment. This research proposes to use information visualization in steel structure projects to display a model of using web based RFID and real time 4D BIM and MSI for the steel fabrication and erection sequence. It aims to maximize functions software and hardware and to improve compatibility of those software and database used in construction project s by using BIM/ RFID system This study would show how the structural steel identification system, such as RFID, w ould combine BIM and MSI to reduce mistakes in steel fabrication and erection It helps to control multi duty projects easier.
17 CHAPTER 2 LITERATURE REVIEW Background This chapter discusses the current trends in the construction I nformation T echnology (IT) research and the industry needs. The litera ture review will first discuss the web based project management in the construction industry. Then this chapter is going to discuss : virtual reality modeling (VRML), Industry Foundation Classes (IFC), CIS/2, Building information Modeling (BIM) and Revit, R adio Frequency Identification (RFID), the 4 D Project (Navisworks), Manufacturing System Integration (MSI) and data visualization techniques. Based on the understand ing of these concepts, this research will develop a model for combining these systems in a BIM/RFID framework to assist fabrication and erection in the construction of steel structures. Currently BIM software can be used to generate visual representation s for construction projects, but BIM models cannot be used to develop and store the whole pr oject information. The use of advanced management methods together with system integration techniques should give project manager s better tools to accomplish their tasks. T here are several trends in Information Technology (IT) in modeling design that aff ect the construction industry. Examples include construction software for design and development purposes to be more specific, those software products include professional specification software or construction scheduling and estimating software. Other examples include web based construction project management software; simulation by using computer visualization models; and BIM. These software products are updated frequently. Intense competition pushes software developers to improve their designs and make their software more functional and user friendly.
18 Steel Structure s Concept s and Components Design of Steel Structure s During t he development of iron and steel as engineering materials, material testing showed the advan tages of using these materials in structur al analysis and design. The features of these materials made it possible to transit the str ucture design from state of art to applied science. It was Hooke (1660) who developed the concept that load and deformation were proportional, and Bernoulli (1 705) introduced the concept that the resistance of a beam in bending is proportional to the curvature of the beam. Bernoulli passed this concept on to Euler, who in 1744 determined the elastic curve of a slender column under compressive load. In the 1800s, i mportant developments in steel structure design included: (1) Manufacture of mechanical strain measuring instruments that made possible the determination of the elastic modulus that related stress to strain, (2) Correct theories for the analysis of stres s and deformation resulting from either the bending or twisting of a structural member, and (3) The extension of column bucking theory to the bucking of plates and the lateral torsion bucking of beams. (Johnson 1974) The above mentioned advantages of steel enabled the development of engineering specifications built around the allowable stress methods of selecting structural members. The first general specification for steel railway bridges was developed in 1905 T he first highway bridge specification was de veloped in 1931. In 1923 the AISC (American Institute of Steel Construction) published its first general specification for building construction. Under each of these specifications, the process and criterion of acceptable design are as follows: first, calcula ting maximum stress; secondly, assuming elastic behavior up to anticipated maximum loads ; thirdly, keeping actual stress lower than a specified allowable stress. The allowable stress is intended to be less than the stress causing failure by a factor of safety.
19 During the past half century, AISC has developed the design factors to standardize the design of steel structure, to evaluat e the inelastic properties of materials, and to direct ly calculat e the ultimate strength of a member. L oadfactor design an d other design features can be calculated as the result s This is a realistic, direct, and natural procedure. The load factor approach has been used for many years in aircraft design. Part 2 of AISC introduced the loadfactor design in 1961. This approach is an acceptable alternative to the allowable stress procedures for the design of continuous frames in building structures. S teel structure design and construction include: manufacturing, fabricating connecting, delivering and erection. Safety issue is critical in the whole process of steel structure design and construction. Structu ral steel construction safety is a result of careful design, well fabrication arrangement, construction methods and management. In the design process, t he risk of failure is evaluated and the probability of its occurrence is kept at an acceptable level The exact number of the safety factor d epends on the importance of the structure, risk to human life and other factors. Evaluation of safety uses these factors. Variable or u ncertain loads, such as those due to wind, flood, and earthquake are also consider ed for the evaluation of safety The T ypes and S hapes of S tructur al S teel A s tension members, structural steel items basically ha ve seven shapes: a ngle, t ee, W/S/M shape, pip e, double angle and double channel ( s ingle plane truss members), build up plate and angle shape ( double plane truss). Columns and compression members use difference types: r ound and solid bars, s teel pipes, box s ection and s tructure t ubes, angle s truts, s t ructure t ees, w ide f lange s hapes, c olumns with l acing, battens, or perforated c over plates. There are three types of steel which are normally called for construction: m ild s teel, h igh tensile steel and weather resistant steel. Different grades mean various steel types which are included in reference manual.
20 Control of Quality A s a part of the quality control system, standards are usually adopted by agreement of trade associations O fficial and semiofficial standards are organized by t he National Bureau of Standards, the Department Commerce, and a network of engineering testing laboratories and inspection services spread throughout the country. These originations are not only controlling the quality of steel structure, but also keep ing the improvement of st eel structure technology. The following are some organizations related to structural steel standards: ASTM American Society for Testing and Materials, AISC American Institute of Steel Construction, AWS The American Welding Society, ICBO The International C onference of Building Officials, AISI The American Iron and Steel Institute, AASHTO American Association of State Highway and Transportation Officials, ANSIAmerican National Standards Institute, AREA American Railway Engineering Association, API American Petroleum Institute, Etc. Drawing and Codes Code and design specifications are a part of the professional and societal system for regulating construction. E ngineer s must understand them as both constraints and tools in design practice. The 1982 Uniform B uilding Code consist ed of 48 chapters and 14 chapter of appendix (1982UBC). Codes and specifications attempt to define minimum acceptable levels of safety and translate them into design constraints. Engineer drawings and w orkshop drawings Engineer drawing s are the drawings which describe the e ngineer s requirements and show steelwork in an assembled form. Usually they give all leading dimensions of the structure including alignments, levels, clearances, member size, and steelwork in an assembled form. The purposes of e ngineer drawings are: (1) to create a bas is for the engineer s cost estimate before tenders are invited; (2) t o invite tenders upon which competing contractors base their
21 prices ; (3) to i nstruct the contractor during the contract including a ny revisions and variations ; (4) to make progressive payments for the contractor based on the work completion. Workshop drawings are defined as the drawings prepared by the steel contractor showing each and every component or member in full details for f abrication. Steel l ayout and design the shop drawings Specifications give the simple and precisely direction to the procedures for the design of main members, such as beams, columns, and tension members. S tructural engineer is called upon in the design of the connecting details between members and their supports for the greatest judgment and design skill. All designed structure loads must be transmitted through successive connections from points of application down to the footings. For each succeeding components of structure must carry the accumulated dead weight of tributary components, and in preliminary design studies these weights can only be roughly estimated. The elimination of bending or eccentricity in local elements is important. As one example, i f a column is carried on top of a beam, the webs of the column and beam should be in alignment; but since the major load in the column is carried in the flanges, the flanges should in turn be supported by bearing stiffeners that are directly beneath. Thus the load is transmitted from point throughout the structure in the most efficient manner without possibility of local failure. Marks for erection and c onnection special marks Steel m arks are used for member identif ication and erection verification. But m ar ks also bring some problems for jobsite operation because fabricators and erectors are us ing self mark system s to defer the steel and parts. On beams the mark should be located on the top flange at the north or east (righthand) end. On columns the mark should be located on the lower end of the shaft on the flange facing north or east. On vertical bracings the mark should be located at the
22 lower end. The f abricator indicate s where an erection mark is to be painted on a detail ed drawing. T he work mark contained in a rectangle shall be shown on each detail with an arrow pointing to the position required. Although workers pay attention to steel marks, many mistakes have been attributable due to appearance problems of the marks or other uncertain things. I n this research, the author focuses on steel RFID identification system to resolve those problems and improve the jobsite management. (see Appendix C) S teel S tructure S upply C hain Because the manufacture of structural steel is a complex and larger project, the planning of steel structure construction always becomes a big challenge for contractors. The step by step procedures and documents that are normally as follows: Step 1: Bidding The a rchitect and engineer provide contract documents: specifications architectural drawing, structural drawings; The fabricator determines the amount of material required, including shapes, sizes, lengths, and work to be done. The fabricator determines the cost for the project and submits a bid. Step 2: Post award stage The fabricator who is awarded a contract is provided with architectural and engineering drawings that are approved for construction. The fabricator develops a material list itemizing the steel requirement for a particular job. The list is arranged in to similar structural shapes and plates to order material from the mills in the most efficient manner. T he fabricator also considers possible extra costs which may be based on: shape, length, quantity, and grade of steel. Development of connection details (a) The fabricators engineering department isolates all connections that are not standard connections or are not fully detailed on the structural engineer s drawings. (b) The fabricator s engineer sizes connection material, for nonstandard connections, in accordance with the loads shown on the structural drawings. T his includes general configuration, size of plate and angles, number and size of bolts, and length and location of
23 welds. (c) Connection details are submitted to the structural engineer for approval before shop detailing has substantially started. Preparation of the shop drawings (a) The fabricator s detailer draws a drawing for each piece of steel to be fabricated showing the specific work to be performed. T he drawing show s general configuration, hole s locations, plates, connection angles, bolts, copes, weld sizes, and so on. (b) The fabricator checks shop details, particularly for general fit and dimensions. Step 3: Architect s and/or structural engineer s approval The fabricator submits shop drawings to the str uctural engineer for approval. Shop drawings are reviewed for: (a) Correct interpretation of structural drawings (b) Correct size of supporting members (c) Correct number of bolts in connections (Shop and F ield) (d) Correct amount of weld The Structural engineer returns shop drawings to the fabricator with comments and status, as follows. (a) Approved as submittedproceed (b) Approved subject to comments proceed (c) Rejected corrections must be made and shop drawings resubmitted. Step 4: Erection plans The AISC c ertified e rector is required to prepare a Project Specific Erection Plan" These plans are often prepared by the erector's engineer, including what cranes will be used to pick up what pieces, where to start, how to plumb the building, when the bolts have to be tightened befo re you can add more steel to the structure, etc. If the job is complicated, perhaps a structural engineer who understands steel erection should be employed to prepare the plan including:
24 Description shows the steel erection where each piece is to be installed and the field welding required. Erection plans are developed simultaneously with the shop details. The location and the number of the piece are immediately recorded on the erection plan. The erection plans are submitted to the structural engineer in various forms of completion. It is the only document that correlates shop drawings to field location (and consequently, the location shown on structural drawings). Mill Fabrication Structural steel shapes are manufactured at rolling mills and shipped to st eel fabricating plants where the pieces are prepared for a particular building project. The fabricating process is fairly complex and requires a number of exacting procedures. The fabricator of structure steel must first, based on the structur al drawings, order the appropriate shapes in the necessary lengths from the steel mill. The fabricator must then prepare detailed drawings showing exact lengths to be cut, holes to be drilled or punched, items to be welded, and so on, so that the fabrication shop can p repare the pieces properly before they shipped to the job site. The details of every piece must be shown and dimensioned accurately at shop drawings and are to fit together properly at the job site. These must be prepared in strict accordance with the arch itect s and structure engineer s drawings. Pre Erection with contractor or subcontractor The erection process is usually complex depending on the size and configuration of the building and variety of equipment and techniques that must be employed. Essent ially, during the erection process, the steel members that have been fabricated are placed in their proper position in the building frame. T he erection of the frame may be done by the steel fabricator or subcontracted. There are several issues that must be considered to the proper positioning and securing of the fabricated pieces, such as the manner in which the pieces will be shipped to the building site, the ship route and maximum size of shipping requested whether large piece
25 assembly take place at buil ding site or shop, site conditions must also be considered, the necessary erection equipment needs to be considered from access to move out to job site. It may also be necessary to develop a schedule for the erection process, coordinating with other trades involved in the construction of the building. Consequently, an erection scheme may need to be developed simultaneously with the fabrication process. Erection p lan A steel erection follow s an erection plan, which is prepared by a fabricator. The erection plans are similar to the structural framing plans. It is a two dimensional line drawing showing the framing at each floor, and where the sides of the building involve more than simply columns, a line drawing of the building frame elevation would be includ ed. The erection plans indicated the location of each piece of steel to be placed, and each piece is marked with a letter or number or a combination of both. Sequences of F abrication and E rection The use of welding requires careful and competent inspectio n both with regard to procedure and finished product. Both shop and field inspections of welding are important, as the quality of welds depends to a large extent on the skill, character, and endurance of the welder. Punching of holes, subpunching with reaming or drilling should be employed to company with bolting or riveting connecting. Automatic machines are using at shop to do such jobs to improve the e ffective and deduct the damages of materials. In the case of shop assemblies joining several differen t plates or members, economy may be achieved by clamping the pieces into a single pack for single or multiple drilling through all pieces in one operation. Drilling provides smooth edges of holes and the best possible resistance to repeated load.
26 The arr angement, number, type, and location of field splices and connections should be planned so as to avoid unnecessary duplication of construction equipment and provide the simplest possible erection plan with a minimum of field work. Connections should be arr anged to facilitate field assembly. A detail, wellthought out construction plan will do the most to minimize the total cost of the project. A definite erection plan should be generated, but the contractor should have freedom to exercise their own ingenuit y through alternative schemes that meet the approval of the owner. One cause of failure occurs during the lifting operations of trusses and girders, which are normally in tension, because they may be placed in compression with consequent possible buckling failures. Even after the main frames and members are successfully placed in the structure, failures have occasionally occurred because of the haste with which construction of main framing has proceeded without attention to the walls and roof, after perma nent bracing, roof, and walls are in place, the wind load resistance of the structure will be greatly increased. In the case of very long plate girders used in bridge construction, experienced contractors typically provide special horizontal temporary trus s systems fixed to the plate girders for use only during erection. Although erection is normally the responsibility of the steel contractor, the design engineer can help in complex cases by scheduling the bracing that must be supplied as the construction i s in progress. Alternatively, the contractor may be required to submit erection procedure plans to the engineer for approval. Construction failures are usually caused by lack of space frame stability and many more failures occur during erection than service of the finished structures. The T echnique D eveloped and U s ed in S teel S tructure There are many companies conducting research on creating some software to improve construction management level. Autodesk, VersaCaD, Summagraphics, Microstation and other
27 co mpanies developing CAD has changed the tradition of architecture design methods so that designer can get rid of physical ruler and paper. Adobe 3D MAX gave the first 3D simulation picture of project. According to Eastman (1999), computer aided design is d ependent on three different types of technologies: display technology, processor capability and software capabilities. Beginning in the mid 1950s, computer applications were written to automatically calculate engineering formulas that had previously been c alculated manually. Later, CAD companies developed and used several other display technologies, including storage tubes (principally sold by Tektronix) and plasma displays. In the late 1970s, pixel based bitmap displays became available and within a few years grew to dominate the display market. Up to the middle 1980s, CAD systems were developed for mini computers or time shared mainframes. After 1990s, internet and IT technique development bring CAD to a fantastic level. PC solids modeling and Virtual Rea lity make construction industry a virtually and paperless world. Currently, there are quite a few trends in Information Technology (IT) construction research and modeling design that affect the construction industry. Examples include construction software for design and development purpose, such as professional specification software or construction scheduling and estimating software. Other examples include Web base construction project management software, s imulation by using computer visualization models and Building Information Modeling (BIM). These software products are updated frequently. Intense competition pushes the producers to improve their designs and make their software more functional and user friendly.
28 Web based Project Management The Interne t provides a platform for webbased construction project management models. Figure 21 shows an example of using a webbased project management service in the coordination of construction processes. Such services include webbased project management provi ded by e builder ; BuildIT provided by BuildIT systems; @task (http://www.attask.com ) ; and ProjectDox provided by Avolve Software. (http://www.projectdox.com ). Web based visualization is an advanced system that uses HTML or other means to transfer computer graphics and 3D visualized information. The computer graphics and 3D visualized information are transferred to web based databases. (s ee Figure 2 1) Figure 21. Web base Project Management (by Avolve Software) Visualization and VRML VRML is an acronym for the Virtual Reality Modeling Language. Using VRML 3D virtual worlds can be developed. The most exciting feature of VRML is that it enables users to create dynamic worlds and sensory rich virtual environments on the Internet, including the ability to: (1) a nimate objects in real worlds; (2) mak e real worlds; (3) play sounds and movies within users worlds; (4) allow users to int eract with their own worlds; and (5) control and
29 enhance worlds with scripts that users create to act on their own VRML worlds Figure 2 2 explains the structure of virtual reality system. Picture 1 Picture 2 Picture 3 Picture... Practice Zone VR World Real World Operation 1 Operation 2 Operation 3 Operation .. Workshop Figure 22. V irtual Reality a rchitecture The first version of VRML was specified in November 1994 (Berners Lee 1994). This version was specified from, and very closely resembled, the Application Program Interface ( API ) and file format of the Open Inventor software component. The current and functionally complete version is VRML97 (ISO/IEC 147721:1997). VRML has now been superseded by X3D (ISO/IEC 197751). The major function of VRML is to create a virtual reality environment. Its compatibility with other software products is poor. Another drawback of VRML is its difficulty to represent space on the normal computer screen instead of virtual environment around users. The advantage of VRML and its successor, X3D is that they have been accepted as international standards by the International Organization for Standardization (ISO) (Ames 1997). Building Information Modeling (BIM) BIM is a set of information generated and maintained throughout the life cycle of a building. It is based on a view that the term Building Information Modeling is basically the
30 same as Building Product Model, which Eastman (2008) has used extensively in his book and papers since the late 1970s. (Product model means data model or information model in engineering.) Conceptually, BIM models are object based parametric models wi th a predefined set of object families, each having behaviors programmed within them. These new capabilities allow organizations to define object families in their own way and to support their own methods of detailing and layout. BIM are characterized by building components Those components include data that describe how they behave For example, the behavior data include their taken off, their specification s, and their energy analysis The energy analysis feature of the BIM models give them great potenti al for the implementation of building energy efficiency analysis, green material selection, and building sustainability analysis. The behavior data are consistent and nonredundant data such that changes to component data are represented in all views of th e component C oordinated data such as that all views from a model are represented in a coordinated way (Eastman 2008) BIM is the process of generating and managing building data during its life cycle. Typically it uses threedimensional, real time, dynami c building modeling software to increase productivity in building design and construction. BIM encompasses building geometry, spatial relationships, geographic information, and quantities and properties of building components (for example manufacturers' de tails). BIM can be used to document the entire building life cycle including the processes of construction and facility operation. Quantities and shared properties of materials can easily be
31 extracted. Scopes of work can be isolated and defined. Systems, assemblies, and sequences can be shown in a relative scale with the entire facility or group of facilities (Eastman 2008) Figure 23 and Table 21 show the difference between the traditional project documents and a building information model. (Leicht 2007) In the traditional project documents, plans are two dimensional, including plan view, section view, and elevation view. In building information models, a construction project can be viewed from any direction, in 3dimensional format, and in any customer defined scale. The HVAC system in the traditional documents is either in two dimensional plan view or isometric view. The HVAC system in the building information models will be in 3dimensional format and the building information models can demonstrate t he quantities of the fixtures and any other quantities the user wants to know. The building information models also have the capacity to do energy analysis. The energy analysis function of building information models makes the coordination, optimization, a nd energy efficiency of the electrical, mechanical, and plumbing systems of buildings into reality. BIM is able to achieve such improvements by modeling representations of the actual parts and pieces being used to build a building. This is a substantial s hift from the traditional computer aided drafting method of drawing with vector file based lines that combine to represent objects. Architectural design services mainly consist of five phases. They are schematic design; design development; construction do cuments; bidding and negotiation and construction administration phase (AIA B141). BIMs benefits span all phases of design. Eastman (2008) listed four viewpoints to design process, which is conceptual design, the use of BIM for design and analysis of buil ding systems, its use in developing construction information, and design and construction integration.
32 Figure 23. The f unction differences between BIM and tradition al documents (Leicht 2007) BIM is a combination of all the project data, d isplayed in a designed systematic model. Its functions include collection, analysis, judgment, and operation. Most building models are based on informationrich database systems.(see Figure 2 3) They are a result of a combination of project design models, such as CAD (2D to 3D), with other AEC (Architect/Engineer/Contractor) information models. BIM has improved itself from a simple storage, sharing and exchange model to a multifunctional full fledge work process and control center ( http://usa.autodesk.com )
33 Table 21. Comparing BIM and t raditional documentation (Leicht and Messner 2007) Current BIM software still has some drawbacks that need to be improved. One drawback is that BIM has little compatibili ty. There is no universally accepted standard yet. Even though CIS/2 is the first standard approved by American Institute of Steel Construction (AISC), it only applies to the product model and electronic data exchange file format for structural steel proje ct information. The National Institute of Building Science (NIBS) developed the National Standard for Building Information Modeling (NBIMS). Most software products are proprietary, e.g. VBE (Virtual Building Environment), Virtual Building, Building SMART, AUTOCAD, VDC (Virtual Design and Construction), and Integrated Practice, etc. Each developer has their design preferences and holds on to their copyrights tightly. Another major drawback of BIM is in its data management ability. BIM was designed for compa nies that use individual safe server and databases. The ability of using open data sources Traditional Documentation Building Information Model Information Form taken How it was Obtained Form taken How it was obtained Design Concepts Floor Plans 2D Pri nted Sheets 2D & 3D Visualized in BIM Elevations 2D Printed Sheets 2D & 3D Visualized in BIM Sections 2D Printed Sheets 2D & 3D Visualized in BIM Rendering 2D Printed Sheets 2D Visualized in BIM System info Architectural (Room Information) Drawing s & Text Finished Schedule in Drawing & Specifications 3D Images, Text Seen in model, properties window, or generated finish schedule Mechanical (Duct&Equipment) Drawings & Text Found in Drawings & Preliminary Specifications 3D Images, Text Seen in model properties window Major Material/Finishes Drawings & Text Found in Drawings & Preliminary Specifications Visualized in model or plan Properties Window or generated finished schedule System Coordination Not clearly evident Conflicts in Model Conflict report, seen in model Other Description of Work Text Preliminary Specifications Not Included Summary Room Areas Not Included Hand Take offs & Manual Calculations Schedule in model Generated LEED information Text Achievable Points Listed in Specifi cation Not Included Construct ability Drawings & Text Determine from review of documents Model, Plans Determine from review of model
34 and data management in BIM is limited. In case of 3D based BIM object information system (see Figure 2 4), BIM can be developed from a 3D model into a 4D model (3D m odel with schedule control). The 3D graphical model and the schedule of a project file are both information rich, there are possibilities that some mistakes or conflict s may occur in both hardware and software. For example, lack of enough memory, program c rashes, or software bugs. Figure 24. 4D Model created by BIM The interoperability requirements relate to the inter connection feature of the construction documents These documents include drawings, procurement details, sub mittals, specifications etc. They affect building quality. It is anticipated by proponents that BIM can be utilized to bridge the information loss associated with handing a project from design team, to construction team and to building owner/operator Th is bridging is done by allowing each group to add to and refer back to all information they acquire during their period of contribution to the BIM model. For example, a building owner may find evidence of a leak in their building. Rather than blindly exploring the entire physical building, he/she may turn to his/her BIM and see that a water valve is located in the suspect location. The model could also provide the specific valve size, manufacturer, part number, and any other relevant information. Project Scheduling File (Mic rosoft Project or Prima vera) BIM 3D File (AutoCAD 3D, Revit, NavisWorks, CIS/2) BIM 4D Model (NavisWorks, Vico)
35 There have been attempts to creat e BIM for older, pre existing facilities. The se efforts are generally refer r e d according to their key metrics, such as the Facility Condition Index, or FCI. The validity of these models will need to be monitored over time, because t rying to model a building already constructed requires numerous assumptions about design standards, building codes, construction methods, materials, etc. T herefore it is far more complex than building a BIM at the time of the initial design. The American Institute of Architects (AIA) has further defined BIM as "a model based technology linked with a database of project information", and this reflects the general reliance on database technology as the foundation. In the future, structured text documents such as specifications may be able to be searched and linked to regional, national, and international standards of BIM (Leicht 2007) Manufacturing Systems Integration (MSI) System integration was confined to the technical aspects of hardware and the interconnectivity of computing components. Integration had a mechanical connotation and piecemeal quality: making different pieces of equipment work together (Wyzalek 2000) In the past, systems integration was confined to a technical, operations task part of the w ider area of systems engineering. Today, systems integration is a strategic task, which pervades business management not only at the engineering level but also in senior management decisionmaking (Prencipe 2004). The process of steel fabrication has three major steps : design > m anufacturing > delivery A ll of these are complex industrial detailed work. Steel design is comprised of architectural drawing, engineering design, and shop detail drawing. Manufacturing is comprised of steel purchasing, transfer ring, cutting, drilling, welding, and storing. Delivery is comprised of truck arrangement, crane arrangement, and sequence arrangement. Every part of these sequences
36 requires unique equipment and follows different operation rules. Some major steel fabricat ion companies own lots of hi tech machines, such as digital beds or computer controlled machines. Manufacturing System Integration is a very useful system for most manufacturing operations. It is also beneficial for fabricators after making adaptations and improvements. The goal of MSI is to bring together the component subsystems into one system and ensuring that the subsystems function together as a unified system. In information technology, systems integration is the process of linking together different computing systems and software applications physically or functionally. The system integrator brings together discrete systems utilizing a variety of techniques such as computer networking, enterprise application integration, business process management or manual programming. (http://www.mel.nist.gov) A system is an aggregation of subsystems cooperating so that the system is able to deliver the over arching functionality. System integration involves integrating existing (often disparate) subsystems. The su bsystems will have interfaces. Integration involves joining the subsystems together by gluing their interfaces together. If the interfaces do not directly interlock, the glue between them can provide the required mappings. System integration is about determining the required glue. (http://www.sharpy.dircon.co.uk/index.htm). System integration is also about value adding to the system, capabilities that are possible because of interactions between subsystems. The construction industry needs to better in tegrate the activities in the subsystems. The subsystems include design, fabrication, construction and operation of constructed facilities through the use of computer technology (Wilson and Bryan 1994). Integration of systems has become a topic of interest to many professionals, including those in the AEC industry. From an information systems perspective, integration can be defined as the design and development of
37 information systems that combine several hardware and/or software components to cooperate and carry out a joint task that would be beyond the capabilities of any one of them individually. System integration in the AEC industry can be applied at three levels: Interapplication integration. This involves combining the computer applications of one company into one integrated system. These applications can then share data and call each others procedures. Intersystem integration. This exists when one companys applications integrate with those used by other project participants. Industry wide inte gration. This will allow any project participant to communicate electronically with any segment of the industry (e.g., owners, designers, suppliers, financiers, regulators, etc.). It would also ensure consistency across different projects. A more widely used term in the construction industry to represent integration is Computer Integrated Construction (CIC) (Karttam and Levitt 1990). CIC can be defined as a business process that links the project participants in a facility project into a collaborative team through all phases of a project. Figure 25 shows an overall CIC framework. The framework includes both computer aided drawing/design (CADD), and visual computing and computer aided engineering (CAE) (Xie 2005). MSI is used to bring together the component subsystems into one system and ensuring that the subsystems function together as a system. In information technology, systems integration is the process of linking together different computing systems and software applications physically or functionally. The system integrator brings together discrete systems utilizing a variety of techniques such as computer networking, enterprise application integration, business proces s m anagement or manual programming. In this research, MSI will bring the Webbased 3/4D BIM
38 Visualization Model together and test it to make sure the functions are properly developed by proposed model. Schematic Design Design Development Detail Design & Specifications Facility Management Systems (Operate & Maintain) Cost, Schedule, Material & Quality Mgt. Systems Cost and Schedule Estimation System CAD/CAE Framework Product Model of 3D CAD Objects in OODBMS, Data Mgt. System, LAN/WAN Communication Automated Construction & Link to Sub CAD/CAM Construction Planning Figure 25. Computer i ntegrated c onstruction t echnology f ramework (Xie 2005) BIM on Site The functions involved in the use of BIM onsite are verification, guidance, and t racking of c onstruction a ctivities. Contractors must field verify the installation of building components to ensure that dimension s are correct and performance specifications are met. Even when a project team creates an accurate model, human error during installation remains a possibility, and catching these errors as they occur or as soon as possible has great value (Eastman 2008) Eastman noted that the intimate knowledge gained by virtually building the project allowed t he team to discover field errors. The team combined traditional field verification processes of daily site walks with model reviews to detect potential field errors. More sophisticated techniques are evolving to support field verification, guide layout, and track installation. Some examples are as follows : Laser scanning technologies : Contractors can use laser scanning technologies, such as laser measurement devices that report data directly to a BIM tool, to verify that concrete pours
39 are situated in exactly the correct location or that columns are rehabilitation work s and capturing asbuilt construction details (GSA 2007). Machine guidance technologies : Earthwork contractors can use machine guided equipment to guide and verify grading and excavation activ ities driven by dimensions extracted from a 3D/BIM model. GPS technologies : Rapid advances in Geographical Position System ( GPS ) and the availability of mobile GPS devices offer contractors the ability to link the building model to global positioningsystems to verify locations. RFID tags. Radio Frequency Identification (RFID) tags can support the tracking of component delivery and installation onsite. BIM components that include references to RFID tags can automatically update building product data and construction process data with links to field scanning devices. BIM combined with RFID can provide contractors with rapid feedback on field progress and installation (Eastman 2008) More detailed discussion of RFID will be presented in the next section. The use of BIM in the field will increase dramatically as mobile devices and methods to deliver BIM information to field workers becomes commonplace. A survey (Eastman 2008) conducted in early 2007 found that 74% of US architectural firms are already using 3D modeling and BIM tools, although only 34% of those use it for intelligent modeling. BIM and 4D CAD tools are becoming common in construction site offices (Eastman 2008). BIM will contribute to a high degree of fewer documents, far fewer errors, less waste, and higher productivity, better analyses and exploration of more alternatives, fewer claims, and fewer budget and schedule overruns.
40 But jobsite uncertainty is the big challenge for project managers. Even in a BIM developed by a skillful technique team, one man made mistake may destroy the successful modeling of techniques. The imperfections of the jobsite may include: missing parts, equipment damages, wrong directions, safety violations, bad operations, invisibly recognition, etc. None of them can be reco vered by BIM. In these types of situations on the jobsite, an Identification Coding system is a necessity. Steel Identification with RFID Automatic Identification and Data Capture (AIDC) refers to the methodology of automatically identifying objects, coll ecting data about them, and entering that data directly into computer systems (i.e. without human involvement). Radio Frequency Identification (RFID) is one of the most popular AIDC used in transportation, security, retail, manufacturing and material deliv ery system. It has been used in many areas of the construction material supply chain, but it has not yet been used in the steel supply chain area. The following discussion w ould verify the feasibility and effectiveness of using RFID (Waldner 2008) RFID is an automatic identification method, relying on storing and remotely retrieving data using devices called RFID tags or transponders. The technology requires some extent of cooperation between an RFID reader and an RFID tag. (http://www.aimglobal.org) An RF ID tag is an object that can be applied to or incorporated into a product, animal, or person for the purpose of identification and tracking using radio waves. Some tags can be read from several meters away and beyond the line of sight of the reader. That became one of the major advantages of RFID over bar code. For most bar code implementation, they need to have human involvement in holding a scanner and scan bar codes one by one. Most RFID tags contain at least two parts. One is an integrated circuit for storing and processing information, modulating and demodulating a radio frequency (RF) signal, and other
41 spe cialized functions. The second is an antenna for receiving and transmitting the signal. In the future chipless RFID will allow for discrete identification of tags without an integrated circuit, thereby allowing tags to be printed directly onto assets at a lower cost than traditional tags. (http://www.rfidjournal.com) RFID means the RFID tag in a smart label. It is a new high tech technology used in retail and other industries. It comprises the chip and aluminum, copper or silver antenna bonded to a polyethylene terephthalate (PET) layer that is delivered to the label maker "dry" (without adhesive) or "wet" (attached to a pressure sensitive liner). The inlay is adhered to the back side of the label and printed and encoded in an RFID printer (http://www.pcma g.com) RFID involves the aluminum and copper antennas. But that may cause a problem especially for steel structural items, because metal items and liquids in a carton "detune" the tags and impede backscattering. One way to solve that problem is to use a s mart label contain ing the RFID tag as well as printed bar codes and alphanumeric characters. The printed material can provide redundant UPC and EPC data that can be picked up by a bar code scanner or read by a warehouse employee if the RFID tag cannot be r ead. RFID smart labels are printed and encoded at the same time in an RFID printer. ERA ( European Research Area) in its report discussed the implementation of RFID with the focus on logistics and supply chain management. RFID in construction offers a new method for industrial innovation and efficiency improvements, but there are still some considerable obstacles: (ERA 2006) Immature application of advanced logistic systems and the absence of information and identification systems in the construction indus try; Lack of awareness of RFID's potential in the construction industry; Low RFID knowledge and awareness in the construction sector;
42 Lack of robust RFID initiatives in the construction industry; Lack of successful RFID implementation cases that thoroughly show its potentials; The traditionally construction industry and its relatively negative attitudes are towards new innovations and technology. RFID technology has a data memory function. It has been used in the passport and identification (ID) checking sy stem since 2006 in UK. The microchip in the passport can store personal information like the passport number, the holder's date of birth, the passport expiry date, etc. Even the biometric image can be contained on the printed page of the passport on a "mac hine readable zone (Guardian 2006). It is possible to have more information stored in RFID tags or chips in the future and to track information by simply using a reader without a platform of RFID database from computer system. Table 22. RFID performance a dvantages and d isadvantages RFID Performance Descript Advantage Disadvantage Technique Maturate technique after twenty more years developing Passive Wave Range limitation of about 20 foot. Accurate Good enough for building jobsite work. More exactitud e more cost. The reader cost plus PDA cost usually thousands dollar. Standard You have option to choice the one you like among hundreds productions. No universal standard and universal ports when change tag or reader from different factory. Cost Tag cos t decrease after technique improved. The cheapest around 20 60 Cents and recycle able. Reader and station price high. Implementation Widely using at retail, auto industry for supply chain. Inconvenience for multi transaction task when transfer data from different user because of confliction of software or missing connection ports. Table 23 shows the use of RFID in the different systems. In this table, the advantages and disadvantages of using RFID in these software systems are discussed. Most of them are BIM tools. After using RFID, the noticeable help is the improvement to their components identification and tracking functions. This is very important to digital transaction and data collection.
43 Table 2-3. RFID specification and concepts (http://data-acquisition.globalspec.com 2008) RFID Specification Type Tag / Transponder A microchip attached to an antenna that picks up signals from and sends signals to a reader. The tag contains a unique serial number, but may have other information, such as a customer' account number. RFID tags can be active tags, passive tags and semi-p assive tags. RFID tags are sometimes referred to as transponders. Reader The reader communicates with the RFID tag via radio waves and passes the information in digital form to a computer system. Antenna The antenna is the conductive elem ent that enables the tag to send and receive data. Passive tags usually have a coiled antenna that couples with the coiled antenna of the reader to form a magnetic field. The tag draws power from this field. Transceiver Transceivers both receive and transmit data. Printer / Encoder RFID are used to encode RFID tags. System A system includes both a reader and tags. A system can also include a printer / encoder. Technology Passive An RFID tag without a battery. When radio waves from the reader reach th e chips antenna, it creates a magnetic field. The tag draws power from the field and is able to send back information stored on the chip. Semi-passive Similar to active tags, but the battery is used to run the microchip's circuitry but not to communicate with the reader. Some semi-passive tags sleep until they are woken up by a signal from the reader, which conserves battery life. Active An RFID tag that comes with a battery that is us ed to power the microchips circuitry and transmit a signal to a reader. Active tags can be read from 100 feet or more away. Interface RS232 Interface between data terminal equipment and data communicatio ns equipment employing serial binary data interchange. RS422 RS422 is a balanced serial interface for the transm ission of digital data. It was designed for greater distances and higher Baud rates than RS232. RS485 RS485 is a balanced serial interface for the tr ansmission of digital data. The advantage of a balanced signal is the greater immunity to nois e. The difference between RS422 and RS485 is that RS485 can be transformed into a multi-point application. IC Inter-Integrated Circuit (IC) is a bus is an inexpe nsive type of chip interconnection that is popular on circuit boards (pronounced "Eye Squared C"). TTL Transistor-transistor logic (TTL) is a common type of digital circuit in which the output is derived from two transistors. More commonl y, however, TTL is used to designate any type of digital input or device. USB USB products (Universal Serial Bus) is the original standard that supports data transfer rates of up to 12 Mbps. Performance Frequency RFID products use low, high, ultra-high and microwave frequencies. Each frequency has advantages and disadvantages that make them more suitable for some applications than for others. Memory The amount of memory controls the am ount of data that can be stored on a tag. Read Rate The maximum rate at whic h data can be read from a tag expre ssed in bits or bytes per second. Detection Range The distance from which a reader can communicate w ith a tag. Active tags have a longer read range than passive tags because they use a battery to transmit signals to the reader. With passive tags, the read range is influenced by frequency, reader output power, antenna design, and method of powering up the tag. Operating Temperature The range of temperatures through whic h the RFID product is designed to operate. Features Portable The RFID reader is not a fixed system. Read / Write RFID tags that can st ore new information on its microchip. Anti-collision / Multiread A general term used to cover methods of preven ting radio waves from one device from interfering with radio waves from another. Anti-collision algorithms are also used to read more than one tag in the same reader's field. Non-contact Reader can operate without ph ysical contact with the tag being read. Encryption A system that scrambles its da ta to prevent unauthorized duplication. Continuous Reporting A mode of reader operation where a transponder ID is reported continuously while that transponder remains in the field of the reader.
44 When selecting RFID tr ansponder integrated circuits, the primary selection criteria are memory size, transaction speed, communication range and cost (Dressen 2008). CryptoRF is the world's first 13.56 MHz RFID devices with a 64bit embedded cryptographic engine, dual authentic ation capability, and up to 64 Kbytes of memory each with up to 16 individually configurable sectors (http://www.atmel.com 2009). It is possible to integrate RFID technology with AUTOCAD, TEKLA, DESIGN DATA, VELA SYSTEMS and other systems in USA in steel frame building design in construction companies. The RFID real time location system is a newly developed technology. ITEC Corporation is a leading Electronics Manufacturing Service (EMS) provider for the RFID and wireless communications industry. It provides an overview of its I'm Here active RFID real time location system (RTLS), which the firm has deployed within its own manufacturing facility in Nagano, Japan. Another way to solve bac kscattering problem is to use active RFID. As a forefront wireless technology, active RFID is still not effectively integrated in many cases, but it will give big benefits to the construction industry tomorrow. ITECs Active RFID Model Factory 1.0 solutio n is based on technology jointly developed with its U.S. business partner, RF Code, and utilizes RFID tags placed on critical assets and RF readers placed in key locations to monitor manufacturing processes and staff activity. RF Code is a leading provider of r eal t ime RFID a sset t racking solutions in the U.S. (http://www.itec america.com) A ctive RFID technology has wide implementation in the construction industry. Active RFID technology supports the visibility of high value assets, such as trailers, excava tors, forklifts, light towers and other construction equipment. For example, it can pinpoint the location of heavy equipment for monitoring and control. It can facilitat e emergency evacuation of
45 hazardous sites, asset tracking and access control Active R FID can automate order fulfillment in leasing operations, for better asset availability condition, greater receipt/billing accuracy and higher customer satisfaction. Active RFID can also locate personnel in real time and control access to restricted areas and equipment for increased personnel safety and equipment security. With its long read ranges and ability to perform in harsh, wet and metallic environment, active RFID technology can be implemented to the following construction situations (http://www.wav etrend.net/industries_const.aspx) : Automated construction equipment leasing/plant hire Inventory control and stock distribution Access control to sensitive areas/equipment Emergency personnel recall and evacuation Time and attendance management Out of hours security at construction sites Overcoming these barriers depends on the development of an integrated approach between technical organization, training programmers, competences and management (ERA 2006). The advantages and disadvantages of RFID are li sted in Table 2 2. Many research projects have shown the potential of RFID application in various areas of the construction industry, such as concrete operations, labor management, productivity analysis, construction tool tracking, and pipe spool tracking. Some trials have shown that RFID in the structur al steel work enabled more accurate logistics and progress management, and that this could lead to the reduction of risks, including material loss and schedule overrun, by monitoring the erection process on a steel member unit basis. RFID combined with 4D PMS (RFID+4D PMS) offered more efficiency in process time and in stockyard duration than the existing process, and thus saved time and money (Chin 2008).
46 Web based computer software facilitates long distanc e communication between the offices of the AEC team members. BIM would be the very convenient tool for the AEC industry in providing a paperless and information rich reference to track the progress of a real project. The use of RFID+4D adds more elaborate data and visualization detail to the project. This research is going to look at the advantage s and disadvantage s of each methods and how to combine their functionality synergistically to assist in the fabrication and erection of structural steel components The use of BIM and the above described synergistically functionality systems facilitate the selection of the optimization plan and help manager make the right decision. In the proposed system, the framework design will focus on the steel structure fabrication and erection. Steel construction can be divided into four continual processes: Structural Design, Detailing and Estimating, Fabrication, and Erection (installation). (www.aisc.org) The process of structural steel installation generally includes: base plate and base concrete setting, column erection, beam erection, bracing, joist and truss installation. Planning and scheduling may be complicated if a project has lots of steel items to install. Two methods can be used to show a project schedule. One m ethod is to use different colors to distinguish the different parts, such as columns, beams, bracings, or trusses. Special colors can also be used to mark the finished jobs and goingto finish jobs. For example, use green for all columns not installed and yellow for the installed columns; for beams, use red for the uninstalled and orange for the installed. Other pieces such as plates, angles, channels, and tubes, can also be mark ed by selected colors (see Figure 26 ).
47 Figure 26. VRML model with several display features (Lipman and Reed 2003) Another method is to use serial numbers to distinguish steel parts which have RFID tags. A handheld scanner may be introduced into the proposed model depending on the specialty of the steel erection sequenc e. It will be configurable with different computer systems and scheduling software. When using RFID, from the first piece steel of the project to the last one installed, all users involved can track it the first time. By checking the data from the scanner, users can find out whether a job has already been done or is still ongoing. So a project supervisor can use it to check the daily project progress and organize activities to follow the schedule. Users can also find all related information for each part as well. For example, Code# 125013 means: Column#3, W12x120, two holes need to be drilled for safety belts on each floor, 6 bolts connection with two W12x404 cut flanges, one L3x3x1/2 on second floor, one W12x264 cut flange and L 3x3x1/4 on third floor, one moment connection with W10x65 on second floor, and so on. Figure 2 6 is an example for a VR model showing the information of different pieces of steel.
48 On the left side of the image in Figure 26 are buttons to change the rendering mode and switches to turn on and off the views of bolts, holes, welds, labels, axes, and sequences. The steel members are displayed in a transparent mode with a wire frame outline. In this mode, the blue clip angles are visible through the yellow column. In the bottom left is a gray gusset plate with six holes. Each of the parts has a text label consisting of its piece name, size and section type. The label floats above the part and always faces the viewer. On the right, a text popup appears when clicking on any part in the model. The popup contains information about all of the parts in an assembly. The first line indicates which sequence the assembly is part of. A sequence is any group of assemblies. The second line is the mark of the assembly. The first table contains infor mation about all of the parts in the assembly. The columns of the table are: quantity, piece mark, section type, material grade, and length or thickness. The second table contains information about the bolts used in the assembly. The columns of the bolts t able are: quantity, bolt diameter, material grade, and quantity and type of washer (Lipman and Reed 2003). The key to implementing this model is using RFID (Radiofrequency identification) techniques. This research suggests that RFID tags should be used a fter the first step of fabrication when the major structur al steel are cut and other minor components(i.e. plates, angles, trusses) are made. The RFID technique should also be used for the steel structure erection. The scanner is used to scan each piece of the steel structure with a RFID barcode, at least for main column and beams. After the job is done, each piece of information scanned will be translated into a code that represents the steel. Then the data will be imported to the information system and change the color of steel in 4D VR model system. This serial code system is different from the bar code system, which is used in fabrication and erection by some companies. The serial code system is not just a tracking code; it is part of the proposed real t ime
49 4D VR system. It has a broader site management perspective, aiming to deal with not only dayto day but also item to item activities. This method can be used for all steel parts, even for plates and bolts. The code can be developed by adopting an exist ing bar code system or by creating a new standard to reflect the workflow or the supply chain. Today, RFID is used in enterprise supply chain management to improve the efficiency of inventory tracking and management. However, growth and adoption in the enterprise supply chain market is limited because current commercial technology does not link the indoor tracking to the overall endto end supply chain visibility. The workflow used in deploying RFID is shown in Figure 27 A manufacturer puts a code on a piece of steel then sends it to a fabricator. The fabricator reads it at same time through BIM and then works on the shop drawings when waiting for the material to arrive. The storage area will reserve a place to save it. The scheduler can adjust the schedu le. The jobsite manager will be informed about the parts fabricated soon. Other involved workers can see the related details of the piece of steel at real time. After the fabricators job is done, the piece of steel will be sent to jobsite according to the shipping schedule, everybody will know that the part was shipped out and they can plan for it. The piece of steel will then be scanned in by a site supervisor. The above system uses a shipping RFID code control schema. The steel erection will follow an er ection and crane schedule. An erector will scan the parts before erection, and will automatically enter the data into the 4D BIM system. The 4D BIM system will show whether a piece of steel has been installed or not by using the color code. When the schedule is changed, it will show in real time on the 4D visualization model.
50 R F I D C O D E Designer and Engineer Fabricator Manufacturer PM and Site Supervisor Erector MEP Subcontractor Inspector Figure 27. RFID c oding s ystem w orkflow When an inspector visits a job site, he/she could first use this 4D virtualization model and by checking the BIM system will know what is goi ng on at site, to see if every sequence follows the inspection requirements. Then he/she could go to jobsite to check the real details. The contractor, architect, or owner can track the results of change orders using this system and make sure the results are acceptable. The advantage of using RFID in this model is that it can provide information to contractors and help them making judgment on uncertain things, such as missing parts, delayed orders, and misused materials. For example, let us assume the av erage time for a beam to be shipped out and be erected on site is one week. If the system indicates that the wrong beam was shipped on site then that means there is a one week buffer to reorder or adjust the work sequence Steel erection needs a precise and safe operation solution. A laser based Robotic Total Station may be used in steel erection depending on the need for 3D mechanical, electrical, and plumbing (MEP) layout function. With the Trimble MEP layout solution, mechanical, electrical,
51 and plumbi ng contractors can increase productivity and simplify the layout of sleeves and hangers. Trimble MEP enables mechanical, electrical and plumbing contractors to take 3D positional data to the field digitally, increasing productivity and accuracy by improving layout processes (http://www.trimble.com 2009). Three basic components of GPS are used on the construction job site: absolute location, relative movement, and time transfer. In construction jobs, GPS is used in setting grading levels, shipment tracking, and site layout, etc. But a normal civilian used GPS system, the accuracy is in the meter error range. This limits the use of GPS used in survey or level grading that requires accuracy. Recently, Topcon has made millimeter accuracy in its new product: Mil limeter GPS. This new tool can limit accuracy in 10 Millimeter which is adequate for most precision and productive uses. Millimeter GPS+ combines the advantages of laser (multi user and high vertical accuracy) with GPS (multiuser and 3D) into one versa tile and easy to use system. This patented technology improves grading accuracy up to 300% over existing 3D GPS machine systems (http://www.topconpositioning.com 2009). Both RFID tags and GPS receivers have been handling the important work of tracking ver y well. GPS is able to transmit the location data. The device then communicates the RFID data via a unique ID and channel to any reader within 200 meters (http://rfidtimes.org 2006). It has been found that the locating abilities of the tag locator of the Millimeter GPS+ are promising and give accurate latitude and longitude measurement. The readings are precise up to 3 to 5 meters. This is bundled in with an active RFID tag that operates on the frequency band of 429 MHz
52 From the above research results, it is evident that RFID tags can help in steel erection by allowing project managers who use them to track progress in a real time 4D BIM model. The 4D BIM model will also contain information about project planning and scheduling, cost analysis, reporting, i nventory management, and erection sequence management. The RFID tags will also facilitate the incorporation of data sharing and transferring into drawing, inventory, and supply chain systems. Differential Global Positioning System (DGPS) is an enhancement to Global Positioning System that uses a network of fixed, groundbased reference stations to broadcast the difference between the positions indicated b y the satellite systems and the known fixed positions. (http://www.trinityhouse.co.uk 2009) The term can refer both to the generalized technique as well as specific implementations using it. It is often used to refer specifically to systems that re broadcast the corrections from groundbased transmitters of shorter range. The Millimeter GPS is one of DGPS type equipment. Its Laser Zone system is comprised of three components: Positioning Zone Laser Transmitter, Positioning Zone Sensor (for Mobile Rover Applications), and a Positioning Zone Sensor (for Machine Control Applications). Position zone laser transmitter sets up and operates much like a standard rotating laser (http://www.topconpositioning.com 2009). CIMSteel Integration Standards (CIS/2) CIMsteel stands for the Computer Integrated Manufacturing of Constructional Steelwork (http://www.cis2.org). The CIMSteel Integration Standards (CIS/2) is the product model and electronic data ex change file format for structural steel project information. CIS/2 is intended to create a seamless and integrated flow of information among all parties of the steel supply chain involved in the construction of steel framed structures. It has been adopted by the American
53 Institute of Steel Construction as their format for data exchange between steel related CAD software. CIS/2 has been implemented as a file import or export by many steel design, analysis, engineering, f abrication, and construction software packages. A CIS/2 file exported by an analysis or design program can be imported into a detailing program to de sign the connections. CIS/2 itself is not a software package with user interface. The user will see it as f ile format CIS/2 data format can be used for import or export functions in steel related CAD software. The CIS/2 standard covers everything, including: nuts bolts columns, girders, and other materials It also includes loads to frames and assemblies. S teel s tructures can be represented as analysis, design, or manufacturing (detailed) models in computer systems. There is a logical relationship between the different types of models. For example, a beam in an analysis model can be further subdivided into s everal sections depending on the load distribution pattern on it. It is logically only one beam in the detailed model. T he calculation result of the load at the end of the beam will be used to design the bolts and the weld. The use of CIS/2 and IFC is an important part of improving the efficiency of the delivery of structural steel projects in the steel supply chain. It can eliminate the redundant and error prone reentry of the information about structural steel items Interoperability between different CAD software packages using CIS/2 and IFC play a critical role in the wide acceptance of BI M. The National Institute for Standards and Testing (NIST) was represented on the American Institute of Steel Construction ( AISC's ) Electronic Data Interchange (EDI) R eview Team The review team chose CIS/2 as the standard for electronic data interchange. NIST has helped software vendors to implement the standard and helped steel designers, detailers, and fabricators use the standard. The CIS/2 to VRML and IFC Translator was also developed by NIST.
54 A CIS/2 file can be translated into a 3D interactive model in the form of a VRML (Virtual Reality Modeling Language) file. The VRML file can be viewed in a web browser with a free VRML plug in. The translator recognizes CIS/2 entities of analysis and detailing (manufacturing). It also models the designs. Users can visualize CIS/2 files and make them available on the Internet. Software developers can verify their CIS/2 export capabilities (AISC 2006). An example software system for structural steel is composed of Express Engine (Express 2006), Express Data Manager (EPM 2006), or STEP Tools (STEP 2006), etc. The Express Engine and data manager and tools help the detailing and design process es of steel structure The current meth od of selecting an assembly viewpoint does not lend itself to many viewpoints. The translator has a lookup table of dimensions for many of the standard section profile designators. But there are some nonstandard designators that are not in the table. If the designator is not in the lookup table or cannot be parsed, the resulting VRML will show a white member with a rectangular cross section. If the assumed units for the cross section dimensions are different than the units for the length then the cross sect ion will be too large or small (CIS/2 2006). The VRML models were generated from CIS/2 files. The models were supplied by most of the software vendors of steel CAD software packages which have implemented CIS/2 export capabilities (Lipman and Reed 2003). From project design to virtualization demo and 4D implementation, the above systems cover almost every aspect of construction jobs. But none of those programs can systematically go through every construction process because of various reasons. For example, CIS/2 has a few features similar to the proposed system, but it does not list 4D as a choice. CIS/2 does not have enough functions to show some parts in detail, such as bolts, plates and welding methods. Most of these problems are the targets of 3D VR mod els. 4D visualization can help with planning and
55 scheduling. But no software or program of 4D visualization focuses on structural steel fabrication and erection. General Decision Making Model Description For a decisionmaking model, it involves four stage s in the development of the model: model framework design, model developing, model testing, and model implement. In this sequence, the first step need to do is to develop the structure of the application system and decide on what program that going to use to make the model from theory into reality. The construction jobsite has many uncertain conditions and risks. For example, site condition change (ground sink, flooding, weather change); schedule delay (caused by Fabricator, Equipment, or MEP); labor absence; local or OSHA penalty; fabrication mistake; heavy equipment loss by theft; material missing; budget cuts; unexpected damage; and so on. It is difficult to claim a result proposed by the system is the best one or most suitable to the project conditio ns. But it is possible and feasible for the system to generate a result which will satisfy the complicated criteria of the evaluation module of the system. The suggested result would have great potential or possibility to save construction time, decrease c ost, improve safety record, or achieve better quality in the end of the construction process. In the steel structure erection process, there are many factors or variables affecting the job performance. The variables in the process include: time, cost, qual ity, safety procedures, building code, workers experience, etc. Different projects have different weights on the variables. For example, in a time critical project, the time issue will be the most important factor, and hence will have the prevalent weight For a nuclear plant construction project, safety will be the most important one in all the variables. Generally, steel erection is a complex manufacturedelivery installation process with great probability of failures or errors. The time, cost, and safe ty (Building Code and OSHA
56 Regulation) are always the first three considerations of a project. Those three factors can also be used to evaluate a projects performance and quality. Clemen and Reilly show a flowchart to illustrate the decision analysis pro cess. In construction jobsite, we have 5W to help make decision: What, Where, Why, Who, When, this is the way same as to identify the problem. Simplify these processes, a general decision making framework (DMF) for jobsite uncertainty can be use include t he follow steps: (Olbina 2005) Identifying input independent, dependent variables, problems and required Testing the question by experimental, computer simulation and mathematical calculations Obtaining output results Making the decision Most system anal ysis tools and approaches are based on the assumption that the computer system will have a well defined process. But different decision makers approach problem solving in different ways. (Sprague 1982) This is a challenge for system maker to build a fine system for most users but not everyone. BIM decision making model based on systems integration and analysis results, making decision and testing system decisions by different calculation blocks. All those questions that need to be decision can have differ ent results because of personal preferences (see Figure 28 ) For example, project management may needs a result which is good for jobsite performance when subcontractor needs a result for his benefit. In steel structure projects, the erector needs to fini sh his work ASAP but PM needs the project safe and fair for each subcontractor. In this case, the decision makers should have a limitation on rights adoption. P roject M anager should have primary decision right when subcontractors have their decision making rights after PMs decision.
57 Input Testing Output Making Decision Independent Dependent Crane Number Calculations Simulation Experimental Actuual Values of Parameters Required Parameters Compare Make the Decision Required Parameters Actuual Values of Parameters Figure 28. General decision making processes Decision Making Environments and Decision Criteria The decision making process is a problem solving process. It should consider all management related level or positions, such a s accounting, finance, human resource, production and sales, and management functions, such as planning, organizing, leading and controlling. Some decisions can be classified as programmed decision. It can be made by using standard rules or methods. If de cisions rely on judgment and focus on the firms strategic development and survival, it can be classified as nonprogrammer decisions. To deal with most complex decision problems, the rational decision making processes can be use as a simple quantity weight and optimization choice method (Dessler 2001) Traditional, the process of decision making can come from define the program, identify and weight the criteria, develop and analyze the alternative to make a choice and then implement and evaluate the decision. The Information system is a set of persons data, technology, and organizational procedures that work together to retrieve, process, store, and disseminate information to support decision making and control (Dessler 2001) BIM is a cooperation work station for different kinds of information system or programs, its main function is make a easy decision to deal with many resource and different creators.
58 The decision making in BIM can also design as a tradition method that information system application f or each organization level and project position. The BIM Phases of each organization level for a steel structure project can be separated as Design Phase, Manufacture Phase, Transportation Phase and Jobsite Erection Phase. The Decision Support System (DSS ) concept was first articulated in the early 1970s by Michael Scott Morton under the term management decision system (Sprague 1982) BIM decision making model are using different DSS to support it to make the decision for many kinds. In this case, Types of Systems for BIM will be Design Decision System (DDS), Manufacture Decision System (MDS), Supply Decision System (SDD) and Jobsite Decision System (JDS) to compare with those systems in Table 24. The decision situations are variety and depend largely on the decision environment. The two primary decision environments are certainty and uncertainty. In a certainty environment, the best decision will always be associated with the best outcome. The certainty environment is predicated on the fact that the o utcome from each alternative course of action is known. This makes choosing between the alternatives straightforward. But the typical business decision making environment is uncertainty. We may be able to specify the possible outcomes for each alternativ e, but we will be uncertain about which outcome will occur (Groebner 2008). In construction projects, the Building Code, Land and Design requested factor can be including by the certainty environment. Some jobsite uncertainty are listing here: Site condition change; Schedule Delay Fabricator, Equipment, MEP; Labor Absence; OSHA penalty; Fabrication mistaken, like weld a rod plate; Material Missing or Short; Budget cut; Accident
59 Damage. To treat with the se certainty and uncertainty problems always are manage rs big issue especially for those uncertainties. Table 24. Applications of s ystems for e ach o rganizational l evel (Laudon 1998) Applications of S ystems for E ach O rganizational L eve l Strategic Level Systems Sale and Marketing Manufacturing Finance Ac counting Human Resources 5 Year sales trend Forecasting 5 Year Operation Plan Year Budget Forecasting Profit Planning Manpower Planning ManagementLevel Systems Sales Management Inventory Control Budget Control Capital Investment Analysis Relocation Ana lysis Sales Region Analysis Production Scheduling Cost Analysis Pricing/Profitability Analysis Contract Cost Analysis Knowledge Level Systems Engineer Workstations Graphics Workstations Management Workstations Work Processing Document Imaging Elect ronic Calendars Operational Level Systems Order Tracking and Order Processing Machine Control Plant Scheduling and Material Movement Control Securities Trading and Cash Management Payroll, accounts Payables and Accounts Receivable Compensation, Training & Development and Employee Record Keeping To make a decision, you need to establish some basis. The criteria on which the decision is to be made need to be established and perform an analysis of the decision situation and make choice by weighing each de cision option against the criteria. The decision criteria have nonprobabilistic decision criteria and probabilistic decision criteria. The nonprobabilistic criteria do not take into account the probability associated with the outcomes. The criteria of n onprobabilistic decision criteria is aimed at their failure to include important information about the chances of each outcome occurring. Some decision criteria take into account the probabilities associated with each outcome. The certainty environment i s predicated on the fact that the outcome from each alternative course of action is known. This makes choosing between the alternatives straightforward. But the typical business decision making environment is uncertainty. P ossible outcomes could be
60 specifi ed for each alternative, but we will be uncertain about which outcome will occur (Groebner 2008) In construction projects, the Building Code, Land and Design requested factor can be including by the certainty environment. Some jobsite uncertainty are list ing here: Site condition change; Schedule Delay Fabricator, Equipment, MEP; Labor Absence; OSHA penalty; Fabrication mistaken, like weld a rod plate; Material Missing or Short; Budget cut; Accident Damage. To treat with the se certainty and uncertainty prob lems always are managers big issue especially for those uncertainties. To make a decision, you need to establish some basis. The criteria on which the decision is to be made need to be established and perform an analysis of the decision situation and make the choice by weighing each decision option against the criteria. The decision criteria have non probabilistic decision criteria and probabilistic decision criteria. The nonprobabilistic criteria do not take into account the probability associated with the outcomes. The criteria of nonprobabilistic decision criteria is aimed at their failure to include important information about the chances of each outcome occurring. Some decision criteria take into account the probabilities associated with each outco me. This is probabilistic decision criteria. One of there is the expected value criteria (Groebner 2008) The term expected value is often used in statistics to refer to the long run average outcome for a given alternative. Decision Making Generation To make hard decision need data base and model base information sources, dialog generation and user windows. Figure 29 shows an example of the DSS generator for Dialog G eneration and M anagement S ystem (DGMS). It also works for BIM environment .
61 JDS Internal Comput erized Extraction Data Enter/ Capture Data Transfer Exteral Internal Noncomputer ized Data Base D i c t i o n a r y Query R e t r i e v a l Data Files Models Command Language DGMS Users Other Based Modeling and Consulting DSS/MS Group SDS MDS DDS Figure 29. Configuration dialog generation m anagement s ystem of a DSS Generator (Sprague 1982)
62 In this case, types of systems for BIM under the generation system will be Design Decision System (DDS), Manufacture Decision System (MDS), Supply Decision System (SDS) an d Jobsite Decision System (JDS). Design Decision System (DDS) is a decision system to supply the designer. It may use designing system software that company already have or develop a new program model that based on company collected data system. BIM design model tools like Auto CAD, Revit Architecture, Revit MEP are using at BIM DDS. Manufacture Decision System (MDS) is a decision system to help manufacture make decision. The Total Quality Control (TQC) and Computer Numerical Control (CNC) are such systems that current adopting at manufactures. Supply Decision System (SDS) is a decision system for control supply chain There are so much software like Plant Simulation (PS), Enterprise Resource Planning (ERP) and IBM Supply Chain Management (SCM). Jobsite Dec ision System (JDS) is specific system which designed for jobsite decision. Most scheduling software has this function, like Primavera Project Planning. Expedition of Primavera is specific for JDS.
63 CHAPTER 3 METHODOLOGY This study is going to address the synergistic combination of MSI and BIM to assist fabrication and erection in the construction of steel structures. This research is aimed at resolving the problems of fabrication in the shop and erection at the jobsite. The goal of the research is to analy ze and to build a framework for the BIM decisionmaking model for fabrication and erection of steel structure construction. A detail sequence of fabrication and erection will be analyzed and tracked by using case studies comparing the traditional methods a nd BIM. The solution of each subproblem involves the following steps: 1. Identify and describe the problem with requirements 2. Review related work 3. Propose evaluation method 4. Propose and implement approach 5. Assess approach 6. Show the contribution Objective of Research The objective of this research is to create a BIM decision making model with the implementation in the erection of steel structures It is a web based system which is based on BIM, using manufacturing system integration (MSI) and other advanced projec t management methods The proposed model can fit the need s of the steel structure erection demands. The combination of BIM and other systems will allow all the data from BIM to be integrated with effective MSI management. In this case, the site manager can send purchase orders to the manufacturing machines to make the parts they need. The integrated system can follow the same sequence to make steel pieces as requested for the project. Using this system, the biggest benefit is to avoid carrying forward mist akes through the entire process from manufacturing to erection. This approach also saves time in the material and documents delivery It also helps in resolving problems at their first occurrence. In the proposed framework of the BIM and MSI system, the
64 i ntention is to synergistically combine the BIM system and the MSI system with the proposed framework. RFID is proposed to be implemented in the framework as the data management tool for data collection and integration. The framework of the synergistic sys tem will be validated in the fabrication and erection process of the steel structure construction. Modeling and Implementation RFID (Radio frequency identification) is a method of steel identification in the proposed research. This research suggests that R FID tags should be applied after the first step of fabrication when the major structural steel are cut and other minors (i.e. plates, angles, trusses) are fabricated S canner is used to scan all the piece s of the steel structure with RFID barcode s at leas t for main columns and beam members. After the job is finished each piece of information scanned will be translated into a serial code that represents the steel member. Then the data will be imported into the information system and the color of steel in t he BIM model will be changed. This serial code system is different from the bar code system, which is used in fabrication and erection by some companies. The code system is not just a tracking code, but it is also part of the proposed system. It has a broa der site management perspective, aimed at dealing with not only dayto day but also item to item activities. This method can be used for all steel parts, even for plates and bolts. The code can be developed by adopting an existing bar code system or by creating a new standard to reflect workflow or supply chain. Verification and Testing Parts of this research are based on the ideas from other scientists and researchers. Most of the methodologies have not been tested or displayed. All of these give us more challenges in verifying the model and result. The first step is to perform a comprehensive literature review and gap analysis, and identify what is missing. Then, with emphasis on the jobsite sequencing, scheduling and cost controlling, the model will be v alidated by using the following procedures:
65 1. Discover related research and collecting the data. 2. Digest Web metadata. Put it in computer model. 3. Provide search and navigation services and estimate query complexity. The result of each testing will be evaluat ed by the following methods: 1. Statistical report on collected metadata, 2. Real world usage using model case studies. This study selected two steel structure projects as examples to validate the system framework Each case will be run through the system fram ework for results. In the case study, the data will be collected from project cost, scheduling and supervision. By comparing case study results from the two projects, the success of the research model will be verified. Problems Release and Discussion In the following discussion, the following questions will be answered: 1. What are the p roblems in steel design and fabrication ? 2. What are the p roblems in steel erection ? 3. What can this research do and improve upon? To overcome the barrier, the key element is to use reference materials and first hand documents to develop a project model just for the end users. The framework of the model need not be a full size, universal model. But it could resolve questions and help in making decisions at least for one major co nstruction division. To achieve this target, the following steps were followed: The first step involved a comprehensive literature review and accumulation of data, tracking of progress, and monitoring the variables for two construction projects. This step also involve d preparing simulation questions to test the model. The data from the selected construction projects were used as the basis for the proposed model. The s econd step wa s to narrow down the major research scope. A large full fledged model may of fer inclusive functions and meet end users needs, but it is beyond the scope of this study.
66 The t hird step wa s to study the existing models and compare them to the proposed model. The purpose of the comparison is to strengthen and improve the proposed model to become a more effective model. The adoption of some successful features and modules from these existing models can reduce the cost and time to build up the proposed model. During the study, some of the sample models found was used as reference in de signing and developing the functions of the proposed model. Finally, real construction project data was used to test the feasibility of the designed model. After building the proposed model, the real project data was used in the tests which produced the e nd results to simulate the projects jobsite performance. The testing process is shown in Figure 31. Three main factors measuring this solution process: Benefit Fit; Technique Fit and Safety Fit. If any of these three conditions not fit, the decision woul d not pass to become a solution. F or multiple solutions, there are a process to innovation and combination each of them, then going to the final solution. ProcessSolution 1Yes NoInnovation Solution 2Yes NoInnovation Solution 3Yes Final Solution Selection Criteria Analysis and Calculation Benefit Fit Technique FIT Safety Fit Solution Selection Solution Portfolio Figure 31. Model s elections and s olution process Case Study Design In general, steel constructio n can be divided into four continual processes: structural design, detailing and estimating, fabrication, and erection/installation (www.aisc.org 2009). Steel fabrication is one of the most important processes in structure steel construction. Most fabricat ion jobs are done in a shop. Then the fabricated steel is delivered to a jobsite. For large -
67 scale projects, steel fabrication may take much longer than the erection process. Steel Erection requires many detailed plans, trained skills, and special equipmen ts and tools to finish it. Erection drawings show parts numbers and locations, connections, welding, drillings, and other details. The erection schedule includes hoists and crane schedule, shipping schedule, and job planning. The main erection checklist i ncludes: set up crane areas; work zones for each crane, or derrick; divisions for each derrick for shipping and sorting; every piece of steel erection and hauling arrangement; anchor bolts and embeds in footings; special equipment and tools rental and loading arrangement; power line and utility; special scaffolds, floats, needle beams and planks; securing of licenses, permits, and bonds; crews background check and job training; layout of electric power lines for hoists, welding equipment, compressors, hand tools, signal system, and lighting. Safety is an important issue in steel structure construction. The safety manager for the steel installation needs to check safety hooks, helmets and hard hats, safety belt, crane safety (space area, power line, load lim its, etc.), welding and cutting, loading and hauling, weather issue protection, and fall protection. In the case studies, the steps involved in steel construction w ere reflected, especially steel fabrication and erection. The framework of the proposed synergistic system shows the details in each step of fabrication and erection in steel construction. The details include: the major decisions to be made the input variables, the project specific constant, the related formulas and calculations, decision resu lt, etc. Since all of the factors are project specific, case studies will be designed to illustrate the functions of the framework of the system and to validate the framework of the system.
68 Contributions to the Construction Industry This research proposes a model that combines webbased 4D, BIM, RFID and MSI techniques. The BIM/RFID f ramework focuses on site steel erection and organization. The program is based on a multi purpose model, which uses RFID plus steel series code and color codes systems to differentiate between steel pieces, to help control the schedule of a project, and to describe the entire scope of construction. It relies on a 4D graphic scheduling to display real time steel erection information. It helps with planning jobs, verifying e rection information, controlling job sequence, site inspection, and other field related jobs. The proposed BIM/RFID framework could be used in the life cycle of a project. The significance of this BIM/RFID framework is that it helps minimize project mistakes. This framework deals with uncertainty problems, which is an area that needs a lot of investigation. If project managers can view the current project situation and predict the possible results in a virtual environment, it will be eas y for them to control the changes. In addition, these project managers can find out solutions to deal with the possible mistakes or errors.
69 CHAPTER 4 BIM /RFID FRAMEWORK ANALYSIS Decision N eed for T ypical S tructure P roject In the D esign S tage In the design stage, architects are responsible for collecting analyzing, and realizing the design intent s of the construction project. A rchitect s should maintain the documentations of project s and coordinate the related life safety and cod e compliance issues for construction project s Architects also updat e documents and information in digital format such as PDF, DWG, RVT or CAD (Hardin 2009). For BIM models, most software products support the functions to generate views from different perspectives. These views can be saved in different formats. At the design stage, project engineer s focus on the project physical conditions Us ing the proposed system as an example since it has the framework for steel structure fabrication and erection, the n if a project engineer uses the proposed system, the ir attention will focus on the physical conditions of the steel. In addition, the project engineer should consider the design requirements for other materials. For example, steel structure design will b e affected by the load requirements of the HVAC equipment, the lab equipment, and classroom equipment, etc. of a project. In this case, an architect needs to collect all the necessary information about the equipment and systems of the project. For a genera l contractor, if this is a design build project, the general contractor will be involved in the cost engineering and will contribute their expertise and experience in helping with the design. For the case study used in this research the steel fabricator ( as a subcontractor) worked on the shop drawings and on detailing the steel parts of the structure. The erector worked on the erection plan and the arrangement of the cranes; the protection of equipment; and the arrangements of the installation crew shifts The crane supplier worked on
70 the weather analysis and forecast; in addition, the crane supplier was responsible for crane shipment, installation, and coordination plans. Table 41. Decision s needed for a typical steel structure project Design need for typical steel structure project Architect Engineer General Contractor Subcontract ( F abricator) Subcontract (Erector) Subcontractor (Crane) Subcontract (MEP) Design Design and specify the scope of work Physical Condition and Material Cost and Management Shop Drawing and Detailing Erection Plan and Arrangement Weather and Crane Plan Plan and Arrangement Fabrication Shop order, work flow Detailing, Methods Control and Drawing Submittal, Planning and Scheduling; Sequence of Fabrication, Order M a terial, S ale or Keep; Steel Structure Adjustment According to MEP Equipment Requirement; Erection Schedule and Plan Change, Welding Schedule Layout Plan, Tie -Up plan MEP Shop Drawings; Buy out Delivery Delivery plan Protection Plan for Special parts Coordinate th e steel delivery plan with other activities Produce and adjust the fabrication of steel parts; coordinate the fabrication plan and delivery plan Road selection; Prepare and start erection; Coordinate erection plan and delivery plan; pre assemble Weather; Safety; Crane plan adjustment Finalize MEP delivery and installation schedules Erection Review Approve/D eny on -site project changes Protection for Special parts As-built drawings; coordination; monitoring schedules Produce and adjust the fabrication of steel parts; coordinate the fabrication plan and erection plan Site adjustment of the steel parts; safety control; quality control Sequence; add/delete the number of cranes or workers; protection; safety Coordinate work sequence with steel erection schedule; Welding Plan The mechanical, electrical, and plumbing (MEP) subcontractors worked on their individual plans and arrangements. In the design stage, the information provided by the MEP subcontractors was used by the architect s and engineer s for calcula tion and design purposes. If the project physical conditions, such the space, soil conditions, or intended usage, do not allow certain types of MEP equipment or layout design to be used in the project, the MEP subcontractors would have to adjust their desi gn drawings according to the project physical conditions.
71 For the design stage of the example project, steel structure design unarguably plays the most important role. The decisions made during the steel structure design affect other designs and should be done quickly and correctly. The following decisions need to be ma de to finish the design stage of the steel structure A ll these questions are going to be included in the typical decision making modules in the proposed system as selection menus or dialog w indow s Architects Decisions: What type of standard structural system material(s) to use? Wood Steel Concrete Masonry Composite Construction Walls and the Building Envelope What choices to make for the complex structural systems? Trusses Arches Rigid Fram es Space Frames Folded Plates Thin Shell Structures Stressed Skin Structures Suspension Structures Inflatable Structures Calculate or implement the following structural system selection criteria: Resistance to Loads Building Use and Function Integration wi th Other Building Systems Cost Influences Fire Resistance Construction Limitations Style Social and Cultural Influences
72 Engineers Decisions: Calculate loads on the building: Gravity Loads Dead Loads Live Loads Load Combinations Lateral Loads Wind Earthq uake Miscellaneous Loads Dynamic Loads TemperatureInduced Loads Soil Loads Water Design decisions to make on beams and columns Design decisions to make on columns Design decisions to make on trusses and truss analysis Method of Joints Method of Sections G raphic Method Soil and Foundation Soil Properties Subsurface Exploration Soil Types and Bearing Capacities Water in Soil Soil Treatment Other Considerations Foundation Systems Spread Footings Pile Foundations Designing Footings Retaining Walls Types of Ret aining Walls Forces on Retaining Walls Design Considerations Sample Decisions Design decisions on connections Wood Connections Species of Wood Type of Load Condition of Wood Service Conditions Fire Retardant Treatment Angle of Load Critical Net Section
73 Typ e of Shear Connector Spacing End and Edge Distances to Connectors Nails Screws Lag Screws Bolts Timber Connectors Miscellaneous Connection Hardware Steel Connections Bolts Welds Concrete Connections Rebar and Keyed Sections Weld Plates Shear Connectors Ana lysis of building code requirements on structural design Loading Allowable Stresses Construction Requirements Fireproofing Detailed design decisions for steel construction Properties of Structural Steel Types and Composition of Steel Shapes and Sizes of St ructural Steel Allowable Stresses Steel Beams Lateral Support and Compact Sections Design for Bending Design for Shear Design for Deflection Steel Columns End Conditions Design for Axial Compression BuiltUp Sections Open Web Steel Joists Analysis of Wind Loading Analysis of lateral forces Wind Design of WindResisting Structures Analysis of lateral forces Earthquakes Making selection from structural systems to resist lateral loads Bearing Wall Systems Building Frame Systems Moment Resisting Frame Systems Dual Systems Horizontal Elements
74 Building Configuration Torsion Plan Shape Elevation Design Analysis of Earthquake Loading Additional Considerations Overturning Moment Drift For an engineer, the desi gn and selection considerations are: Function Cost and Ec onomy Shipping Acoustics Assembly and Erection Fire Protection For an engineer, the technical considerations are: Connections Envelope Attachment Pounding Temperature Movement and Stresses Tolerances Stability Shop Drawing Review Construction Observation G eneral Contractors Decisions: Cost analysis about different sizes and types of steel materials that satisfy the architectural/engineering requirements. Which steel type(s) is/are more cost efficient in this project? What is value engineering about possi ble options in steel design? Fabricators Decisions: Do the shop drawings provide enough details for the steel structure? What types of connections to use: bolts, welding, etc.?
75 Erectors Decisions: How to install the steel structure? How many crews need to be arranged for the installation of the steel structure? Crane Operators Decisions: What weather will be expected during the installation of the steel structure? How many cranes need to be arranged for the installation of the steel structure? MEP Subc ontractors Decisions: What information does the architect and the engineer need for their design of the steel structure? What types or models of the MEP equipment should be used in the project? What are the load requirements the MEP equipment has on the steel structure, including dead load and live load? What are the room or space requirements the MEP equipment has on the steel structure? In the F abrication S tage The architect will focus on the shop orders of the steel structure of the building. The arch itect will also work on the work flow of the steel structure, including design coordination and construction administration. The engineer will review the details of the steel structure and methods of pre assembling and installation. The general contractor will work on the control of the construction administration. Before fabricator can start the production process, the general contractor should finish the shop drawing submittal, review, and architect/engineer approval process. The general contractor shoul d also work on the planning and scheduling of the steel structure. The fabricator has to specify the scope of work and parts for shop work. The fabricator should communicate with the architect, the engineer and the general contractor is regarding to the st ructure steel connection and welding methods, sequence of fabrication, shop drawing submittal, and fabrication schedule and plan. For an erector in the fabrication stage, the
76 subcontractor will work on the erection schedule and coordinate the erection sche dule with any changes on the steel structure design. The erector will also work on a welding schedule to finalize the details of the steel structure installation. The crane operator will work on the layout plan of the cranes. The crane operator will also provide a tie up plan for the sequence and coordinate multiple cranes. The MEP subcontractors will prepare the MEP shop drawings The MEP subcontractors will also work on submission and review processes. The MEP subcontractors will decide on whether to per form their scopes of work by themselves or buy the service from outside. In the case study, f or the project in the steel structure fabrication stage, the decisions made involve a great amount of money and remarkable length of time duration. The following decisions need to be ma de to finish the fabrication stage of the steel structure: Architects Decisions: Are the steel structure shop drawings correct? Do the steel structure shop drawings coordinate with other shop drawings, such as MEP shop drawings? Are the work flow and communication of the steel structure appropriate? Are the design coordination and construction administration of the steel structure appropriate? Engineers Decisions: Are the steel structure shop drawings correct? Do the steel structure shop drawings coordinate with other shop drawings, such as MEP shop drawings? Are the details of the steel structure shop drawings appropriate? Are the methods used in fabrication, delivery, storage, installation, and inspection appropriate?
77 General Cont ractors Decisions: Has the shop drawing submittal, review, and architect/engineerapproval process been finished? Can the submittal review and approval be finished before the start of the steel fabrication? Has the scheduling of the steel structure been finished? Has the cost arrangement of the steel fabrication been completed? Has the steel materials been purchased and are in place? When will the steel fabrication be finished? Should the steel structure parts and assemblies be delivered all at once or in stages? Have all the value engineering ideas been analyzed and discussed? Fabricators Decisions: Have the reviews on shop drawing submittals been finished and approved? Have the fabrication schedule and plan been completed? Has the sequence of fabricat ion been finalized and followed? Are all the steel materials for the fabrication ordered and in place? If time is not allowed, should part or the entire fabrication job be sold out to the outside steel company or companies? According to the MEP equipment r equirements, has the steel structure adjustment been finished? According to the availability of the steel materials, has the adjustment to the steel parts been finished? In order to save the site installation time, are there any other possible ways (differ ent from the drawings) to fabricate the steel parts? Are all the pre assembled parts finished? Erectors Decisions: What is the sequence of the erection of the steel structure? What is the sequence of the welding on the structure?
78 Crane Operators Decisio ns: Has the layout plan of the crane been finished? Has the tieup plan for the sequence and cooperation of the multiple cranes been finished? MEP Subcontractors Decisions: Have the MEP shop drawings been prepared? Have the MEP shop drawings been submitte d? What are the review decisions on the submittals? Whether perform their scopes of work by themselves or buy the service from outside? In the D elivery S tage Delivery is the key of Supply Chain System. Time, route, and quality are three components of delivery. The decision making for delivery also focuses on right on time, right routes, and right quality service. The detailed delivery analysis focuses on space arrangement, loading efficiency, tractability, and safety in conveying. For the example project in the steel delivery stage, the decisions made should cooperate with erection work and other trades. The following decisions need to be made to finish the delivery stage of the steel structure: Architects Decisions: Has the review on the delivery plan b een completed? Engineers Decisions: Has the protection plan for the delivery of the special steel parts been reviewed and approved? General Contractors Decisions: Has the delivery plan been reviewed? Has the delivery plan been discussed with other relative subcontractors? Has the site utilization plan been designed, discussed, and agreed by all the involved subcontractors?
79 Fabricators Decisions: Do the steel parts need to be adjusted? Have all the steel parts been produced? How to coordinate the fabrication plan and delivery plan? Erectors Decisions: Which roads to select as the delivery route? Has the steel delivery been finished? Has the preparation of the erection been finished? Does the erection plan coordinate with delivery plan? Do the steel parts need to be preassembled? Crane Operators Decisions: What is the weather forecast for the next several weeks? Has the safety procedures been analyzed and well understood? Does the crane plan need any adjustment? MEP Subcontractors Decisions: Have the MEP delivery plans been finalized? Have the installation schedules of MEP scopes of work been finalized? In the Job S ite E rection S tage Jobsite uncertainty impacts the steel erection process and causes changed results in decisionmaking. Uncertai nties include: schedule delay (fabricator, equipment, MEP or delivery), labor absence, OSHA penalty, fabrication mistaken, material missing or shortage, budget cut or drawing change, accident, or damage, etc. The architect in this stage is responsible for reviewing digital punch list and project closeout document for owners, engineers and contractors use.
80 For the example project in the steel erection stage, the decisions made affect the cost, duration, quality, and safety of the work and other trades. The f ollowing decisions need to be made to finish the erection/installation stage of the steel structure: Architects Decisions: Have all the project change orders been reviewed? Are the change orders approved or denied? What are the influences of the change or ders to the steel structure construction? Engineers Decisions: What procedures should be taken to protect the special parts? General Contractors Decisions: Have the as built drawings been maintained? How to coordinate the steel erection with other trades work? How to monitor and control the steel erection process? Fabricators Decisions: If fabrication is in stages, how to produce and adjust the fabrication of steel parts with the installation requirements? How to coordinate the fabrication p lan with the erection plan? Erectors Decisions: Are site adjustments required on the steel parts? How to cut or fix the steel parts to fit the locations? How to control the safety management on the jobsite? How to control the quality of the steel structure installation? Crane Operators Decisions: What is the sequence of the installation of the steel parts? If one or more cranes are added or deleted from the site of the project, what will be the impacts on the time duration or cost of the work?
81 If one or m ore crews are added or deleted from the site of the project, what will be the impacts on the time duration or cost of the work? How to protect the workers, the cranes, the surrounding materials and equipment, and other things existing on the site during er ection? How to implement the safety procedures? MEP Subcontractors Decisions: How to coordinate work sequence with steel erection? What are the requirements the MEP equipment has on the welding plan? Components of the BIM/RFID Fr amework In the proposed system, a BIM component has two information sources to support the decision making. One is database; the other is model base (See Figure 4 1). Each source gives BIM information and technique support. The proposed system will provide the following data for decision makers to make optimum decisions : (1) c onceptualizations, such as a plan or financial support; (2) d ifferent decision m aking processes and decision t ypes, all involving activities for intelligence, design and choice; (3) a variety of memory aids; (4) a variety of styles, skills, and knowledge applied v ia direct, p ersonal control. The Decision Support System uses the corresponding IT language T here are also four functions in it: (1) representations; (2) o perations for i nte lligence, design, and c hoice; (3) a utomated m emory a ids; (4) associate jobsite director Intelligence, design, and choice are well known paradigms which can help classify the operations used in decision making. (Sprague 1982) In the entire proposed synerg istic system, the decision support system and the BIM system are integrated together. As shown in Figure 41, the proposed synergistic system in thi s research is composed of three modules: the database module, the Building Information Model module, and the model base module. In the database module, i nformation can be extracted, captured, or manually entered from the information pool into the database of the synergistic system.
82 Information Pool Data Base Model Base Software St Finance Marketing Personnel Other External and Internal data sources Manufacturing Economic Data Cost Data Old Project Data Building Code Employee Data Strategic Models Tactical Models Operational Models Model Blocks Model Subroutines Engineer Software Management Software Other Softwares (GPS, GIS, RFID etc.) Design Software Building Information Model Data Base Model Base Extraction Integration Capture Entry Figure 41. BIM and s upporting b ases
83 The information pool includes m anufacturing database, company financial database, marketing database, personnel or human resource database, and other external and internal data sources. Here, the database includes the structured data and the data source includes the unstructured data. T he databases or data sources in the information pool are not constructionproject specific. In order for the information to be constructionproject specific so that it can be used by the BIM model of a project, the information in the information pool needs to be processed and organized into the project database. The project specific database includes economictrend data, cost data, project history data (which is the data from old similar projects), applicable building code, and project related employee dat a. After the needed information is pulled from the information pool, users can find the information from the BIM model. The BIM model is a web based 3D/4D m odel The BIM model is a combination of the webbased search engine and the visualization model. Fo r decision making support purpose s the synergistic system needs to have the model base module. The model base module is composed of various model bases, such as strategic models, tactical models, operational models, model blocks, and model subroutines. These models in the model base is supported by the integration of different software, including but not limited to, design software, engineering software, management software, and GPS, GIS, and RFID, etc. Computing and management modeling design have been i mproving the efficiency of the construction industry. Computer aided design software and project management software focus on different sequences and stages of construction The software products help us achieve a paperless work environment. Figure 42 sh ows the system relationship with decision making frame. BIM is a combination of all the project data which allows users to gather all the information they want to
84 know, including cost and schedule information. The goal of MSI is to bring together the component of subsystems into one system and to ensure that the subsystems function together as a system. In information technology, systems integration is the process of linking together different computing systems and software applications physically or functi onally. Figure 42. Systems relationship with decision making frame Current MSI research addresses topics spanning over supply chain, system integration, metrology, simulation, ontologism, product data green manufacturing, lean manufacturing, and sustainable manufacturing. All these are grouped under five categories : design and process, Enterprise systems, Manufacturing Simulation and Modeling, Manufacturing standards metrology, and system Integration for Manufacturing Applications. (http://www.nist.gov/mel/msid/) Figure 43 shows how BIM is interrelated with all those three major performances of construction. Construction management includes management, scheduling and planning, and cost. The major research field between Scheduling and planning and Cost is supply chain management which works for short the time duration and save money. Cost control is the major Decision Making RFID BIM 4D CAD and VRM MSI
85 research field between Management and Cost. The most important part is the user model and dec ision between Management and Scheduling and planning. Figure 43. BIM functions in project m anagement c oncept BIM software was developed as a response to the need of information that can be shared, added to, altered, and d istributed among the design team. Primavera (www.primavera.com) and Microsoft Project are the most used construction scheduling software. Both of them are compatible with Navisworks TimeLiner. Any scheduling software that can produce an MPX or a Primavera version 5 file can have its static schedule linked to a BIM schedule through Navisworks. (Hardin 2009) RFID Integration in the Proposed System The significant contribution of RFID is the use of its data in tracking the structural steel member. The tracki ng distances are different when using different RFID tags. A passive tag has the s imilar distance as barcode. It depends on readers power that may extend to 20 feet at most. But the tag can reach up to a distance of 300 feet when using an active tag with battery. The code associated with each member is unique and stays forever if it is not changed. It keeps RFID exclusive and secure Cost BIM User Model Decision Making Management Cost Control Supply Chain Scheduling Planning
86 when databases are safely used. The cost has become much cheaper as thes e production has been increased and the size of tags has also become much smaller. The contribution of this research to the current state of RFID integration in steel structure construction has two parts: First, a usage model is created to link RFID data with BIM. This will improve its functions, such as data input, searching, sharing, and retrieve. (see Table 4 2) Then, the data can be used to develop a real time 4D BIM jobsite management system. Currently, RFID in building construction are still focused on supplychain and movement tracking. BIM is an innovational model for the entire construction industry. It provides the tools for creating a paperless project environment and high level visualization imaging. But it is still a challenge to BIM users because BIM has not widely been acceptable by construc tion industry yet. The following are the advantages of RFID: RFID has a tracking function to keep material together; RFID has memory function to keep material information anywhere; RFID can be easy carried and glued on material; RFID can be read by di fferent readers and users; RFID can secure material safety by alerting a gate alarm system; RFID has been used successfully used for 20 more years; RFID has digital information which is easy to be transported and stored to a PC or a PDA; RFID has ample me mory space which allows it to save as much as information as needed; RFID is an affordable technology. RFID as a tracking technology has been widely used in many fields including some successful practices in construction projects. Few cases have been rep orted as using both RFID and BIM in construction projects. This is a new research field and has great potential. The contributions that RFID can make in construction are: Help with BIM Help monitoring the Supply Chain Help the Fabricator Piece build up Help the Erector Identify/Locate Member Help the MEP contractor Identify Piping and Pieces Help the Finisher Find members and their Location
87 Table 4 2. Integration of RFID technology by steel frame building design and construction companies Software Main User Advantage s Disadvantage s Using RFID AutoCAD Designer It become universal design tool after more than 2 5 years (since 1982) develop and improve. Professional software with a long learning time; imaging only without man a gement function and detail connection Show the corresponding Components Takla Structure Steel Designer, Fabricator Erector A good BIM tool. Very good for steel and precas t con crete connection detail. It has 4D model supporting, schedule managing, Other model combination (IFC DWG, DXF, DGN ), report reference model information functions. It has some design function but not better than AutoCAD and Revit. Less function in management stage when use it in general contractor office. No community function. Big cost. Benefit all its software in detail information input and output. It can develop a real time 4D simulation or field implementation. Much more repot detail. Revi t Structure Designer, Contractor and Subcontractor Functional tools and easy to learn than A uto CAD for other background than Architecture 3D model is good for BIM user. It has better section and elevation plan, quantities and Energy functions. It has le ss detailing information for structure steel connection and MEP connection, without 4D function. Benefit to its design components. It can develop more functions with information input and retrieve. Tracking members and more detail for quantities report. D esign Data (SDS/2) Fabricator, Erector Detailing system standard, automatically Design Connections, use framing plan approach to detailing Not good for other stage works than steel structure detailing Giving a possibility to share information with more use rs. Easy input and output data of components, developing a real time field tracking system Vela system Contractor, Subcontractor BIM supporting. It has field safety control, scheduling, document sync, materials tracking, punch list and field report functi ons. Less design and 3D functions. Material tracking software only records the report not a really tracking. Improving it a better tracking and document sync function. Improving all its functions. The other contribution of this research is to simulate a system that uses RFID and Geographical Positioning System (GPS) technology to achieve a real time tracking of components and track building progress through the entire project. It includes a framework
88 designed to locate the column and beam members positions and to track their progress in the construction process. GPS technology has been used in transportation and surve y activities for a long time. GPS technology has revolutionized many areas of peoples lives; but it is simply too expensive to put a GPS receiver on every piece of material that is shipped. RFID electronic tags can be attached to almost all packages in sh ipment. Unlike current bar coding systems, RFID electronic tags do not require a visual scan and can carry significantly more information. Currently bar coding is almost everywhere, but it requires a close and accurate visual scan by a bar code reader. It is simply too slow and often inaccurate. RFID tags, on the other hand, only require that the package be within radio frequency range of the RFID receiver or RFID interrogator. (Russell 2007) On construction jobsites, GPS has just begun to be used on ground level and dump truck or equipment tracking. Using GPS and RFID building components can be tracked from the moment they arrive on the jobsite to the moment when they are installed. Two technologies, RFID and GPS, can be used to locate steel column inst allation. In this research, the author has developed the decision making model to improve the jobsite work efficiencies that use GPS and RFID technology. The model should have the functions for tracking materials and site layout and steel erection and all ow for the use of GPS and RFID work for more erection sequences and different stages. A case study involving a 1,230 Megawatt twin unit coal power plant in northeastern United States illustrates the application of GPS and RFID technologies on a constructi on site. A large general contractor has implemented AutoID Technologies in a power plant construction
89 project to streamline the process of locating, verifying and delivering of pipe spools from large lay down yards to the construction site when needed duri ng the construction sequence. Prior to the implementation of the AutoID Technology the contractor estimated that it would take, on average, a two man pipe fitter crew one and half to three hours to locate, verify and flag pipe spools in the various lay down yards. After the implementation of the AutoID Technology the same crew was able to print out a map of the lay down yard or use a handheld device to find the exact location of the pipe spools every time. The new technology resulted in an estimated saving of roughly $3 million for the project. The general contractor has now begun using the technology to tag all structural steel components on the site and has plans to use the re usable RFID tags, which have a life of 5 to 7 years, for other construction mat erials on this project and other future projects (http://www.atlasrfidsolutions.com 2008) ENR (April 2008) had a example of RFID and A UTOID t echnique used on another US construction project, the 84,000seat Meadowlands stadium project in New Jersey. This $1 billion project, a just in time system, used GPS and RFID tracking for managing the delivery of 3,200 pre cast concrete risers which were being manufactured off site and assembled to form the bowl of the 84,000 seat stadium. From design to placement stages, the pre cast concrete components were tracked using RFID. It was estimated that project saving were $1million and that there was a gain of 10 days in t he project schedule. This job was done by Skanska USA Building Inc. using software from Tekla Inc. and Vela Systems. The structure model was turned into a construction model by importing scheduling data from Primavera systems P5 and using Autodesks Navisworks to run clash detection (Sawyer 2008).
90 RFID and GPS on Site to Improve BIM Functions The proposed system can be used as the location coordinates for the job site. It is associated with the methods such as laser equipment (i.e. Robotic Total Station) and Global Position System (GPS). The early laser equipment can emit a laser ray around the jobsite and a receiver can be used as the ground level. To install a steel structural member, four essential components are need in advance. They are the identified member, 3D position data, the party conducting the operation, and the connecting members (see Figure 4 4 ). RFID can measure identified member and serve connection data, GPS can measure 3D position data. RFID data is the safe and durable solution for steel components. RFID tags are attached onto steel members giving a rough layout location of members. 3D position data is the location identification of the steel member. GPS receiver or tags are satellite measurement by Global Position System and it can make an accurate position point by its 3 segments: space, control and user. Laser based 3D solution als o work to measure an accurate position. 3D Position Measurement (Laser Station and GPS) Identified Member (RFID) Members Connection (RFID and GPS and Laser) Operation Party (Laser Station and GPS) Figure 44. Steel e rection c omponents The party conducting the operation includes the crane operator and equipment. A crane GPS solution can link the 3D position data and with the party conducting the operation in a
91 single system. The RFID and GPS all can be read from a mobile reader (RFID) or control sensor box (GPS) installed in the crane operator cabin. RFID system and GPS system can work well at the same long wave radio frequencies between 285 kHz and 325 kHz. These frequencies are commonly used for marine radio, and are broadcast near major waterways and harbors. The connecting members information consists of other members 3D position data so that the connector can use the right bolts or level welding plate on the right position to install the member at the correct angle. As built checking is one function of laser station. This function can be used for column splice connection checking as well. An example will be used to explain how this RFID data when associated with laser station and GPS can help in steel installation and in checking the erection plan. RFID data arrives on the jobsite after fabrication. The steel components with GPS and R FID tags are tracked after leaving the fabricators storage. A just on time system arranges the arrival time and crane operation plan. The site GPS equipment begins to work on the location survey of each component based on the RFID data sent from fabricators PC. The azimuth data will be recorded by each RFID sequence. A truck enters the gate with an RFID reader on it. At the same time, a crane begins to hoist the members according to the erection plan sequence. The crane operator looks at the GPS and RFI D data in the 3D control box. Then the operator follows the order to move the first column to its GPS position (see Figure 4 5). It shows the time for the first column to be set on the base plate. The GPS system helps the operator to adjust the column pos ition while the 3D laser station as buil t system is checking its vertical and horizontal level to make sure that the column has been installed according to plan. After the first column stands up, a GPS sensor will be attached onto it as a reference GPS poi nt.
92 Figure 45. Examples of RFID and GPS use in s teel s tructure e rection (Ergen 2006) The rest of the steel components are erected by using the same methods. GPS transmitters are used to help the operator measure the positions of components. They are all built up by using RFID data so that the exact locations of the connecting members are known. The RFID tags are collected for reuse and their data were transferred into a 4D model. In th is example, sequence one is going to finish all works and sequence two has just finished columns. The welding connecter is reading the last beams RFID data by PDA. It says this beam has a 3/4 fillet weld connection with column RFID# 1C10 and a shear plate PL1030s location (GPS #3) on outside face for support of beam RFID # 2B30. The connecter uses GPS data receiver to find the PL1030s mark and weld it. The deck foreman is working on
93 GPS e quipment and data to measure the beam and girders level, using RFID data to arrange the layout process and orders. A plumbing foreman uses Robot MEP Station to measure the plumbing level and set hangers as specified by the RFID data. The n he uses GPS for the piping hose connection and sinks location on the floor. In the 84,000 seat Meadowlands, NJ stadium projec t This $1 billion project had a just in time system, which used GPS and RFID tracking system. The project had deliveries of 3,200 pre cast concrete risers manufactured and assembled to form the bowl of the 84,000 seat stadium. From design to placement stages, the pre cast concrete components were tracked by RFID (ENR 2008).
94 CHAPTER 5 BIM /RFID FRAMEWORK IMPLEMENTATION In thi s chapter, the author may discuss in detail about the decision framework of integrating RFID with BIM models. Figur e 51 i s a flowchart of RFID Data Implementation. Based on the flowchart, the methodology for using RFID technology for structural steel comp onent s such as a steel beam or column will be discussed. T he use of RFID in the BIM system will also be discussed, in addition to how the decision support systems will transmit data read from RFID, retrieve the requested information, integrate the inform ation in analysis process, and update the BIM project model when a decision is reached. In this chapter, the erection of a steel beam is used as an example in order to show : How the details about structural components are stored in RFID database in the chi p memory What metadata or types of data need to be stored in the chip memory in each step of steel construction What meta data or type of data need to be stored in BIM database in each step of steel construction H ow the RFID data is read from the chip me mory to BIM database via wireless Internet in each step of steel construction H ow the decision making or support systems can use the information retrieved from the RFID database for analysis, simulation, calculation, and selection of useful data The constr uction jobsite has many uncertain conditions and risks. For example, site condition change (ground sink, flooding, weather change); schedule delay (caused by Fabricator, Equipment, or MEP); labor absence; local or OSHA penalty; fabrication mistake; heavy e quipment loss by theft; material missing; budget cuts; unexpected damage; etc. It is difficult to claim that a result proposed by the system is the best one or most suitable to the project conditions. But it is possible and feasible for the system to gene rate a result which will satisfy the complicated criteria of the evaluation module of the system. The suggested result
95 would have great potential of sav ing construction time, decrease cost, improve safety record, or achieve better quality in the end of the construction process. In this chapter, the author will use a steel beam component as an example and show the logic behind all the information retrieval and updating process. In the steel structure erection process, there are many factors or variables aff ecting job performance. The variables in the process include: time, cost, quality, safety proc edures, building code, workers experience, etc. Different projects have different weights associated with the se variables. For example, in a timecritical project, the time issue will be the most important factor, and hence will have the most weight. For a power plant construction project, safety will be the most important one in all the variables. Generally, steel construction is a complex manufacture delivery in stallation process with great probability of failures or errors. The time, cost, and safety (Building Code and OSHA r egulation) are always the first three considerations for a project. Those three factors can also be used to evaluate a projects performanc e and quality. BIM /RFID Framework Description BIM users identify local solutions and provide a richer, more specific design at the early stage. This requires more thought and effort (expertise) than what is required when professionals design projects using typical 2D standard practices However, it leads to higher quality designs through more detailed consideration of alternatives, and drastically reduces the effort required for production detailing and preparation of shop drawings. (Sa cks 2008) The decision making model uses BIM and RFID data on the erection status of steel members to identify solutions and reduce the conflictin g information derived from different drawings. Existing BIM tools have f unctions to satisfy project requiremen ts such as estimating and scheduling. BIM is strong at designing and weak at project control and decision making.
96 In a test of BIM tools by the Eastman group for BIM exchange standards for IFCs t hey found a broad spectrum of capabilities and limitations in BIM In most cases, almost all of the geometry was transmitted, with local specific errors that could be corrected. However, the piece count of the model changed. Importantly, all of the exchanges in th at example allowed only static, noneditable geomet ry exchange; editing on the receiving application required re building of the pieces. There was also a wide variety of mappings between internal model objects and the IFC objects used to represent those (Sacks 2008) At least part of these problems can be solved by using RFID data in conjunction with BIM RFID is not only a good identif ication tool, but also a data storage tool with a limited size of memory. M ost construction material s can be identified by us ing RFID tags Figure 51 shows how RFID can be used in BIM for component tracking. RFID attached to each construction material and represent them in the BIM model for construction process. RFID works for all BIM components One single and unique set of identification codes is used throughout the BIM m odel of a project. This marked identification helps in tracking the building components and makes using the BIM model to do that easier. Steel Members RFID Other Parts MEP Parts Revit 2009 Precast Concrete Connection Parts Material BIM Tools Vico 3D CAD Takla Navisworks BIM AEC VRML IFC CIS/2 Format CAD BIM Converting BIM Decision Making Decision Support CNC MDS DDS JDS SDS Figure 51. RFID us ed for BIM components
97 Steel fabricators use different identification methods for steel member s. Sometimes fabricators use their traditional ways to identify steel members. For example, W12X40 is a marker of column/beam wide flange shape steel. O n a project, wide flange steel is commonly selected for structural uses. When a user searches for steel components and enter s W12x40, BIM tools, such as Revit and Navisworks, will show all the same members that are used in the project and be able to show them in the 3D image view. W12x40 are only symbols for these members. In BIM tools, W12x40 column at the spot of C3 (the intersection of column line C and column line 3) has no difference with the W12x40 column at the spot of B2 (the intersection of column B and column line 2). RFID technology helps to distinguish the W12x40 members individually. In this sense, RFID enriches and complete s the information available for steel members. Each W12x40 steel member is differentiated by its location, date and shop of made, connection features, and so on. In this case, each member has a special serial number as its ID and is saved in its RFID tags memory. To link with the system to a jobsite or an AEC office need a cable network or wireless transmitter is needed to transfer RFID information to a central database. On Line Analytical Processing (OLAP) can be used for essential business applications (including sales and marketing analysis, planning, budgeting, etc.). Unlike typical enduser applications, OLAP products are regularly called upon to process large amounts of periodically refreshed data. Figure 52 ( Xie 2005) s hows the process of external data connection to an OLAP system. A w eb based information system gives OLAP widely operation field. The contribution of OLAP in this research is in the calculation process when using model for decision making.
98 Data Generating Events Host of Operating systems Data Warehousing Environment OLAP System Figure 52. Process of external data connection to an OLAP system (Xie 2005) BIM /RFID Framework Components and Relationship Chapter four discussed the detailed composition of the proposed synergistic BIM and RFID system. The synergistic system is built on the existing software systems. Figure 5 3 shows the proposed synergistic BIM /RFID framework which is supported by three main components: Manufacture Information System (MIS), Web Base BIM Control System (WBCS), and Decision Support System (DSS). BIM testing is a functional block that includes M athematics, Statistic and other methods, to check data usability and decision feasibility. The Decision T ree is a very useful method to help managers making decisions. Much software ha s it in functions, like ILOG CPLEX, Tree A ge, @Risk, DPL 7 and Microsoft Dynamics These modules have digital results to serve the next level information system module s such as Design Decision System (DDS), Manufacture Decision System (MDS), Supply Decisio n System (SDS) and Jobsite Decision System (JDS). Refreshed data after testing and OLAP processing are output to model based decision supporting systems. In this sequence, the BIM /RFID framework is tested and data result s are ready to be used to make the optimiz ed decision. MSI integrate s the information and simulation systems to develop an operational BIM environment. The systems integrates the supply chain sys tem product data and sustainable manufacture, VRML or other simulation tools, BIM 4D model (such as NavisWorks and Vico), online analytical processing, and decision tree and other decision software.
99 The web based 4D BIM control system integrates the supp ly chain system product data and sustainable manufacture, BIM 4D model (such as NavisWorks and Vico), online analytical processing, real time jobsite control system, and decision tree and other decision software. T he decision support system (DDS, MDS, SDS and JDS) integrates online analytical processing, real time jobsite control system, and decision tree and other decision support software. All these real time jobsite control system, decision tree and other decision software, etc. in the third layer is the middle ware between the proposed synergistic system and the basic data collecting and organizing tools and systems. The bottom layer of Figure 53 shows the basic data collecting and organizing tools and systems. These technical tools include buildin g code and safety regulations, BIM 3D files (such as AutoCAD 3D, Revit, NavisWorks, CIS/2), Project Scheduling Files (such as Microsoft Project or Primavera files), Web based PDA communication technique, and GPS, RFID and other laser identification techniq ue. The lines between the third layer and the bottom layer indicate the relationships between the middle ware systems and the project specific files and data. The Process of BIM Implementation Brad Hardin is a founding partner of BIM consulting firm Virtu al Construct Lab. He noted that in any organization a BIM team usually has to follow ten critical steps to be successful in the implementation of BIM (Hardin 2009) : Step 1: Identify a BIM Manager Step 2: Develop an Estimate of Cost and Time to Implement and Use BIM Software Step 3: Develop an Integration Plan Step 4: Start Small Step 5: Keep the Manager Trained Step 6: Support the Manager by Starting a Department Step 7: Stick to the Plan but Remain Flexible Step 8: Create Resources Step 9: Analyze Implementation Step 10: Monitor New Software Proposals and Industry Trends
100 Web-based RFID 4D BIM Control System GPS, RFID and Other Laser Identification Technique Web-based PDA Communication Technique Manufacture Integration System VRML or Other Simulation Tools Real Time Jobsite RFID Control System BIM 3D File (AutoCAD 3D, Revit, NavisWorks, CIS/2) Project Scheduling File (Mics Project or Primavera) BIM/RFID 4D Model (NavisWorks, Vico) Supply Chain System Product Data and Sustainable Manufacture Decision Support System (DDS, MDS, SDS, JDS) BIM/RFID Decision Making Framework On-Line Analytical Processing Decision Tree and Other Decision Software Building Code and Safety Technique Level BIM Control Level BIM Integration Level Figure 53. BIM /RFID framework c omponents and r elationship
101 The ten progress steps are very good for enterprises transforming from traditional workflow to a BIM workflow. S teel structure construction is similar to most other manufacturing industr ies. I t has a special and standa rd erection workflow. Figure 54 shows a traditional erection flow chart for structural steel. In this workflow chart, the actions are what users do in a normal traditional process for steel erection. BIM changes t raditional erection methods BIM tools a re suitable for every construction process covering from erection plan to sequence management, from estimating and scheduling to site monitoring and inspection. In every project, some exceptional change s may happen. With few exceptions, there is no unchanged schedule or on time project delivery in construction projects. So it would be im possible to make a universal decision model that works for any construction projects in whatever stages or applicable to any RFI and RFC actions. To creat e a useful framewo rk of decision making process and to analyze factors of the process can help BIM users to make decisions. The process and factors show the relationships and functions of AEC members and they can make easy decision s with the help from a transaction of BIM d ecision tools. To follow this erection work flow, BIM works with different needs of the workflow actions For example, a crane on site is an action that connect s with erection, crane and safety plans. The BIM /RFID decisions mak ing process is in determinin g how the manager can arrange the crane on time, whether or not the weather is acceptable, whether the crane is in a safe position, whether the project ha s the right number of machines and whether cost is affordable.
102 Crane on Site Steel on Site Unload Shake out Hoisting Sequence Bolting and Welding Anchor Rods Leveling Plate Erection Drawing Upload Column 123 Erection Order Connecting Plan Preliminary Bolting Crane Plan Plumbing Up Safety Cable Column Base Plate Upload Column 123 Temporary Bracing Girder First Columne Bolting and Welding Bracing Lateral Stability Column Splicing Perimeter Safety Cables Welding Shear Studs Roofing Inspection Fire Proofing Sequence 1 Sequence 2 Sequence 3 Sequence x Slabs Figure 54. Tradition al e rection f low c hart
103 BIM /RFID Framework As shown in Figure 55, the BIM /RFID Fram ework has three parts: Data Base, T esting Center, and Model Base. The three parts are integrated together and provide analysis, calculations, simulations, or even decision tree results for users to make optimized decisions. To illustrate the use of the syn ergistic system described in Figure 5 5, the whole process of a user starting from the intention to look for a decision and ending up with an optimized decision made is discussed The process is a cycle. Each step of the decision making process is saved i n the appropriate database. When a decision is reached, the result ing decision can also be saved in the database of the BIM/RFID framework as indicated by the dashed arrow in Figure 55 Decision Need JDS SDS MDS DDS ... Decision Tree Simulation Calculation s Experimental Analysis Output TESTING CENTER Project Cost Building Code RFI Documents RFID Databae ... Input DATA BASE MODEL BASE BIM/RFID Framwork Make the Decision Figure 55. BIM /RFID F ram ework a rchitecture BIM Data Base The database of the BIM /RFID Framework proposed in this research is not limited to one single data format. The data format could be M S Excel data for project cost or budget or i t coul d
104 be text data, word file, or Adobe PDF format for building codes. It could be in an Oracle database for employee data or i t could be in HTML format for ma r keting information. Usually, there is no connection between the databases of B IM/RFID Framework including all information and data collected from past projects, building a dministration supplier, market, etc. When a user of the BIM/RFID Framework system needs to make a decision, they will first go to the related databases and retriev e the data needed. BIM Testing After the needed data are collected from various databases, they will be sent to the testing part of the system. The testing center is a function block having the intelligent and automatic transacting function. It can use intelligent decision information system. It also serves as center for information collection, calculation, analysis and simulation. One or multiple testing methods can be used. During the decisionmaking process, decision support systems may request more databases than the ones already selected and opened by the user before. BIM Model Base In Figure 5 5, when the decision is made, it will be processed by the related software products to either demonstrate the changes or take actions. D ecision support system s of BIM /RFID framework include s : Design Decision System (DDS), Manufacture Decision System (MDS), Supply Decision System (SDS) and Jobsite Decision System (JDS). Examples of DDS include AutoCAD, Revit, Micro Station, etc. Wh en the design is eventually decided to be changed, the change will be made to the BIM project or other DDS files. After the design change is finalized in the BIM project model or other DDS files, the change is recorded in the system That marks the end of making decisions. Then the BIM /RFID Decision Making system can be used again to answer other questions.
105 Figure 56 shows the BIM /RFID network and the relationship s between the MSI, decision making model and BIM components. The main function of the MSI is to assist the BIM /RFID system with decision making. Figure 56. BIM /RFID Framework network BIM /RFID Framework Implementation for Steel Structure Project Knowledgeable BIM Team A knowledgeable BIM team is the key requirement for successful use of the BIM /RFID Framework First of all, BIM team members should know and be skillful with at least one BIM tool. They should be familiar with construction processes. Pr eviously in this C hapter, the ten steps to successfully implementing BIM were listed and they should be followed. Using RFID in the BIM /RFID Framework From above research and analysis to RFID, the BIM /RFID Frame work will use RFID to assist with its advanced functions in member verification and information tracking. The implementation of RFID in steel structure construction can improve construction quality and save time and cost. Supply Chain Sustainable Manufacturing System Integration MSI Model of Design Decision System (DDS), Manufactur e Decision System (MDS), Supply Decision System (SDS) and Jobsite Decision System (JDS) BIM Cost and Estimating Fabrication and Erection Scheduling and Planning Design Tools Delivery Decision Making Model 3D CAD Navis works Primaver Excel Vico Mic ro s oft Project Revit Timberline Tekla VRML Innovaya GPS RFI Adobe Google Sketch up Google Earth Simulation Revit Google Earth
106 Design Decision System (DDS) is a system that support s a designer to make a design decision. All design features can be repre s en ted by RFID layers. The material feature layer includes information such as loading, tension, h eat resistant condition, and bending feature s of materials. Some layer names are self explanatory, including: weather layer and material layout location layer P olice layer includes information such as OSHA regulation and building code Design feature layer includes information such as building type, design style, and zoning information S upply chain layer has information such as traffic information, weather, road condition, and deliver information C ost layer stores the estimat ing of different layers cost There are other layers for sequences of projects All these layers as BIM components can be used to make decisions on design, manufacture, suppl y, and installation They can help i n simulating building process and building up a building structure immedia tely if the cooperation information were given. In the near future, RFID c ould be combined with construction robots Figure 57 shows the RFID using data flow for BIM /RFID Framework decision making process. These data can be used without testing module be cause they are m ature data which had been acceptable for the user. But those changeable and uncertain data still need to be test ed by BIM /RFID testing systems. RFID database has many data layers, such as RFID design data, material data, location data, and supplies data. A fter selecti ng and retriev ing by different needs, selected data i nput to BIM model base to run out a result The result imply at BIM decision making process to practice the decision. The final solution as finished RFID data save s back to R FID database for future decision making using.
107 Figure 57. RFID u sing D ata flow for BIM /RFID Framework decision making process U sing RFID for S teel S tructure D esign Using RFID technology for construction parts marking and tracking ha s been widely accepted. The use of RFID as a series number is one of the basic functions of RFID. RFID can be used as a standard measurement to identify steel design components. For example, the steel grades on BS5959 (AISC) for steel tension design have specific design requirement s based on different members thickness and temperature. When design ed at a structure s external temperature to minimum 15C degree, the incorporated RFID tags will automatic ally show that the maximum thickness for a Grade 50A Beam is 10mm (Hayward 1989) If a user entered this data in the Design Decision S upport system (DDS) and RFID tags, when erect ing members at a jobsite, it would give a warning when somebody installs a wrong piece, even if that piece fits to be c onnect ed with other parts. RFID can be coordinate d with the standard design data so th at designers can easily find the right piece from a data pool. In another words, users can read the information even from RFID RFID Using DATA Layers BIM Decision Making Process BIM Model Base DDS MDS SDS JDS RFID Design Ft RFID Material Ft RDID Location RFID Supplies 3D Mode l CNC Model Supply Chain Planning and Scheduling BIM Project Finished DATA
108 series number, for example, RFID number BS4360WR50 W12x36 is a BS 4360 Grade, weather resistant high tensile wide range steel 12 inch wide and 36 pounds weight steel member. For the 10mm Grade 50A Beam example as described above, the next time if all conditions are the same, if a user gives the or der to the DDS, the fitted RFID members will be selected. The selected item fits to the required field beams, columns and girders. Then the steel members for a wall, a floor and a building will be automatically verified by using RFID tags on the members a nd the system functions of the BIM /RFID decision support system. RFID using data layers can be used as design components to create a 3D model. How the RFID Works in a Steel Structure The details about structur al steel components are stored in the RFID database. Depending on the technology limitation and chip cost, the memory in the chip can reach 256 kb currently T his memory can be writ t e n to with only minor informati on to show steel members ID s and location information. But users can still retrieve ot her information from RFID system when us ing the wireless tech nology and ID coding system ( For details see Figure 5 8) The RFID system us es a Universal Product Code (UPC) which was developed for grocer ies from mid 1970s. The UPC code is the same coding like barcode system which is still widely used today. Currently, the RFID system had been installed to expedite non line of sight data capture using RF to read the electronic product code (EPC) on RFID tags. The RF domains such as cellular telephony and wirel ess LANs are accustomed to working at much higher power levels. There are more host processing capabilities in cell phones than are present in tiny RFID tags as of the first EPC GenII/ISO 18000 6c RFID infrastructure (free up the 860960 MHz UHF spectrum, similar to IEEE 802.11 WiFi protocols for unlicensed RF data communications ) (Miles 2008)
109 Figure 58. RFID data r eading in s ite BIM /RFID Framework Layout An RFID system is an integrated collection of components that implement s an RFID solution. An RFID system consists of the following components from an endto end perspective. Tag : This is a mandatory component of any RFID system. Reader : This is also a mandatory component. Reader antenna : This is another mandatory component. Some current readers available today have built in antennas. Controller : This is a mandatory component. However, most of the new generation readers have this component built into them. Sensor, actuator, and annunciate : these optiona l components are needed for external input and output of the system. Host and software system : Theoretically, an RFID system can function independently without this component. Practically, an RFID system is close to worthlessness without this component. Co mmunication infrastructure : This mandatory component is a collection of both wired and wireless network and serial connection infrastructure needed to connect the previously listed components together to effectively communicate with each other. (Hu 2008) A schematic diagram of an RFID system application strategy is shown in Figure 59. The concept of the RFID application strategy is as follows: (1) Place a transponder (a microchip with an antenna) on an item (2) U se a reader (a device with one or more antennas) to read data off of RFID Tag RFID Database Wireless RFID Reader Input Output Output Input
110 the microchip using radio waves. (3) The reader passes the information to different computer systems, so that the data can be used to create business value. In steel structure construction, the current main purpose for using RFID is to track a steel member s progress and location. In this research, RFID can be regarded as the project information carrier. A passive RFID tag and low radio wave frequency RFID technology is enough for the current use. Fabrication Erection Prefabrication Delivery RFID created & Design information assigned a Tag for a steel member, use RFID as design components Assigned RFID members at gate, RFID data transfer to GC and site office, GPS tracking, RFID data update at site gate RFID data input to Tag and attached to steel components, RFID data update RFID+GPS locating members, RFID data read and send to site 4D BIM model, RFID data update, RFID assistant BIM decision making RFID database center Figure 59. RFID a pplication paths The LF (Low Frequency) RFID, such as 125 KHZ tags, and compact flash (CF) slot type readers can be chosen as the basic readers to be utilized together with personal digital assistants (PDA). The PDA also has networking functionality so that the PDA r eaders used will then be connected to a personal computer (PC). The stationary readers will be installed at the gate of a construction site. (see Figure 45) The RFID tags have to be attached to frame members by using magnet or glue after fabrication and painting with a rubber shell around the surface. Another use of tag may use clip cards for invoices to track the delivery and receipts of structure steel members. (Chin 2008)
111 T he RFID data implementation can be divided into four steps: (1) design and pre fab, (2) fabrication, (3) delivery, and (4) site erection. Figure 510 shows the details of the steps. The explanation of the steps is as follows Step 1. Design and Prefab The design information for RFID tags begin from the drawing process. The steel IDs are generated from the architectural and engineer ing drawings. The architect or engineer may create a qualified RFID system in the specification for the project. The drawing data are sent to the contractor, who then sends them to the fabricator. After the fabricator has received the project information, the fabricator may select one type of RFID to submit to the contractor. The RFID tags, antenna, and readers requirements information should conform to the specification manual for the construction project. After the architect approves the RFID submittal (sent from the contractor), the sample will be sent back to the contractor. After the receipt of the approval, the fabricator will submit orders to RFID suppliers. At the same time, steel will be prepared fo r the fabricators shop works. In this step, the data are transferred from the architect and engineer to the fabricator but may or may not come with the RFID information A fabricator may work as an erector or a separate erector is hired as a subcontracto r in the installation process. The data type in this step is 3D project model. The software options include: AutoCAD, ArchiCAD, Revit Structure, or Tekla Step 2. Fabrication In this step, the fabricator needs to perform the prefab rication work in a shop i n accordance with the shop drawings. The same RFID may be used in the base plate, which is shipped to the jobsite before foundation concrete has been poured. The RFID tags can be attached on the steel components when the members are ready to be delivered.
112 Architect Engineer General Contractor Subcontractor (Fabricator) Subcontractor (Erector) Subcontractor (Crane) Subcontractor (MEP) RFID BIM Fabrication Delivery Erection Design Drawing RFID information Implementation of Steel Erection Approval drawing and Code Shop Drawing and Code giving Design Drawing Award Project Award Steel Project Award for Erection Received Retal Order Award MEP Receive Drawing and Code Manufacturing Process Cutting & Assembling RFID Tag On Rust Proof and Pinting Inspection with RFID RFID System Submittal and Approval Scaning RFID out and Shipping GPS Tracking Build 3D Model RFID Code information Shop Drawing with Component ID Generating/Register Component ID Register Assembled Component ID Transporting With RFID Tracking At Gate Scan RFID Tags Scan RFID Tags Scan RFID Tags Assign a RFID Invoice Tags Crane Hoisting On Site & Inspection BIM with RFID RFID with Member's Information in Real Time 4D BIM Database Erection Plan Crane Plan MEP Plan Erection Order 1 RFID Retrieving Erection Information Crane on Site 1 Hoisting Order RFID Information Retrieving RFID Tags Scaning Upload and Installation Column at Sequence 1 RFID and GPS Aid Located Member AnchorRods and Base Plate Located Si Upload and Installation Beams at Sequence 1 Members Connection (Bolt and Weld) RFID Retieving Connection Information Hoisting Column and Beams as Order MEP up at Sequence 1 Bracing and Lateral Stability Slab on Sequence 1 Inspection and Roofing Sequence 2,3,4,5,6... Crane on Site 2 Hoisting Order Hoisting Column and Beams as Order MEP Up at Sequence 2,3,4,5,6... Erection Order 2 Upload and Insttallation Column Upload and Installation Beams at Sequence 2 Members Connection2 (Bolt and Weld) Bracing and Lateral 2 Stability Slab on Sequence 2 Inspection and RFID Information RFID Tags Scaning Scan RFID Tags Scan RFID Tags Scan RFID Tags RFID Retrieving Erection Information Inspection .. Fire Proofing Figure 510. RFID data i mplementation f lowchart
113 Before a RFID tag is attached to a steel component, RFID tags have members ID and other information in its memory. Finished steel members are placed in the fabricators storage place or warehouse with RFID tag s on them. A fter the RFID tag is attached to the steel c omponent, the tag and the member will be inseparable. In this step, the steel component information is entered into the RFID, scanned in the storage, and tracked by a system. The tracking process covers the whole project construction duration. The tracking on RFID data might be longer than project duration if users need to track the building facility utilizations and energy saving s A fabricator begins to track RFID after fabrication. The information stored in the RFID tag may be just a seria l number or code How much information can be stored in the RFID chip depends on its memory size. In this study, it is assumed that low memory tags are used because they are more economical As a result, most of the information will be stored in the computer system of the BIM /RFID Framework and the information is retrieved and shared via PDA. The data type in this step is CIS/2 and RFID. The software used in this step may include: AutoCAD, Vico, NavisWorks, Revit, Tekla, or CIS. Some fabricators use an Automatic Manufacture System (AMS) to help their shops in fast tracking, which means that they can fabricate steel while the steel design is still in process. Computer numerical control (CNC) is one of the AMS which can cut steel parts just after the detailing of the 3D model had been created. The fabricator usually has a large amount of drawings to deal with. Shop drawings normally cost a lot of money to detail, copy and store. The time spent on blueprints transactions among owner, archi tects and engineers is huge and is a potential factor for project delay. BIM design, AMS, and CNC make these transactions more efficient and consum e less time.
114 Step 3. Delivery When the delivery time has arrived, the steel components are sent out from stor age. The electronic readers at the warehouse gate will scan the RFID tag automatically and update the information in the storage database of the computer system. The truck driver will have the steel information uploaded to his PDA. The invoice tags with RF ID information can also be stored in the truck drivers PDA. A GPS system can track the truck and evaluate the arrival time. The data type in this step is GPS and RFID. The software may involve: AutoCAD, ArchiCAD, Tekla Vela System, or Revit. Step 4. Erection The steel components will be scanned when the delivery trucks enter the jobsite gate. Then system will know which steel components have arrived, where they are unloaded and stored, and when they are going to be installed in the erection sequence. Upon delivery to the job site, the fabricated steel will be unloaded and placed on wood (or steel) blocking. The blocking allows chokers to be attached to each member for subsequent hoisting and erection. The site installation manager checks the erection plan and gives orders to the crane operator and foreman. At this time, the BIM 3D model has been buil t up in the computer and will be waiting for component processing. The field foreman scans the RFID tags into the system. For example, the crane used for a project may be a 100 ton crawler mounted crane with a 160foot boom and a 40 foot jib. The boom is the main projecting structure of the crane and the jib is the smaller structure attached to the boom. There are many configurations and sizes of cranes availab le. Cranes are selected on the basis of cost, availability, speed, reach, and capacity (AISC 2008).
115 A special column hoisting device is used in the project. It has a release attached to a rope to facilitate its detachment from a column. After the column is secured with the required bolts, an ironworker starts the release directly from the ground to disengage the hoisting cable. When the first column is hoisted into position, using ladders, ironworkers temporarily bolt the column. Prior to erection, the inst aller must consider column stability in accordance with safety standards and the AISC Code of Standard Practice. The installer may read the RFID tag and check the connection information before bolt connection. The information retrieved for the Erector is t he components RFID number and location, connection methods, bolt size and type, and welding type Installers can read from the ir PDA about the information. Every time when scanning the finished component, the RFID data will be transferred to the real tim e 4D BIM /RFID Framework in the office computer through wireless technology. The steel component in the model will change to a finished color, for example: from red to green (assuming red is the color of the not installed component). After the erecti on plan finishes, the model color will be darker than the previous green, for example: from green to brown. Another way to implement this progress is to remove the RFID tag right before the member has been lifted to its location. All t he removed tags are submitted to site office and scanned by PDA reader to change the status es of the corresponding members to show erected. With the RFID and PDA, all participants from the designer s the engineer s, the fabricator s, and to the installation manager s of this p roject can read the progress of jobsite. Data type in this step is RFID and GPS. The software involved may include Tekla, Vela system, AutoCAD, ArchiCAD, Vico and Navisworks The main uses for RFID data in real time 4D BIM /RFID Fr amework is in project planning and scheduling, cost analysis, reporting, inventory management, and erection sequence
116 management. RFID data is also used for data sharing and transfer purposes in drawing, inventory, and supply chain functions. Among these functions, 4D schedule and planning is the core of the real time 4D BIM model. RFID tags help in tracking the structural members progress through erection. The RFID data is used to record the status of each member from manufacturing to erection at the cons truction site. The RFID data for each member are collected by using RFID readers and then the erection status is tracked in the real time 4D BIM model. This method gives an almost instantaneous status report of the progress of the erection plan to site and project managers or controllers. RFID data can help with inventory management. For example, it could help in arranging just in time jobsite delivery. The RFID tracking system gives a record of the corresponding component information whenever it has passe d the jobsite gate or each time it is scanned by readers. In this case, the supplier can check inventory and issue purchase order s on time. RFID erection data can help cost control when the optimal operation solution is sought. It could help convert a site delivery system into a just ontime zero storage plan. The steel component can be installed right after it arrives at the jobsite. This will decrease cost by saving crane operation time, cutting schedule time, and saving storage space. Another benefit of RFID data is that they can help with the cost control process in the crane and erection sequence plan. The crane operator can use RFID data to adjust project progress. RFID data can help make real time changes on drawings. RFID data can be used to manage the administration of new drawings and create a record for any changes. Shop drawings can be adjusted for member connection problems and supply problems. RFID data can show the change and record the new data. R FID data helps sequencing project management a nd
117 controlling the progress of work by providing advanced notices. For example, consider a project, where structural steel works were repeated in 5 day cycles for each floor. During detailing, the steel frame was divided into 6 sequences as illustrated on the erection drawing (see Figure 6 14) Sequences represent the order in which a zone or section of the frame will be erected. RFID data used to track actual erection could be used to improve the efficiency of the erection process in the sequence plan. Pr oper planning of erection of the sequences allows parallel construction operations to take place. For example, while the erection crew erected sequence 2, the decking crew placed metal deck at the previously placed sequence 1. In this way, the deck placed at sequence 1 formed a work platform and reduced the fall distance when the steel contractor erected sequence 3 which was above sequence 1 (AISC 2005). At the same time, RFID data is used to show the details of the members in the sequence of work process. This helps the supervisor in adjusting the work tasks for the efficiency and optimization of different sequences. RFID data can also be used to help the steel erection foremen and connectors by providing all information to them. The RFID tag contains data which can be read by erection foremen or connectors PDA and correlative information can be retrieved from RFID system database or from preinstalled database using PDA. The worker can download the needed information right away. The 4D BIM/RFID Framework and the simulation of the erection schedule are performed based on the sequence order presented in each 4D model. In addition, the color of each 4D CAD model steel member changes depending on the progress information collected through RFID technology.
118 The overall progress status as well as the member progress is also identified. The application of RFID in the structural steel work enables more accurate logistics and progress management. The application leads to the reduction of risks, including materi al loss and schedule overrun, by identifying production and delivery information in advance and by monitoring the erection process on a steel member unit basis (Chin 2008). T he implementation of RFID technology in construction has great potential to help c ontractors and subcontractors in the fabrication and erection of steel structures. The RFID data can help the real time 4D BIM/RFID Framework to be more efficient in modeling the process and to save time and money. An Example of RFID Works in Steel Member RFID techn ology currently is slowly being accepted by steel fabricators and erectors. A single use for tracking the member location is not worth the use of an expensive RFID system. The barcode system has been used by many steel companies since end of last century W hat the RFID can show to AEC and site personnel ? Is it worth to have RFID to use in jobsite? Here is a case study example to resolve these questions. In the Figure 511 (a) (d) show how a column changes in a simulation of a multiple floo r structur al steel 4D model. Figure 511 (a ) shows the column simulation in Sequence 1. The column RFID # C10A0301 in this 3D image has not been erected. T he information the RFID Tag of Column #C10A0301 includes : Steel features Mill, Manufacture, Inspector, Storage, Delivery and Site location IDs and Dates. If the memory is big enough, other information such as connection methods, welding methods, and so on may also be included Figure 511 (b) shows columns that have been built up. The s ame column ha s been erected but not connected. At this point more information will be added to the RFID database installation date, crane operator, superintendent, erector, etc. The RFID tag currently is not
119 available for reenter ing information because of the costs involve d. I nformation is input to the RFID database system through wireless PDA reader or manual typing. This task was also performed at Sequence 1. Figure 511. 4D BIM M odel s hows a c olumn with RFID c hanges (Revit 2008) Figure 511 (c) shows the work at Sequence 2 and 3. The column #C10A0301 was connected with beams #B20A0301 and #B20B0301. The updated information added on to this sequence is the connected beam information, connected inspection information, erector and connector, c rane and operator, safety issue, date and location GPS points, maintenance require ment, bol t ing and welding methods, bolt size and specification, etc. The RFID Database system is updated with each steel structure components situation. It should be inspect ed in detail by the foreman using RFID reader to check the components RFID t ags and connectin g pieces. B10A0301 B10A0301 B10A0301 C 10A0301 C 10A0301 B1 0A0301 B10A0301 B10A0301 B10A0301 B10A0301 B10A0301 B10A0301 (a) (b) (c) (d)
120 Figure 511 (d) shows the building finished with the outside wall in place The Column # C10A0301 now has all its connection information updated includi ng its attach ment to the walls and roof trusses, Girders, Bracing, Plate and Rod. Every connect ed members and its information may be found by checking its RFID tag and log into t he RFID database system in the BIM/RFID Framework The construction proje cts have been completed and t he RFID information of Structure steel components is updated on time. This RFID information will be kep t in the building facility model to maintain the building life c ycle situation. In this way, the building components can be monitor ed piece by piece by using RFID records and maintaining the system. T here are some items that RFID tags cannot be attached to For e xample, small plate pieces bolts and welding material, etc. How does RFID technology work for them? Although these s mall pieces cannot have tags attached to them they still need RFID number s to identify them. T heir features and connecting information would be read from the RFID database system. Small piece members can name RFID by group or with attached beam or column. Even piece too small to attach a RFID tag, it is still necessary to assign a RFID code so that RFID can represent every member The RFI (Request for Information) and RFC (Request for Change Order) can be stored in RFID database too. There are two ways to handle RFI or RFC questions One way is to solve the RFI and RFC all manually; the other way is to use computer system to help solve the problems. Historical RFI and RFC documents are saved in RFID database so that BIM decision model can find options for R FI or RFC from similar cases. Using the RFID database and the BIM /RFID Framework to find an answer and to request the manager s approval usually is better than the manual method.
121 In th e case, the connector from RFID checking result of design beam #B10A3102 has a loading warning when use A43 with double bolts connecting with column #C10A3101. After the user check s the RFID database and has found the reason because the wrong sides installation for #C10A3101. A shear plate welded on #C10A 3101 should face outside but is installed facing inside. O utside bol ted connection i s not strong enough to hold a canopy attach ment The user writes a RFI from their PDA system and scan s connected beam RFID tag and enter s the plate RFID. The system uses it s wireless connection to send the RFI to the site BIM /RFID Framework The BIM /RFID Framework works for sending the RFI and data searching immediately There are three methods to treat this problem from the RFID database. (a) To rei nstall the column. (b) T o welding another shear plate on another side in the same place. (c) Redesign the bold connection and chang ing to stronger bolts. At the same time, the BIM/RFID Framework ha s cost analysis and building code search capabilities The Project Manager receive s the three options and a cost analysis (by checking RFID database found the cost data for plate and bolts) of the options for the RFI and RFC request. After a few minutes the Project Manager decides to take the Chan ge Order for the option 2. After an RFID search from the project BIM /RFID Framework there is one of the required plate s on site which is to be use d for the next days job. Then, a parts order send to supplier and a RFID system showed up the plate loc ation. This total change order used 20 minutes from the site problem to sending out a purchase order (P.O.). Figure 512 shows the different RFI flow between tradition method and RFID database method. In the tradition al method, t he RFI need s to be sending to Superintendent, PM, and AEC, then they go to find the answer and they issue a P.O. Usually RFI take at least two days for the process. The BIM /RFID decision making model significantly short ens the process, in the system,
122 the AEC, Superintendent (SI) an d PM knows about the RFI and followed options at about the same time. By using RFID and 4D CAD technologies, a real project in Kor ea saved 17 percent of project progressing time and 72 percent of sto ck yards (Chin 2008) It shows RFID can be used in a BIM model with 4D tools. RFID Cost Building Code LRFD Code RFID Database BIM/RFID Framework RFID Foreman Superviso PM AEC Site RFI Answer & P.O SI&PM AEC P.O. JDS SDS MDS DDS Decision Tree Simulation Calculations Experimental Analysis Output Input TESTING DATA BASE MODEL BASE Options Tradition RFID METHODS Figure 512. Tradition RFI or RFC versus RFID jobsite flowchart If put every items with RFID to mark the change, t he BIM /RFID Framework would easily create an emergency reflection system to deal with jobsite uncertainty incidents For example, a lost of Beam B01A0310 as a steel s tructure item may bring change s I in the plans for crane CR01A5 Cost E 01A increase and OSHA Regulation 29 CR1976 warn ing s.
123 CHAPTER 6 CASE STUDY In this chapter, a n e xample will be used to show the concept and logic of the BIM /RFID Framework A multi story project example will be used in this chapter. Because the research is focused on steel structure construction, the multi story project is built up digitally by using Autodesk Revit for 3D modeling, the Suretrak for scheduling. In specific, this chapter also uses a steel component example to show the steel component s status, specifications, and locations on the drawings and on the job site. Case S tudy OCW Building The OCW building is a f our story building located in Little Rock, Arkansas. The OCW building is used as a classroom/office building for the College of Engineering. The building consists of a steel structure. It uses brick as exterior material. It has an auditorium and a bridge to connect the existing neighbor ing buildings to it. The bridge connects two buildings at their second floors. The estimated budget of the OCW building is approximate $10 Million The project is expected to be finis hed in 17 months. The construction management process of a project involves making choices to find out the optimized solutions for problems or situations emerging during the project. Each member of the project team will make their own choices to satisfy b oth the requirements of the project and the best benefits of its own company. In the decisionmaking process, an individual should collect all the project related information as that they can. The decisionmaking process in construction project is a compl ex task. In order to simplify the process and provide assistance in the decision making process, the proposed system us es Building Information Modeling (BIM) and decision making technologies in the construction management process. M orphological analysis or General Morphological
124 Analysis is used in the proposed system. Morphological analysis or General Morphological Analysis can be used to explore all the possible solutions to a multi dimensional, non quantified complex problem As a problem structuring and problem solving technique, morphological analysis was designed for multi dimensional, non quantifiable problems where causal modeling and simulation to not function well or at all. By reducing the number of possible solutions through the elimination of the illogical solution combinations in a grid box, the proposed system will help users to reach t he optimized solution. The following example shows how a construction company can use the proposed system to handle complicated construction situations or probl ems. BL Company was called Bad Luck by workers after being awarded the contract of the OCW building. From the beginning of the project, everything was gettin g worse and out of control. The project team has not yet made any firm decision on any of the problems in this project. Various impact factors and hard to predict results contribute to the hesitation and discrepancy in the decisionmaking of the highlevel managers. The VP of Operation and the appointed project manager were just fired because they were responsible for the companys benefits lost. The Board s chair of owner, Mr. Oregon, had called them three times about the project delay s In this case, the company wants to get immediate help from a consulting firm which has BIM tools that can be us ed for this big steel structure project. ABC consulting signed a BIM contract with the GC which was approved by owner and architect. It uses BIM and DIS (Decisio n Information System) in this project based on its duration and other situations. Figure 61 shows the differences between a tradition al steel structure project process and the project work flow using BIM methods It also shows the
125 progress change s and dur ation change s In tradition al process, the design parts may finish earlier than the BIM. Us ing BIM methods can save time in the case of a request for information ( RFI ), transmittals delay change orders, and jobsite mistakes. Design RFIDSN: B10A0301 Manufacture and Fabrication Delivery Erection Inspection Detailing Construction Begin BIM Contract Model Outline Simulation and Revises Delivery Field BIM Control Files Information Transaction Manufacture and Fabrication AEC Design Approved All information and Documents Collecting RFI&RFC All Document Close Facility Mangement Inspection BIM RFI & RFC System Beam 10A0301 Designer Febricator Engineer Deliver MEP Subcontractor Inspector BIM Team1 Febricator Field Office (Erector&MEP Subcontractor) Inspector Erector Contractor Bid Designer Deliver Contractor Facilities BIM Team 2 BIM Team 3 BIM Center Tradition BIM Current Field office Field Office Punch List Engineer Figure 61. The BIM/RFID and tradition al methods process for a steel structure project RFID is included in this BIM project and it impacts the entire project. It makes it more convenient in managing projects, especially when tracking project process and erection connect ion details. In this project, the drawing design had been finished. For the ABC firm the first step is to transfer the 2D drawings to a BIM /RFID 3D model. The transfer process involves the following steps : Step 1 : Transfer a 2D CAD drawing to a 3D BIM /RFID. The Architecture firm has a CD with 2D CAD file s and drawing documents. After some considerations about this project, the ABC project manager has decide d to use 2D Revit Navisworks applications with a 4D BIM deployment later. Figure 6 2 explains the architecture of the transfer process of project files. The drawing format from 2D to a 4D drawing, and members are assigned with RFID each. Other document s come with RFID members also. RFID use as activity label can displ a y the project schedule as well.
126 Figure 62. Project files transfer architecture Step 2 : Use RFID to identify each steel member in project and input RFID to BIM /RFID framework RFID is used to identify each steel member so that the follow up digital file has a connection code for combination. Also the files using RFID can be easily tracked with location and progre ss. The RFID number can be normal ly used number or a specially created numer ical code for a single project. The AISC ha s a building marking system for steel member identification which can also be used in RFID tracking Step 3 : M ake a new project schedule The project schedule in this example us es Microsoft Project as the scheduling software. One file format of Microsoft Project is MPX. The project schedule shortens the way to transfer a BIM project into a Navisworks format file type because Navisworks can open MPX type file. Step 4 : Simulation and testing RFID and 4D BIM tools Before using RFID as a member identification tool, the steel member s number is only a number which means it does not carry any practical use except a way to distinguish one item f rom others. After using RFID to identif y steel members, the numbers enriched their meanings and carry lots of information about building process, connections, and more. Using RFID to 2D (CAD or DWF) Revit 3D (RVT) Navisworks 4D (NWC) RFID Steel Memb er RFID Project Scheduling Drawing Documents Planning
127 simulate the project progress makes the Architect, Engineer and contract or ( AEC) able to track the details of structure steel erection. With the aid of simulation, users can forecast problems to avoid possible adverse situations. Using RFID in 4D BIM can help users build an advanced scheduling track. The scheduling track can h elp them see the details in the schedule. They can use the scheduling track to monitor and control changes and buffers in advance. The scheduling track also makes it possible to revise the project buffers or request an RFI in advance. Step 5 : Use the BIM / RFID framework to control the project. After the simulation of the project and tracking the project schedule, ABC firm rearranges the schedule buffer in order to ca t ch up on the project delay. Then it became time to set up a site office to control th e project. In this case study, the BIM team needs to develop the optimal erection plan for the delayed project. This plan should decrease the duration of the project and meet the technology, cost and safety requirements as well. To use the BIM/RFID decisio n making model, four major questions need to be answered: First is determining the optimal erection sequence. The sequence needs to satisfy two parts: the steel components erection order and the suitable sequence arrangement. Seconds is to establish the c rane plan. The crane plan needs to satisfy two parts: crane numbers and optimal operation control. Third is to establish the optimal delivery plan. This plan should have the optimal driving route and optimal timing. Fourth is to establish the safety plan. The reason to list the safety plan as a major question is because any OSHA violation would directly cause a serious project delay and cost increase. Figure 63 shows the BIM /RFID F ramework with the details for the erection plan. It shows the BIM model us ing RFID for an optimal erection plan. In the Erection Order process, the
128 sequence plan and steel member order for hoisting up is the main consideration. The s equence plan includes sequence arrangement and job arrangement. Sequence arrangement needs to thi nk about how to arrange the sequence for a safe and effective work space so that scheduling is optimized and no barri er between sub works can be achieved. For example, the RFID database has all the steel components information The weight s, sizes and othe r features of steel members are considered as factors for developing the erection plan. The locations and connections information of steel members need to be considered to make an optimal plan. When inputting the data in the BIM /RFID Framework the model will run a test for possible erection sequence and order. After simulating the process, if the result fits cost, technology, and safety requirements, multiple options may be suggested The next step is to output these options to BIM /RFID decision support systems such as DDS and JDS. After comparing the results, the optimal answer will be selected and all project information such as cost estimating, scheduling, and other subcontractor work change will also be calculated. RFID data layers in this step work a s a smart coding to corporate the model. Job arrangement focuses on job planning and work force arrangement. A ll these tasks need to be simulated by using 4D BIM /RFID and system integration methods such as an optimal manufacturing system. RFID as a digital information carrier has a coding system and a number. RFID is the basic condition for autom at ion control which can go through the decision s teps of BIM/ RFID Framework In this stage a JDS (Jobsite Decision System) may be used more than other systems.
129 Erection Plan Crane Plan Safety Plan Delivery Plan Human Safety Erection Order Equipment Safety Member Order Sequence Plan Crane Number Operation Plan Timing Optimal Road Job Arrange Sequence Arrange Optimal Order RFID Arrange RFID Distance RFID Equipment RFID BIM On-time RFID Location GPS Location BIM Zoning RFID 4D BIM Simulation BIM/RFID Framework Figure 63. BIM /RFID Framework for optimal erection p lan
130 How RFID C reating an E rection O rder Figure 64 is the process of RFID creating an optim al erection order. From the RFID database, each member s features and factors can be listing and grouped by sequence, floor location, bearing factor, size factor, etc. These items are ranked by different priority from high to low. T hen a basic erection ord er is build up. In real project, the project sources are changes and uncertain sometimes, such as worker numbers, delivery condition, equipment condition, utility available, and other uncertainty changes. Figure 64. Detail of RFID database creating erection order plan When sources varied, the erection order and project schedule should follow the changes. Using RFID coding system, the order schedule has to run for changed factors as of priorities to create a new erection order. For example, the first floor and loading column is the High priority, adjustable beams is median priority when the attached members is the low priority. Retrieval from RFID Member Database Sequence Floor Bearing Size RFID Source Available Worker Delivery Equipment Utility Uncertaint Input to BIM Decision Model RFID Measured Priority of Members New RFID Erection Orders Schedule High Priority Less high M edian Priority Low Priority RFID Measured Priority of Member s RFID Erection Orders Schedule High Priority Less high M edian Priority Low Priority Input to BIM Testing Output to 4D BIM Simulation Output to 4D BIM Simulation Function Block
131 In this progress, RFID as a smart coding system to check and to match building code and erection fact ors from RFID database. The 4D BIM /RFID Framework simulation function run for the result of erection order to verify its rationality. RFID and 4D S imulation for C rane P lan Crane Plan includes two things: operation plan and crane numbers. Operation order i s associated with member order of erection order The number of cranes depends on the calculation of the work load, cost, and schedule. Similar to the Erection Order, RFID is necessary for system to simulate in a 4D BIM environment. How many cranes are nee ded for the project depends on a detailed calculation and simulation. This question can be resolved by using the BIM decision making model. Because the crane erection order plans same as members erection plans The process of crane erection order plan is same as Figure 6 4. The source used to design the number and crane location from RFID database. Figure 65 is the RFID creating of crane plan processing. The crane features are listed as a priority sequence. They can use RFID retrieved from RFID database. RFID and BIM C ontrolling D elivery O n time Delivery Plan includes road selection and timing for jobsite needs. T he major function for RFID is tracking and identification. RFID system with GPS system is used in delivery tracking and supply chain for years. Its advanced functions have been highly praised. RFID database with BIM decision making system can help to develop a better delivery plan as well. The details will be discussed in the following ontime delivery case study. Figure 6 6 is the RFID creating o f delivery BIM ontime. The function block in it is a Delivery Algorithm block. RFID database and project sources a re discrete data, the function block make them logically and orderly.
132 Figure 65. Detail of RFID creating a crane plan Figure 66. Detail of RFID creating a delivery BIM on time plan Retrieval from RFID Database Type Height L RFD Cost Retrieval from RFID Source Available Worker Delivery Conditions Utility Uncertainty Input to BIM Decision Model RFID Measured Priority of Members New RFID Crane Plan High Priority Less hi gh M edian Priority Low Priority RFID Measured Priority of Members RFID Crane Plan High Priority Less high M edian Priority Low Priority Input to BIM Testing Output to 4D BIM Simulation Output to 4D BIM Simulation Range Lifts Number RFID Database RFID Database Retrieval Members Features and Priority Rule Input RFID BIM On time Delivery Algorithm Erection Order Site Data Crane Plan Truck Available Output Members Delivery Plan Function Block RFID Loc ation GPS Location Members Source Available Optimal Delivery Plan Circle Retrieval Function Block
133 A construction project whether it's an office building, factory, bridge, airport or other facility is a highly coordinated, complex operation that must run according to schedule. Any delay in a construction schedule can be costly to the contractor in terms of salaries, leased equipment and maintaining security at a job site for longer than was budgeted. Figure 67 shows RFID Data flow during delivery process RFID tagged members loaded in the truck with GPS device The RFID system sends members information to GPS system, then through GPS system and wireless transferring their real time location to RFID database. The BIM 4D model can simulation an erection order depends on the esti mating steel arriving time. GPS and RFID develop a wireless position tracking system, make on time delivery possible. Figure 67. RFID data flow during delivery RFID BIM Zoning The Safety plan includes equipment and human s afety components. RFID and GPS have been used to control work space and riskily distance warning. RFID safety warning equipment for workers has been designed to be w orn on a hardhat and helmet too. I t can protect workers from fall and other accidents. Fig ure 68 is the detail RFID creating a BIM zoning for safety plan. In this data circle, RFID safety database for equipment safety and site work safety are separated selected. Truck Location GPS Devices RFID Members RF ID Database Wireless BIM 4D Model (NavisWorks, Vico) Site Order
134 The items for site work safety data are different than items using at equipment safety. For example, the type in site worker safety is as of job type when in equipment safety is equipment type. In site worker safety, the height is OSHA jobsite length and height requirement. In the equipment safety, the range is equipment working range and height features. As same as erection and delivery plan, the safety plan is adjusted with source available also. When project has source shortage or other uncertainty accidents, the new RFID data will run the BIM zoning model again to make an optimal s afety plan to cover the change. Safety algorithm is a computer numerical program which uses smart coding and artificial intelligent techniques to make an optimal plan for given resource. The RFID database should include OSHA regulations, building code, equipment operation menu, and so on. The zoning control also needs network and security cameras monitory systems. A functional network can serve a good RFID data transaction so that BIM tools working accurately and effectively Figure 69 shows RFID in BIM zoning safety control system. A designed RFID location system has readers sited on required position s Special RFID tags were attached on equipment and workers hardhat or helmets. In an intranet environment, R F ID location system can arrange a distance for safety control and locat ing riskily locations such as hoisting area, flammability area fall ing zone, and heavy equipment path, then making a warning system for danger movement or possible safety violation. For the worker with RFID hardhat on if he entered any of these danger locations may receive an alert or a reflecting alarm. Also it may have different frequencies to zoning the safety.
135 Figure 68. Detail of RFID creating BIM zoning for safety plan Figure 69. Sketch map of BIM zoning safety control Retrieval Equipment Safety Data Function Block Input BIM Zoning Map Safety Algorithm Network Control RFID Function Distance Sequence Data Output Site Worker Safety Data RFID Safety Zoning Plan RFID Safety Database Type Height Gate Helmet Sequence Operation RFID Safety Database Type Range Bearing Risk Sequence Operation Retrieval Optimal Safety Plan Circle Members Source Available Retr ieval Retrieval BIM/RFID Zoning Decision Making Wireless Office Transport Man Work Z one B Work Z one A Crane Zone RFID Location System
136 Case Study S Steel Company Background The following is the background description of this case study: S Steel Company is one of the largest steel contractors in the US. It has 2000 Employees in its L ittle R ock, Arkansas division. Its t hree main fabrication shops are located on a total of about 60 Acres land. Figure 610 shows S Steel Companys organization al char t. Among steel contractors, S Steel Company has the most advanced techn ology programs and training resources. They have been listed as top 5 steel contractor of the year for more than 10 years Task and Plan The president of S Steel Company went to the AISC conference and learned some knowledge about BIM. He has a very strong feeling that BIM can do excellent work for their projects and can help in cost savings. After coming back to his office, he holds a meeting with managers and made a report on BIM re search and a feasibility study. The first thing that needs to be done is to find out the easiest way to rearrange their current resource s to deal with the new BIM task. Then they have to check whether current BIM technology is adequate to support their jobs. This task is assigned to their techni cal support department which is associated with Dr. Z from the Building Construction Department at University of Arkansas.. Here are the questions they have to find answers to: What are the right BIM tools for the ir work? What kind of organizational frame change is needed to fit this BIM model? What is the workflow that BIM will bring to them? What is the budget for this work? What improvement does the BIM technique contribute to their jobs? What are the benefits of this change?
137 President Accounting Operation President Human Resource Shop Manager Sale Welding Shop Supervisor Project Manager Erection 2 Estimating 2 Design & Engineer Technique Bridge Manager Shop Supervisor Shop Supervisor Cutting Delivery Material Paiting Parts & Templet Storage Erection Estimating Detailing Project C Project B Project A Figure 610. S Steel Company organization structure chart
138 After the review of the company s existing software and equipment, they know they have AutoCAD as main design software and SDS/2 as detailing software; MS Project 2007 as project scheduling software: MS Excel as estimating take off software, and other software used at their shops. A fully ranged (Computer Numerical Control) automated fabrication equipment is used to operate steel plate cutting and hole drilling. Shipping me thods include common carrier, Union Pacific Railroad, air cargo, and river barge shipment. Re organization for a BIM Model Base Company Structure The first challenge is to reform the firms organizational structure. The firm has over 30 years of history. T he risk of change to the firms organization structure is obvious A tough conflict would damage the whole program. So, after meeting with department managers and company board member s the result of discussion is a compromise that the company organization would be changed as little as needed so that it can support a BIM model. Also, the change plan should maxim ize the us e of current equipment and software. After research on effective ness and compatibility, they decided to use an organization structure char t with BIM function combination as shown in F igure 611. In this design of the organization, one BIM manager leading functional BIM department is under the Operations President and the s a me level with construction PM and bridge PM. His duty include s : Res ponsib i l ity for all BIM related work, including but not limited to BIM models, shop work continuity with BIM control tools, and on time BIM support. Associate with general contractor project manager and their architects and engineer s to deal with each project RFI and RFC problems. Responsible for BIM team works arrangement and assignments. Verif ication of BIM design engineering work, and estimating result s Control techni cal support and BIM networking safety.
139 BIM CONTROL ZONE President Accounting Operation President Human Resource Shop Manager Sale Welding Shop Supervisor Project Manager BIM Design & Engineer Technique Support Bridge Manager Shop Supervisor Shop Supervisor Cutting Delivery Material Paiting Parts & Templet Storage Erection Estimating BIM Manager BIM Support Network Support Project Project Project Figure 611. S Steel Company simul ation of using BIM organization structure chart
140 Control all BIM tools purchases and maintenance. The following are changes caused by BIM organization structure: The former design and engineer team has to finish training on using all BIM tools and be skil lful with all detailed software functions. They report to the BIM manager for BIM design and engineer ing work. The techni cal support personnel have to learn BIM tools as well. They have to keep the BIM network running through projects. They also need to ma intain all hardware and software, and keep all company and project document s safe. T he estimating department is merged with BIM design and engineer ing as a subunit. That is because some BIM tools have strong estimating function s Shop work positions are kept. A ll the shop sequences are controlled under the BIM model. The BIM control zone covers all stages of work and position s under the operation president. All departments are connected with the intranet network system and are controlled by the BIM model. These are the minor changes to the organization structure plan so that the company can keep its traditional work style. The BIM model is only a new tool for construction work. A ny costly changes may cause more conflict in the work. The BIM Model Cost and Implement ation This BIM model would have decisionmaking functions in it. All resolvable decision making questions are list ed under a search menu. Users can navigate these questions in a catalog box. Users can fill infor mation in different dialog boxes when requested Users can us e key words to search for match up questions and then select the proper decision making model. S Steel Company work packages include fabrication and erection subcontractor work. A rchitects shoul d give them drawing documents. I f they already have the architectur al drawings they have to translat e these 2D or 3D drawings to SDS/2 format before using Navisworks. The f abricator is a type of ETO (Engineer to Order) component producer. The S steel shop is using a CNC Automation Fabrication System and an I ntranet in the design and engineer ing
141 department so that the drawing orders can be sent directly to the machine and be created at the moment. CNC Automation Fabrication System us es the same 3D SDS/2 sh op drawings that the BIM /RFID decision model use s The BIM /RFID Decision Model can coordinate with this situation It uses Navisworks with the original SDS/2 3D shop drawings as well. BIM Brings Benefits to S Steel Company BIM can reduce mistakes that may happen through all stages of construction. SDS/2 is considered as one of the BIM tools It can develop a 3D detail ed model and generate connection detailing document s for either fabrication or erection. It can improve the efficiency of most existing steps in the 2D CAD process by increasing productivity and eliminating manually maintain ed consistency across multiple drawing files. BIM changes the production process itself by enabling degrees of prefabrication that have remain ed prohibitive in coordination c osts with existing information systems. BIM can substantially reduce lead times and make the construction process more flexible and less wasteful. (Eastman 2008) For S steel, the significant benefit is the coordinati on of the BIM models with AEC or other subcontractor s Autodesk Navisworks can be seen as the most functional BIM tool at files combination. Navisworks is not a modeling program, it links BIM 3D files into a Navisworks format (NWD) which is often a more useable file type than other format s Na visworks can run a schedule animation, sequencing animation, and clash detection. In this way, Navisworks has the ability to schedule the work flow of steel structure from start of prefabrication to finish of erection. The SDS/2 and CNC automation system cannot do the same job as Navisworks does. The BIM model can bring many benefits to erection work. T he BIM m odel is buil t from start of project when it ha s been designed at an architect s office T his model can be directly use d for steel erection. S Steel a wards about 30 projects average per year including bridges and
142 building projects. Their field erection teams can work for most of their projects with the rest of them sold to other steel structure companies. The erection team cannot share the fabrication f iles at the same time. J obsite orders or RFI were delay ed or confus ed These problems will be easil y resolved by BIM. This is an important improvement for S Steel. RFID Potential Usage S Steel is using a barcode system as the ir steel member identification method. RFID system has been used in many industry fields. S Steel is ready for deployment of an RFID system. The major differen ce between Bar code and RFID is the reading style and operation cost. From field responses to bar code use they found that usi ng bar code is much better than using hand painting and chalk mark. But there are problems there, for example, the damage on the barcode missing barcode wrong placement, or delivery date mixed up. These problems can be avoided when using RFID. RFID can h ave data memory so that each sequence can read the same information. RFID tags are strong er than barcode and more durable for storing. RFID is easy tracking at stor age and delivery when use GPS together It can be checked by each member of the team to avoi d the data comparison and delivery problems. If RFID had been us ed from the start of design process, RFID and its data would flow down to the whole project. BIM can use RFID as its symbol so that every detail ed part has its own identification numbe r It mak es estimating and production easier Feasibility Analysis of BIM for S Steel Company BIM can bring benefits to the engineer ing detailing and fabrication parts. BIM can improve the situation of S Steel It makes the AEC plan s easy to understand and avoids software conflicts Navisworks can fit SDS/2 very well in both 3D CAD and steel connection detail s RFID labels members in a uni que way for stor age delivery, and installation without confus es and mistak es. BIM uses RFID for data collection and ret rieval that makes steel
143 structure construction accurate. F igure 612 shows the BIM flow for S Steel Construction in both fabrication and erection. It shows a view of the future job scope of S Steel. As a conclusion of the above analysis and BIM research fo r S Steel Company, BIM can defi ni tely work for S Steel Company and bring more benefits to its workers and projects. Example of S Steel Workflow Using BIM /RFID Framework S Steel has automatic control machine using Computer N umerical Control (CNC) manufacture system. CNC manufacture system has a Function Block which is the key for collecting and ex ecuting operating orders and acting the machine. The orders made by machining feature based design system are done by the same tea m with detailing and engineering design in the company. How do BIM tools link with CNC manufacture control system? RFID as a digital data source can do a perfect linkage work. When the architect and engineer use BIM tools to design project, they can use th e RFID system to label the steel components and assign information to the RFID tag that remains attached to it through the entire project. When the CNC machine makes the cut, the RFID represent s the steel member. In this way, RFID works as information carr ier. S o the BIM /RFID Framework (B R F ) can link the CNC system using the RFID system. From the first activity shown in Figure 612, r eceiv ing the drawing, the BIM team creates 3D format Revit and Navisworks files with RFID used for the steel components. In this process, the 3D design software can use SDS/2 and Navisworks and the RFID coding system and database supports the decision making process. B i ding and contractor document are printed out by the BIM office support system.
144 Receive Drawing Estimate and Bid Sign Contract Prepare&Submit Shop Drawing Purchasing Revise Shop Drawing Engineering Design and Detailing Shop Production Install Components Delivery Prepare Erectiona&Crane Plan Steel on Site Crane Unload Erection Order Hoisting Sequence Anchor Rods Leveling Plate Column Base Plate Bolting and Welding Upload Column 123 Connecting Plan Preliminary Bolting Plumbing Up Safety Cbl Upload Beam 123 Temporary Bracing Girder First Columne Bolting and Welding Bracing Lateral Stability Column Splicing Perimeter Safety Cables Welding Shear Studs Roofing Inspection Fire Proofing Sequence 1 Sequence 2 Sequence 3 Sequence x Steel Decking RFID&GPS RFID&SDS/2 RFID,SDS/2&CNC Navisworks&SDS/2 RFID,SDS/2 Navisworks RFID&SDS2 Navisworks RFID&SDS/2 RFID&SDS/2 Navisworks&SDS/2 Navisworks&SDS/2 RFID&SDS/2 Figure 612. BIM work flo w for S Steel f abrication and e rection process
145 The d ecision making system tests the benefits and others factors. If t he bid is successful, the e ngineers and design department work with the BIM /RFID Framework With the selected RFID, the BIM detailed drawings are created when running the design decision systems and RFID database. In this process, the RFID database serves each steel component feature and design coding requirements to support the connection des ign. The design support system uses SDS/2 and Navisworks. The scheduling and planning job uses BDM to get the optimal erection plan. The process is: Steel components RFID group data are input in to BIM testing. Then the results are output to the decision su pport systems to simulate and find a n optimal plan. The shop work follows RFID members in detailing shop drawings. The BIM /RFID Framework sends orders to the CNC manufactur ing control system to cut the steel components. In this process, SDS2 and CNC control the manufacture, RFID acts as the shop drawing coding system. O ther fabrication activities are all under the BIM /RFID Framework control when us ing the RFID coding system. The e rection plan and processes have been discussed befo re. The Navisworks and SDS/2 are used as erection assistant systems for connecti on and welding work. In this workflow, the Navisworks acts as a main 4D BIM software. Its functions for simulation and 4D visualization need to be improved. A strong functional software and fast computer hardware can support more BIM decision making model functions. Time B ased S upply C hain M anagement On time D elivery Delivery is an important construction issue. T his is critical for steel structure s Steel structures have better strength to weight ratio than other construction materials They can be easily installed or dismantled The buildup duration of steel structure buildings are normally much short er than reinforce d concrete structure s In this case study, m ost S Steel Co mpanys
146 projects are over a million dollars. This gives them more pressure for ontime delivery because these projects are usually located in long distance. S chedules are very condensed on those projects as well The supply chain management (SCM) is very i mportant for S S teel and other parties on the project. The cost based supply chain is the SCM major research field. But for fabricator and erector, the steel price fluctuates seasonal ly so that the steel suppliers have to change the contract prices T he t i me issue is more important because the special character of the fabricator The f abricator needs a longer production time than the installation. The purchase orders need to be sent to mills T he shop drawings need to be detail ed as soon as the contract is signed. The shop needs to get ready for cutting and drilling as soon as the materials come in to storage. The welding and shop pre assembling need to be ready as soon as the metal cutting work is done. The storage needs to be ready for receiv ing the raw ste el material s, storing the finished members then waiting for shipping. All these processes take time In this case, delivery doe s not just begin from the storages gate to the fields gate, but it actually begin s from the day of signing the contract and en ds till the members are installed RFID and GPS are perfectly suitable for those ru s h work s Manufacturing System Integration (MSI) associated with fabrication process and delivery process are based on the supply chain management (SCM) model. MSI integrate d with BIM /RFID Framework has one important function, which is making decision on optimized supply plan to control the productive scheduling of fabrication and erection. Then BIM can reduce the design and production cycle time and make the c onstruction process less wasteful and more flexible. Reminders can be set up on the BIM schedule. The BIM model can make an optimized time flow. For example, if a user make a schedule for erect ing a group of member s on December
147 1st, the critical date of t he purchase order must be set on October 15th and the cutting must be ready between October 18th to 25th, the welding between October 19th to 27th, the painting between October 20th to 30th and delivery will be tween October 30 to December 1st. Also, the de livery weather, methods and roadmap will be show n on the delivery plan. The BIM /RFID Framework has a detail ed work description, ready for the support documents and installation plan for each part of the activity. Even the best schedule cannot predict some uncertain incidents. An example of that is the manufacturing facil i ty that S Steel built the previous year. The steel erection schedule had to be extended by one month because of an equipment delay. This equipment was shipped from India. It took two months by ship o transport. An unex pected thing happened when it arrived to USA board. The shipping box of equipment was made of untreated wood and this is against the C ustom regulation. The wood needs to be treated at someplace with equipment unl oading. This took about two weeks for waiting on the treat ment and re boxed. It took another two weeks for transport ing it to the loading place. This equipment needed to be put indoor and stay inside before the building envelope is finishe d so that it can be installed easier. All the steel erection and the successor tasks had to wait and were hence delay ed Us ing the BIM /RFID Framework what could S Steel have done for this case? The system will also have a mode block that has all ship ping information and C ustom regulations. The BIM/RFID Framework will show a check list and request instructions for shipping either domestic or overseas It will help avoid incident s and delays before they happen. Simulation testing for the shipping pr ocess may help in figur ing out all uncertainty problems and delivery methods. Also, a rearranged plan may be found when us ing RFID location data and BIM schedule support system to define the work space.
148 Erection S equence A nalysis Optimized S chedule Cons truction phases are complex characterized by a set of tasks or activities work ed by different subcontractors. The erection sequences are separated by different operat ing cranes. Cranes are operated by different operators. The owner contractor agreement may also contain a liquidated damage clause providing for compensatory damages due to delays. (AISC 1999) Project schedule s are based on an assumption of every party working at constant planning orders. But different parties have their own work style and qua lity. C ranes have varied conditions and weight limitation s Operators have skill levels and work abilit ies All these differences require decisions in making an optimized plan and helping the project finish on time. S teel erection jobs are usually separat ed by different sequences so that the user can schedule as many activities as they can. The t radition al method of steel structure construction is to follow the original schedule from purchase order to delivery. If a job is delay ed or its condition changed, the job site supervisor need s to file a RFI or RFC to the PM and GC s office, then to the fabricators. It takes at least two work days for a new schedule to be approv ed It has to have storage spaces at the shop and the job site in case of any schedule ch anges affecting the fabricator or erector. The BIM /RFID Framework can adjust schedule in minutes have real time jobsite feedback via the RFID system and disseminate the schedule via the I nt e rnet. RFID is use d as a control coding system for steel members. Its database has enough information for BIM decision making model to do optimal calculations and system support analysis For example, a fter inpu t t ing RFID in a BIM model, using simulation and matrix calculation can make an optimal ranking of steel erection order. It is happen some times waiting on jobsite when other work is blocking the sequence or working space accidentally Through a BIM /RFID Framework a jobsite zoning system may help arrange the space use and optim ize those operations.
149 Figure 613 show s the work flow of a construction project It compares the differences between the tradition al project control methods and BIM /RFID Framework controlled projects. BIM design and simulation may save little time compared with tradition al design methods. But the erection sequence saves much more time than tradition al project organization methods when us ing the BIM control model. In addition, it eliminates the mistakes and confusion when reading old 2D drawings looking f or right dimensions, or searching for connections or correct parts. BIM decision model can bring three major benefits to AEC. The f irst benefit is the time saving for scheduling and planning. Figure 613 shows a big lap when us ing tradition al methods for steel structure construction. The BIM /RFID Framework using the 4D real time control system gives erectors more flexible operating space and buffers for job arrangements between subcontractors. The s econd benefit is the space savin g for steel stor age When using the BIM /RFID Framework right ontime designed system can minim ize the needs for steel storage space either in the shop or on the jobsite. The third and biggest benefit is the effective ness of using RFID as a key coding parameter, BIM with Total Quality Control (TQC) and Flexibility Production System (FPS) to highly improve the steel structure construction producti vity TQC and FPS are smart IE (Intelligent Engineer) management techn ologies CNC is one of these techn ologies too. The common character of these techniques is the intelligent ability of the machine or software control Similar to the CNC system, it can automatically design the piece cutting plan in a given sheet of metal to have an op timiz ed result for material saving. By using the BIM database information the design decisionsupport system c a n be used to develop the best design result for shop worker s. The design is even better than t hat done by very experienced users.
150 Current CPM and PERT schedule methods have a reschedule function. When any activity changes in the process of project, users need to reschedule to make sure all relational activities follow the change too. Then a new schedule is created. In the BIM decision making model, an automatic optimization schedule function can make for a better planning and safety environment. Depending on these benefits, the BIM decision making model has the same intelligent functions in control and making decisions They can improve the sche dule detail s and perform real time sequences control for the job site. For the erection sequence, the BIM model can even make it possible for a short time cross sequences job arrange ment In the framework of the BIM /RFID Framework the schedule sequence is affected by almost all variable factors including building code, union rules, OSHA regulation, weather, time, cost, labor and quality. The change of project sequence not only impact s scheduling and planning, but also affect t he job situation and condition. The most important changes are focused on erection and crane plans. 4D BIM simulation and real time jobsite RFID control make the BIM /RFID Framework a feasible environment. Figure 614 shows a n animation of the structural steel erection process by sequence. The six sequences will slowly appear along with the working day in which hoisting of each sequence was completed. The last images to appear are of the masonry stair and elevator shafts. They were built after the frame was erected. The steel frame was connected to the vertical shafts to provide permanent lateral stability of the frame.
151 S Design Shop Installation Delivery Erection Inspection Engineer Detailing Shop Pruduction Beam 10A0301 Mill Tradition Sequence 2 Sequence1 Sequence 4 Sequence 3 Delivery Flow Delivery Flow Purchase Order Storage Original Scheduling AEC BIM Team Shop Installation Delivery Erection Inspection Detailing Shop Pruduction SN#: B10A0301 Mill BIM/RFID Framework Sequence 2 Sequence1 Sequence 4 Sequence 3 Delivery Flow Delivery Flow Purchase Order Field BIM Team RFID S Storage Adjustable Scheduling and Planning Figure 613. Tradition construction method versus BIM /RFID Framework schedule and delivery flow
152 Figure 614. The s imulation of BIM /RFID Framework operation for steel structure erection job sequences (AISC 2005 )
153 Two crane locations were used for this project. Location 1 was used to erect sequences 1, 3, and 5. Location 2 was used to erect sequences 2, 4, and 6. The crane was moved to the appropriate location for each sequence. Crane locations were approximately 45 feet from the face of the building. This is a detailed schedule of the ere ction process of the structural steel frame. In this project an average of 40 pieces of steel were hoisted per day. Hoisting, bolt up, detail work, decking and stud activities are performed by sequence. Hoisting consists of lifting and placing steel member s into their appropriate position and temporarily fastening them using several bolts and/or welds. Plumbing up refers to the vertical alignment of the frame. Final bolt up refers to tightening the bolts which connect the components of the structure. (AISC 2005) Using the BIM /RFID Framework can improve this program All steel components are RFID tagged. F rom first day, it is clear that crew s work skill between sequences is different. By using the BIM/ RFID Framework crane A finis hed 60 pieces of steel member when crane B only finished 40 pieces and one minor accidentally operation. C rane B responds for sequence 2, 4 and 6 which is east parts floor 1 and floor 3, west side floor 2 which cross over with crane A s work zone. Here is a problem. The original schedule designed for crane A and B is for the average same workloads. In this case, crane B would be far more delay than crane A. It is possible to delay the whole project if the current process is kept This situation is normal and was hard to solve before because of the BIM/ RFID model the situation is improved. The RFID tag gives the real time jobsite information to the 4D BIM /RFID Framework It makes it easy to control the sequence erection by pieces. The erection plan can follow the RFID marked 4D BIM /RFID Framework to adjust the erection member sequence in a safe and short time. By timing the two crane progress, the crane erection plan can be flexible for changes. The
154 changes come from two parts. One is the erection order, another is planning change. The erection order change can help crane B do easy the hoisting while crane A can handle most of the hard members. Planning change can make follow up activity ready for the possible work c hange for whatever time or work zone The RFID 4D BIM /RFID Framework can make these changes more correctly and smoothly. Summary The BIM /RFID Framework has three main parts. The very first part is the database, it s information come s from many resources and its need s to be retrieved using a convenient filter system so that users can have information that they really want and not be bothered by a lot o f data. The BIM /RFID Framework has to have data transaction and dialog integration functions compatible with different software and functions integration. A model typically may changes many times prior to creating the construction documentation. Linking models prevents the accidental editing, moving, or deleting of model elements built by the design team. Autodesk Navisworks has the most robust tool in which these models are compiled and tested. Using the Coordination Review tool in Revit is another effective way of letting a BIM user knows whether linked elements have been shifted during use or because of updates (Hardin 2009). The BIM /RFID Framework from the designer helps in detailing items and scoping them as well as coordinating owner driven design and program shifts. The BIM team can use a BIM pit or BIM huddle to help the owner who has a fast track project in using BIM to find a way to rapidly advance a project. In this case, the BIM team at jobsite office can have members work together to model and virtually construct the proposed structure. Autodesk Integrated project delivery (IPD) is one of the emerging standards for early collaboration and effective decision making in the building industry. IPD has compatibility condition for all Autodesk software so
155 that the BIM decision model can develop a proje ct management function for the whole project instead of the design and simulation phase only. The key module for implementing the model is decisionmaking tools. Decision Tree and other statistic tools are using to analyze and verify the data which can support management team making decision. The RFID, GPS and webtransaction technique are used to develop a real time 4D erection jobsite BIM /RFID Framework R FID is the key of real time 4D jobsite control too. It not only gives the steel members identification, but also connected detailing data of steel members with BIM Model. In this case, RFID marks every detail change relative to BIM /RFID Framework and result s in BIM data updating whenever steel member data are changed. In develop ing a real time BIM 4D model by using RFID, there are still some barriers from network technology, 4D software, RFID tags, data formatting and transferring C urrent wireless network barcode readers ha ve many limitations for effe ctive data transferring RFID reading data are not easily transferred to central computers. The Wi Fi maybe an answer for this problem, but it needs to have an Internet system support. 4D tools such as Navisworks and Vico have 4D functionality but do not s upport real time function. RFID tag needs special material for use on steel members so that RFID can adhere to the surface of steel stably and firmly without any damages. RFID data format and transfer s are still argued by researcher and field personnel bec ause there is no proper equipment available. The PDA has been used for some testing projects, but it just acts as a barcode scanner not a RFID scanner. This process can only deliver a daily update but not real time simulation.
156 CHAPTER 7 CONCLUSIONS AND RECOMMENDATIONS R e search S ummary and C ontribution This research proposes a model that combines web based four dimensional ( 4D ) Building Information Modeling ( BIM ) Radio Frequency Identification ( RFID) and Manufacturing Systems Integration (MSI). The model focuses on steel fabrication and site steel erection. The program is based on a multi purpose model, which uses RFID plus steel series code and color codes systems to differentiate between steel pieces, to help control the schedule of a project, and to describe the entire scope of construction. It relies on a 3D graphic scheduling to display real time steel erection. It helps with planning jobs, verifying erection information, controlling job sequence, site inspection, and other field related jobs. This BIM /RFID Framework also has more functions on helping AEC to make decisions by using the progress shown on the BIM control and testing system. Building Information Modeling (BIM) with four dimensional (4D) technologies and Manufacturing Systems Integration (MSI) make it possible to develop an effective designplanning fabrication erection intranet based system. The significance of this model is to help to minimize project mistakes. This model deals with uncertainty problems, w hich is the area that needs a lot of investigation. If project managers can view the current project situation and predict the possible results in a simulation environment, it will be easy for them to control the changes and avoid the risks. In addition, p roject managers can find out solutions to deal with the possible mistakes or errors. The BIM /RFID Framework is based on a data base and a m odel base. The retriev al of useful and accurate data gives the decision maker the possibili ty of making optimized decision. Testing was used to verify the feasibility of the model.
157 Limitations and B arriers of the BIM /RFID Framework Database Problems M any functions have been developed in BIM research which is based on different database system s. But current construction databases are too simple to support these functions in work ing properly. Each BIM tool has its own data resource when it is developed on a case by case basis. Unfortunately, even these databases are not open to the public. Data mining technology is also a limitation to the BIM /RFID Framework functionality. Data retriev al becomes a problem when decision support system needs quali fied data to make decision. Either useless data retrieved or too many data elements to work on to make a choice confuse users. In this case, data mining technique needs to be impro ved for the quality of data supply and data retriev al Lack of data access Lack of data is a critical limitation for construction industry to use BIM functions. This limitation has two reasons: one is because the data accumulation needs time; another reason is because data security and copyrights limit database general use by different parties. Data safety problem The concern of data safety has limited BIM development as well. This is because of the na ture of the construction industry. General contractors control the whole project and give orders to subcontractor to finish their job s. When BIM is used for a project, subcontractors are legally using BIM resource and reading proj ect information from the same BIM environment and systems. This brings a problem for data safety and user limitations. Current BIM tools rarely treat this problem in their functional design. BIM projects are controlled by consulting team member s or the PM team, subcontractors are allow ed to us e BIM tools to review detail project information only if they c ome to PM office. In this case, BIM only
158 has partial AEC use and its access is limited for subcontractors. This is a big barrier for BIM us age Data rel iability BIM tools are marketed by different companies, designers, programmers and developing software. Navisworks is a main BIM tool for project control but they still need Timberline for estimating, Primavera Project Planning or Microsoft Project for s cheduling, and T e kla or CIS/2 for detail steel connections, all these program may have some conflict s as well. Navisworks is able to access different data file format s Visualization Quality T ransaction and T ransfer Confliction BIM tools have functions of 3D and 4D imag ing. But the imaging has no good quality for transaction and transferred imaging. Decision support systems support the model structure and make sure the model is going int o the right direction. Using RFID with BIM for the structural steel pr oject is still a new research field. Despite the power and availability of 3D/4D tools, their us e is still not common in most areas of design and construction (Issa 2003). 4D is still not a widely accept ed design/construction tool in the construction indus try. Field Operations Internet and Network Limitation The performance speed of on site computers also depends on the speed of Internet and the hardware involved. The visualization sensor and virtual navigation controllers need to be reconsidered to fit d ata entry and information tracking. The job environment also limit s the use of network connection on jobsite computers especially for remote project s The BIM tools environment and their technical capabilities also need to be improved. In this situation, network connection techniques and jobsite intranet functions also need to be improved. WI FI works fine at a normal job site, but for a larger jobsite a set receiver and transmitter is needed to hold the data and transfer it to a wired computer which is co nnected with the BIM control center.
159 Safety C ontrol S till D epends on H uman R esponsibility For a long time, researchers have wanted to have a computer system to control jobsite safety so that workers can work at a hazards free working space. BIM tools can link with the safety database and have functions like safety tracking and jobsite protection system, but they still need responsible humans to maintain them. This problem gives the BIM /RFID Framework some potential uncertainty results after a decision had been made. All the aforementioned problems and barriers can affect the result of the BIM /RFID Framework In other words, the BIM /RFID Framework is based on a reasonable result of statistic probability guessing and technique calculation Recommendations for Future Research The future development work for this research will include simplifying and standardizing the BIM 4D operations so that various resources can be linked and displayed correctly without conflicts or errors. Furthermore, the web based 4D visua lization system has huge imaging files. It is usually too large to transfer in the field. It is still a problem for data transfer between AEC offices to jobsite office. (see Figure 7 1) GIS and GPS have been used on construction projects for a while, but t here is no corresponding program to link them with BIM. The future of GIS developments relative to BIM functions requires GIS to have a detail ed material database in layers which include BIM components and structure information. RFID and 4D BIM can give im proved performance if future improved GIS and GPS systems can assist RFID in locating in real time structural steel members.
160 Design RFIDSN: B10A0301 Manufacture and Fabrication Delivery Erection Inspection Detailing Construction Begin BIM Contract Model Outline Simulation and Revises Delivery Field BIM Control Files Information Transaction Manufacture and Fabrication AEC Design Approved All information and Documents Collecting RFI&RFC All Document Close Facility Mangement Inspection BIM RFI & RFC System Beam 10A0301 Designer Febricator Engineer Deliver MEP Subcontractor Inspector BIM Team1 Febricator Field Office (Erector&MEP Subcontractor) Inspector Erector Contractor Bid Designer Deliver Contractor Facilities BIM Team 2 BIM Team 3 BIM Center Tradition BIM Current Field office Field Office Punch List RFIDSN: B10A0301 BIM Contract Model Outline Simulation and Revises Delivery Field BIM Control Manufacture and Fabrication AEC Design Approved Data Center RFI&RFC All Document Close Facility Mangement Inspection BIM RFI & RFC System Febricator Field BIM Office (Erector & MEP Subcontractors) Inspector Deliver Facilities AEC BIM Administration Center BIM Future Engineer Figure 71. Tradition al c onstruction versus BIM c urrent and f uture planning and organization
161 Robotically site layout will also be a very interesting future research topic. It should directly display BIM images from the simulation model picture to the real world. On the other hand, a 3D imag e could also be bu ilt up by scanning an existing building so that users can have a direct 3D model when the original building documents are lost Finally, d ata mining and information retriev al technique s still need more improvement s and advancement to make the decision in formation system more powerful. R FID database can be use as linkage of projects so that followed similar projects can find a better solution for unexpected problems. A smart coding system is developing for better data mining and data retrieval solutions I n a near future, BIM database m ay be opene d and used by more construction companies and projects.
162 APPENDIX A SAFETY STANDARDS FOR CONSTRUCTION WORK (Washington State Dept. of Labor and Industries) Chapter 296 155 WAC Part P Construction Work Steel Erec tion
193 APPENDIX B SITE SPECIFIC ERECTI ON PLAN AND CHECK LI ST ( EXAMPLE FORM)
198 APPENDIX C STEEL ST R U CTURE DESIGN TABLES (AISC) (HARWARD 1989)
200 LIST OF REFERENCES A deli H. ( 19 88). Interactive MicrocomputerAided Structural Steel Design ., Prentice Hall Inc., Englewood Cliffs, New Jersey AGC (2006). The AGC's BIM Initiatives and the Contractor's Guide to BIM. The Associated General Contractors of America.
201 Cormen T. H., Leiserson C. E., Rivest R. L. and. Stein C., (2001). Single Source Shortest Paths ". Introduction to Algorithms (2nd). Cambridge, Massachusetts : MIT Press. pp. 580 619. Crowley, A. J. and Watson, A. S. (2000). CIMsteel Integration Standards Release 2. The Steel Const ruction Institute, < http://www.cis2.org/> (Feb. 21, 2009). Dawood, N., Sriprasert, E., Mallasi, Z., and Hobbs, B. (2002). Development of an integrated information resource base for 4D/VR construction process simulation. Automation in Construction, 12, 123131. Dessler, G (2001). Management: Leading People and Organizations in the 21st Century PrenticeHall, Inc., Upper Saddle River, New Jersey 07458. Dressen, D. (2008). Large Memory RFID System Solution. www.atmel.com
202 Hayward, I., and Weare, F. (1989). Steel Detailers Manual BSP Professional Books, Blackwell Scientific Publications Ltd., Osney Mead, Oxford. Howard R., and Bjork, B. (2007). Building Information Models Experts Views on BIM/IFC Developments. CIB w78 23nd Inter national Conference on Information Technology in Construction. International Council for Research and Innovation in Building and Construction, Dresden, Maribor, Slovenia, CIB. Hubbard, D. (2007). How to Measure Anything: Finding the Value of Intangibles in Business John Wiley & Sons London. Hubbard, D. (2009). The Failure of Risk Management: Why It's Broken and How to Fix It John Wiley & Sons London. Hu, W. (2008). Integration of RFID and 4D CAD in Construction Management Journal of Tsinghua Science and Technology. 13(S1), 151157. Issa, R. R.A., Flood, I., and OBrien, W.J. (2003). 4D CAD and Visualization in Construction: Developments and Applications A.A. Balkema Publishers, Lisse. Johnston, B. G., Lin, F. (1974). Basic Steel Design. Civil Engineering and Engineering Mechanics Series, PrenticeHall, Inc., Englewood Cliffs, N.J. Kenley R ,, and Seppanen, o. ( 2009). Locationbased Management for Construction, Spon Press, New York, NY. Koo, B. and Fischer, M. (2000). Feasibility of 4D CAD in commercial construction. Journal of Construction Engineering and Management 126(4), 251260. Karttam, N. A., and Levitt, R. E. (1990). "Intelligent planning of construction projects." Proc., Journal of Computing in Civil Engine ering 4(2), 6. Lipman R. R. and Reed K. A. (2006). Visualization of Structural Steel Product Models. ITcon 8, 5164. Lipman R. R. and Reed K. A. (2000). Using VRML in Construction Industry Applications. Web3D VRML 2000 Symposium Virtual Worlds, Monterey, CA, 21 24. Leicht, R. M. and Messner, J. I. (2007). Comparing traditional schematic design documentation to a schematic building information model. CIB w78 23nd Inter national Conference on Information Technology in Construction. International Council for Research and Innovation in Building and Construction, Dresden, Maribor, Slovenia, CIB. Miles, S.. B. Sarma, S. E., and Williams J. R. ( 2008). RFID T echnology and Applications Cambridge University Press, Cambridge UK. Mooney, J. D. (2004). IFIP 18th Computer Congress Tutorials. Developing Portable Software Kluwer Academic Publisher, Toulouse, France, 5484.
203 NIST (2009). Manufacturing System Integration. N ational I nstitute of S tandards and T e chnology. < http://www.nist.gov/mel/msid/index.cfm > (Feb. 21, 2009). Newman, A. (1997). Metal Building Systems McGraw Hill, New York Ni cholas Metropolis (1987), The beginning of the Monte Carlo method, Los Alamos Science 1987 Special Issue dedicated to Stanislaw Ulam Olbina, S. (2005). Decision making framework for the selection and Design of Shading Devices PhD Dissertation, the Virginia Polytechnic Institute and State University, Blacksburg, VA. OSHA (2007). Occupational Safety and Health Simplified for the Construction Indus try, Government Institutes, an imprint of The Scarecrow Press, Inc., Lanham, Maryland. Pazlar, T. and Turk, Z. (2007). Evaluation of IFC Optimization. CIB w78 23nd Inter national Conference on Information Technology in Construction. International Council for Research and Innovation in Building and Construction, Dresden, Maribor, Slovenia, CIB. Podbreznik, P. and Rebolj, D. (2007). Real Time Activity Tracking System The development Process. CIB w78 23nd Inter national Conference on Information Tec hnology in Construction. International Council for Research and Innovation in Building and Construction, Dresden, Maribor, Slovenia, CIB. ProjectDox (2009). Project Information Management. Avolve Software Corporation ASC.
204 Sprague, R. and Carlson, E. (1982). Building Effective Decision Support Systems Prentice Hall, London. STEP (2006). STDeveloper. STEP Tools, Inc.
205 BIOGRAPHICAL SKETCH Wei Shi was born in Xian city China. He earned his PhD from the M.E. Rinker Sr. School of Building Construction at the University of Florida, Gainesville, Florida. He also earned his Master of Science in Real Estate and Insurance Degree from Warrington College of Business Administrati on at the University of Florida while working on his PhD Degree. He also holds a M BC from the M.E. Rinker Sr. School of Building Construction at the University of Florida and a Master of Engineer and BS in construction engineering and management from the Xian University of Architecture and Technology, China. He has his wife Dr. Haiyan Xie, their son Owen Shi daughter Catherine Xie Shi who reside in the USA.