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Alternative Support Structures for Cantilever Signal/Sign Structures

Permanent Link: http://ufdc.ufl.edu/UFE0041396/00001

Material Information

Title: Alternative Support Structures for Cantilever Signal/Sign Structures
Physical Description: 1 online resource (215 p.)
Language: english
Creator: Jenner, Kathryn
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2010

Subjects

Subjects / Keywords: anchorage, anchors, cantilever, signs, structures, torsion, wind
Civil and Coastal Engineering -- Dissertations, Academic -- UF
Genre: Civil Engineering thesis, M.E.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract: Alternative Support Structures for Cantilever Signal/Sign Structures During the 2004 hurricane season, several anchor embedment failures of the support structures of cantilever signal/sign structures occurred. A previous research program determined the cause of these failures was by concrete breakout due to shear on the anchors directed parallel to the edge of the foundation. The purpose of the current research program was to take the knowledge obtained on the previous research program and identify a suitable alternative support structure without the use of anchor bolts. After a literature review and experimental testing, it was determined that an embedded pipe with welded plates was a suitable alternative support structure. The torsion could be adequately transferred to the support structure concrete through the vertical torsional plates and the flexure could be adequately transferred to the concrete through the welded annular plate on the bottom of the pipe. Furthermore, it was determined that the alternative selected was not only a viable alternative to the anchor bolt system, but it had greater strength for a given foundation size than the anchor bolt system. The test specimens were designed to fail by concrete breakout originating from the torsional and flexural plates and to preclude other failure modes. The results of the testing indicated that the concrete breakout was the failure mode for the embedded pipe and plate configuration and that the concrete breakout strength could be accurately predicted using modified equations for concrete breakout from ACI 318-08 Appendix D. The results of these tests led to the development of guidelines for the design of the embedded pipe and plate configuration. Recommendations for future testing include an alternative base connection that precludes the use of annular plates.
General Note: In the series University of Florida Digital Collections.
General Note: Includes vita.
Bibliography: Includes bibliographical references.
Source of Description: Description based on online resource; title from PDF title page.
Source of Description: This bibliographic record is available under the Creative Commons CC0 public domain dedication. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
Statement of Responsibility: by Kathryn Jenner.
Thesis: Thesis (M.E.)--University of Florida, 2010.
Local: Adviser: Cook, Ronald A.
Electronic Access: RESTRICTED TO UF STUDENTS, STAFF, FACULTY, AND ON-CAMPUS USE UNTIL 2010-10-31

Record Information

Source Institution: UFRGP
Rights Management: Applicable rights reserved.
Classification: lcc - LD1780 2010
System ID: UFE0041396:00001

Permanent Link: http://ufdc.ufl.edu/UFE0041396/00001

Material Information

Title: Alternative Support Structures for Cantilever Signal/Sign Structures
Physical Description: 1 online resource (215 p.)
Language: english
Creator: Jenner, Kathryn
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2010

Subjects

Subjects / Keywords: anchorage, anchors, cantilever, signs, structures, torsion, wind
Civil and Coastal Engineering -- Dissertations, Academic -- UF
Genre: Civil Engineering thesis, M.E.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract: Alternative Support Structures for Cantilever Signal/Sign Structures During the 2004 hurricane season, several anchor embedment failures of the support structures of cantilever signal/sign structures occurred. A previous research program determined the cause of these failures was by concrete breakout due to shear on the anchors directed parallel to the edge of the foundation. The purpose of the current research program was to take the knowledge obtained on the previous research program and identify a suitable alternative support structure without the use of anchor bolts. After a literature review and experimental testing, it was determined that an embedded pipe with welded plates was a suitable alternative support structure. The torsion could be adequately transferred to the support structure concrete through the vertical torsional plates and the flexure could be adequately transferred to the concrete through the welded annular plate on the bottom of the pipe. Furthermore, it was determined that the alternative selected was not only a viable alternative to the anchor bolt system, but it had greater strength for a given foundation size than the anchor bolt system. The test specimens were designed to fail by concrete breakout originating from the torsional and flexural plates and to preclude other failure modes. The results of the testing indicated that the concrete breakout was the failure mode for the embedded pipe and plate configuration and that the concrete breakout strength could be accurately predicted using modified equations for concrete breakout from ACI 318-08 Appendix D. The results of these tests led to the development of guidelines for the design of the embedded pipe and plate configuration. Recommendations for future testing include an alternative base connection that precludes the use of annular plates.
General Note: In the series University of Florida Digital Collections.
General Note: Includes vita.
Bibliography: Includes bibliographical references.
Source of Description: Description based on online resource; title from PDF title page.
Source of Description: This bibliographic record is available under the Creative Commons CC0 public domain dedication. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
Statement of Responsibility: by Kathryn Jenner.
Thesis: Thesis (M.E.)--University of Florida, 2010.
Local: Adviser: Cook, Ronald A.
Electronic Access: RESTRICTED TO UF STUDENTS, STAFF, FACULTY, AND ON-CAMPUS USE UNTIL 2010-10-31

Record Information

Source Institution: UFRGP
Rights Management: Applicable rights reserved.
Classification: lcc - LD1780 2010
System ID: UFE0041396:00001


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1 ALTERNATIVE SUPPORT STRUCTURES FOR CANTILEVER SIGNAL/SIGN STRUCTURES By KATHRYN L. JENNER A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF ENGINEERING UNIVERSITY OF FLORIDA 2010

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2 2010 Kathryn L. Jenner

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3 To my parents, Joann and Stu Without your support, I would not have been able to accomplish this.

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4 ACKNOWLEDGMENTS I would like to acknowledge and thank the Florida Department of Transportation for providing the funding for this research project. This project was a collaborative effort between the University of Florida and the FDOT Structures Re search Laboratory in Tallahassee. I would also like to acknowledge and thank Dr. Ronald A. Cook for continually providing advice and knowledge to help make this project successful.

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5 TABLE OF CONTENTS ACKNOWLEDGMENTS ...............................................................................................................4 page LIST OF TABLES ...........................................................................................................................8 LIST OF FIGURES .........................................................................................................................9 ABSTRACT ...................................................................................................................................13 CHAPTER 1 INTRODUCTION ..................................................................................................................15 2 BACKGROUND ....................................................................................................................17 2.1 Current Anchor B olt Foundation System ......................................................................17 2.2 Alternative Foundation Systems ...................................................................................20 2.2.1 Steel Pipes with Plates Welded at Four Locations ............................................20 2.2.2 Geometric Hollow Section ................................................................................21 2.2.3 Pipe with Welded Studs ....................................................................................22 2.2.4 Helical Pipes .....................................................................................................22 2.2.5 Embedded Geometric Tapered Section .............................................................23 2.3 Alternative Foundations from Other Industries ............................................................23 2.3.1 Transmission Line Foundations ........................................................................24 2.3.2 Wind Turbine Foundations ...............................................................................26 2.3.3 Cellular Tower Foundations ..............................................................................27 2.3.4 Advertising Monopole Foundations ..................................................................28 2.4 Selection ........................................................................................................................28 3 DESIGN IMPLICATIONS ....................................................................................................38 3.1 Design for Torsion ........................................................................................................38 3.1.1 Equi valent Concrete Breakout Strength in Shear ..............................................38 3.1.2 Equivalent Side Face Blowout Strength ...........................................................43 3.2 Design for Flexure ........................................................................................................44 3.2.1 Equi valent Concrete Breakout Strength in Shear ..............................................45 3.2.2 Equivalent Side Face Blowout Strength ...........................................................46 3.3 Design Implications Summary ......................................................................................48 4 DEVELOPMENT OF EXPERIMENTAL PROGRAM ........................................................56 4.1 Description of Test Apparatus ......................................................................................57 4.2 Embedded Pipe and Plate Design .................................................................................59 4.2.1 Concrete Breakout and Bearing Strength ..........................................................59 4.2.2 Welded Stiffener Plates Design ........................................................................60

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6 4.2.3 Annular Flexural Plate Design ..........................................................................61 4.2.4 Annular Base Plate Design ................................................................................62 4.2.5 Pipe Design .......................................................................................................62 4.3 Concrete Shaft Design ..................................................................................................62 4.3.1 Concrete Shaft Diameter Design .......................................................................63 4.3.2 Torsion Design ..................................................................................................64 4.3.3 Longitudinal and Transverse Reinforcement ....................................................64 4.3.4 Flexure Design ..................................................................................................65 4.4 Concrete Block and Tie Down Design .........................................................................65 4.5 Instrumentation .............................................................................................................66 4.6 Summary of Torsion Design .........................................................................................67 4.7 Summary of Torsion and Flexure Design .....................................................................68 5 EXPERIMENTAL TEST RESULTS .....................................................................................77 5.1 Torsion Test ..................................................................................................................77 5.1.1 Behavior of Specimen During Testing ..............................................................77 5.1.2 Summary of LVDT Test Results ......................................................................78 5.1.3 Summary of Torsion Test .................................................................................78 5.2 Torsion and Flexure Test ..............................................................................................79 5.2.1 Behavior of Specimen During Testing ..............................................................79 5.2.2 Summary of LVDT Test Results ......................................................................80 5.2.3 Summary of Torsion and Flexure Test .............................................................82 6 SUMMARY, CONCLUSIONS, AND RECOMMENDATIONS .........................................90 6.1 Implications of Test Results ..........................................................................................90 6.1.1 Torsion Test ......................................................................................................90 6.1.2 Torsion and Flexure Test ..................................................................................91 6.2 Recommendations for Future Testing ...........................................................................91 6.2.1 Introduction and Background ............................................................................91 6.2.2 Tapered Embedded Steel Pipe and Plate Option with Bolted Slip Base Connection ........................................................................................................94 6.2.3 Embedded Steel Pipe and Plate Option with Grouted Slip Base Connection ...95 6.2.4 Embedded Concrete Pipe with Bolts Option with Bolted Slip Base Connection ........................................................................................................97 6.2.5 Cast in Place Solid Concrete Pedestal with Bolted Slip Base Connection .......98 6.2.6 Embedded Concrete Pipe with Bolts Option with Grouted Splice to Concrete Monopole ...........................................................................................99 6.2.7 Embedded Steel Pipe and Hoops with Grouted Slip Base Connection ..........100 6.2.8 Embedded Steel Pipe and Plates with Bolted Plate Connection .....................101 6.2.9 Embedded Steel Pipe and Plates with Welded Sleeve Connection .................102 6.2.10 Summary of Recommendations for Future Testing ........................................103 6.3 Summary .....................................................................................................................103

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7 APPENDIX A TEST APP ARATUS DRAWINGS ......................................................................................110 B DESIGN CALCULATIONS ................................................................................................121 Torsion Design Calculations .................................................................................................121 Tors ion and Flexure Design Calculations .............................................................................152 C TEST DATA .........................................................................................................................186 Torsion Test Data .................................................................................................................186 Torsion and Flexure Test Data .............................................................................................188 D DESIGN GUIDELINES .......................................................................................................191 Base Connect ion Design .......................................................................................................191 Embedded Pipe Design .........................................................................................................192 Embedded Pipe and Torsion Plates Design ..........................................................................192 Embedded Pipe and Flexure Plate Design ............................................................................194 Concrete Pedestal Reinforcement .........................................................................................196 Sample Design Guidelines ....................................................................................................200 LIST OF REFERENCES .............................................................................................................213 BIOGRAPHICAL SKETCH .......................................................................................................215

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8 LIST OF TABLES Table page 21 Support structure foundation frequency of use ..................................................................30 41 Summary of pertinent design strengths for torsion test with 5500 psi concrete ................76 42 Summary of pertinent design strengths for torsion and flexure test with 5500 psi concrete ..............................................................................................................................76

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9 LIST OF FIGURES Figure page 11 Failed cantilever sign structure ..........................................................................................16 12 Failed foundation during post failure excavation ..............................................................16 21 How torsional and flexural moments are transferred using anchor bolts ..........................30 22 Alternative foundation: steel pipe with four welded plates ...............................................31 23 Leveling nut detail .............................................................................................................31 24 Alternate foundation: geometric hollow section ................................................................32 25 Alternate foundation: pipe with welded studs ...................................................................32 26 Alternate foundation: helical pipes ....................................................................................33 27 Alternate foundation: geometric tape red section ...............................................................33 28 Cast in place foundation for transmission lines ................................................................34 29 Potential forces acting on a transmission line foundation .................................................34 210 Drilled concrete piles for transmission lines ......................................................................35 211 Typical transmission line structures compared to a cantilever sign structure ...................35 212 Prestressed soil anchor .......................................................................................................36 213 Grouted soil anchors ..........................................................................................................36 214 Mat foundation for wind turbi nes ......................................................................................37 215 Pad and pier foundations for wind turbines .......................................................................37 31 Concrete breakout of an anchor caused by shear directed parallel to the edge for a cylindrical foundation ........................................................................................................49 32 Differences between concrete breakout failures for anchor bolts in shear and embedded pipe and plate section in torsion .......................................................................49 33 Concrete breakout formula for an anchor loaded in shear .................................................49 34 Shear breakout of a single anchor in rectangular concrete ................................................50 35 Shear breakout for a single anchor in cylindrical concrete ................................................50

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10 36 Determination of AVcp based on section ................................................................................................................................51 37 Similarities of failure cones in side face blowout of a headed anchor in tension and the embedded pipe and plate section in torsion .................................................................52 38 Concrete sideface blowout equation for a headed anchor in tension ...............................52 39 Schematic of anticipated failure and bearing area of torsion plate ....................................53 310 Flexure resolved into a tension and compression on an anchor bolt system and the proposed system .................................................................................................................53 311 The tensile and compressive forces seen as shears acting parallel to an edge ...................54 312 Determination of AVcfp based on section ................................................................................................................................54 313 Illustration of bearing area on flexural plate for side face blowout calculations ..............55 314 Flexural plate bearing area for side face blowout calculations .........................................55 41 Pr edicted concrete breakout failure ...................................................................................69 42 Schematic of torsion test specimen ....................................................................................69 43 Schematic of torsion and flexure test specimen .................................................................70 44 Front view of torsion test setup ..........................................................................................70 45 Top view of torsion test setup ............................................................................................71 46 Side view of torsion test setup ...........................................................................................71 47 Views of the embedded torsion pipe section .....................................................................72 48 Isometric view of embedded torsion and flexural pipe section for the second test ...........72 49 Breakout overlap of the torsional and flexural breakouts ..................................................73 410 Interaction between torsion and flexure for concrete breakout .........................................73 411 Fabricated pipe and plate apparatus ...................................................................................74 412 Arrangement of the LVDTs on base plate .........................................................................74 413 Arrangement of the LVDTs on the top of the concrete shaft ............................................75 414 Arrangement of the LVDTs on the bottom of the concrete shaft ......................................75

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11 415 Arrangement of the LVDTs at the load location ...............................................................75 51 Lines drawn on base plate to show bolt slippage ...............................................................83 52 Formation of torsional cracks ............................................................................................83 53 Formation of concrete breakout failure cracks ..................................................................84 54 Concrete breakout failure cracks widen .............................................................................84 55 Specimen at failure ............................................................................................................85 56 Torsional moment and rotation plot for base plate of torsion test .....................................85 57 Torsional moment and rotation plot for torsion test ..........................................................86 58 Test specimen prior to testing ............................................................................................86 59 Torsional and flexural cracks forming ...............................................................................87 510 Formation of concrete breakout failure cracks in second test ............................................87 511 Widening of concrete breakout failure cracks in second test ............................................88 512 Load and torsional rotation of base plate for torsion and flexure test ...............................88 513 Load and flexural rotation for the second test ...................................................................89 514 Load and torsional rotation for test specimen for the second test ......................................89 61 Typical sign/signal base connection ................................................................................105 62 Embedded steel pipe and plate option with slip base connection ....................................105 63 FDOT Design Standards Index No. 11860......................................................................106 64 Embedded steel pipe and plate option with grouted slip base connection .......................106 65 Embedded concrete pipe and plate option with slip base connection ..............................107 66 Cast in Place solid concrete pedestal with slip base connection .....................................107 67 Embedded concrete pipe with bolts option with grouted splice to concrete monopole ...108 68 Embedded steel pipe and hoops with grouted slip base connection ................................108 69 Embedded steel pipe and plates with bolted plate connection .........................................109 610 Embedded steel pipe and plate with welded sleeve connection ......................................109

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12 A 1 Dimensioned front elevation drawing of torsion test apparatus ......................................110 A 2 Dimensioned plan view drawing of torsion test apparatus ..............................................111 A 3 Dimensioned side elevation drawing of torsion test apparatus ........................................112 A 4 Dimensioned view of channel tie down for torsion test apparatus ..................................113 A 5 Dimensioned drawings of embedded pipe and plate for torsion test ...............................114 A 6 Dimensioned front elevation drawing of torsion and flexure test apparatus ...................115 A 7 Dimensioned plan drawing of torsion and flexure test apparatus ....................................116 A 8 Dimensione d side view drawing of torsion and flexure test apparatus ...........................117 A 9 Dimensioned drawing of channel tie down for torsion and flexure test ..........................118 A 10 Dimensioned drawing of flexure extension pipe for torsion and flexure test ..................119 A 11 Dimensioned view of embedded pipe and plates for torsion and flexure test .................120 C 1 Moment and rotation plot for base plate of torsion test ...................................................186 C 2 Moment and torsional rotation plot for torsion test .........................................................187 C 3 Load and torsional rotation of base plate for torsion and flexure test .............................188 C 4 Load and flexural rotati on for torsion and flexure test ....................................................189 C 5 Load and torsional rotation for torsion and flexure test ...................................................190 D 1 Depiction of the elements described in the design guidelines .........................................197 D 2 Depiction of dimensions required for torsion plate design ..............................................198 D 3 Depiction of dimensions required for flexure plate design ..............................................199

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13 Abstract of Thesis Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Engineering ALTERNATIVE SUPPORT SYSTEMS FOR CANTILEVER SIGNAL/SIGN STRUCTURES By Kathryn L. Jenner May 2010 Chair: Ronald A. Cook Major: Civil Engineering During the 2004 hurricane season, several anchor embedment failures of the support structures of cantilever signal/sign structures occurred. A previous research program determined the cause of these failures was by concrete breakout due to shear on the anc hors directed parallel to the edge of the foundation. The purpose of the current research program was to take the knowledge obtained on the previous research program and identify a suitable alternative support structure without the use of anchor bolts. Aft er a literature review and experimental testing, it was determined that an embedded pipe with welded plates was a suitable alternative support structure. The torsion could be adequately transferred to the support structure concrete through the vertical tor sional plates and the flexure could be adequately transferred to the concrete through the welded annular plate on the bottom of the pipe. Furthermore, it was determined that the alternative selected was not only a viable alternative to the anchor bolt syst em, but it had greater strength than the anchor bolt system. The test specimen s were designed to fail by concrete breakout originating from the torsional and flexural plates. The rest of the testing apparatus was designed to preclude failure. The results o f the testing indicated that the concrete breakout was the failure mode for the embedded pipe and plate configuration and that the concrete breakout strength could be

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14 accurately predicted using modified equations for concrete breakout from ACI 31808 Appendix D. The results of these test s led to the development of guidelines for the design of the embedded pipe and plate configuration. Recommendations for future testing include an alternative base connection that precludes the use of annular plates

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15 CHAPTER 1 INTRODUCTION This project is in response to the failures of several cantilever sign structure foundations in Florida during the 2004 hurricane season ( See Figure 11 and Figure 12 ). The initial research program resulting from these failures was completed in August 2007 and is Florida Department of Transportation (FDOT) Report No. BD545 RPWO #54, Anchor Embedment Requirements for Signal/Sign Structures (1) The objective of the initial project was to determine the cause of failure of the foundations and to recommend both design procedures and retrofit options. It was determined that torsional loading on the anchor bolt group in the foundation wa s the most likely cause of the failure s Design recommendations for torsional loading on the anchor group and recommendations for a retrofit are included in the project report (1) The initial project also provided recommendations for potential alternative foundation systems. The primary objective of this research project was to identify alternative support structure designs without anchor bolts that will be better equipp ed to handle transfer of the torsional load to the concrete than the current anchor bolt design and then to conduct an experimental investigation and develop design guidelines for the identified alternative support structure In order to complete the objective of this research program, a thorough i nvestigation of alternative support structures used in other structural applications was completed The findings of this investigation as well as the recommendations of FDOT Report BD545 RPWO #54 were used as the groundwork for the experimental investigation and design guidelines for the identified alternative support structure

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16 Figure 11. Failed cantilever sign structure(1) Figure 12. Failed foundation during post failure excavation(1)

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17 CHAPTER 2 BACKGROUND The following sections cover the history of signal/sign anchor bolt foundations and present the various foundation systems recommended by FDOT Report BD545 RPWO #54 and alternatives used in other industries The current anchor bolt foundation system is revisited so that its part icular structural concerns can be identified and explored in alternative foundations The recommended foundations are analyzed for potential problems and benefits ; particularly on how they transfer load from the cantilevers monopole to the substructure. B ased on the information gathered, a recommended alternative is identified. 2.1 Current Anchor Bolt Foundation System During a recent survey (2) of state DOTs, an assessment of ty pical signal/sign foundations was conducted, par ticularly on the structural application of each foundat ion type and frequency of use (S ee Table 2 1 ) The information obtained from this survey shows that at present, reinforced cast in place foundations are the most common foundation types for overhead cantilever signs, with spread footing s the next most common foundation. The se most common foundation system s utilize anchor bolts to transfer torsional and flexural moments from the monopole to the support structure Figure 21 depicts how the torsional and flexural moments are transferred in the current anchor bolt design. AASHTO provides guidance in their Standard Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals ( Supports Specifications ) for the design of signal/sign supports (3) Many problems have been detected with the signal/sign support structures and the following will cover the history and problems associated with cantilever sig nal/signs and their support structures

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18 In 1994, the National Cooperative Highway Research Program ( NCHRP ) initiated Project 1710 at the University of Alabama at Birmingham (4) The scope of Project 1710 was to update all aspects, excluding vibration and fatigue, of the 1994 Supports Specifications (4) One element of the Supports Specifications that required immediate updating was the information on anchorage systems. The 1994 Supports Specifications information on anchor bolts was based on information obtained in the late 1960s and late 1970s (4) The updated anchor bolt information contained in Report 411 included an Appendix C which addressed minimum embedment length of headed cast in place anchor bolts, effect of edge distance, and the effect of spacing between anchor bolts (4) However, Appendix C of NCHRP Report 411 was not included in the 2001 Supports Specifications (2) A second phase of Project 1710 was initiated and published as NCHRP Report 494 in 2003. NCHRP Report 494 addressed additional updates to the Supports Specifications In NCHRP Report 494, further information is provided regarding anchorage to concrete. In addition to restating the information in Appendix C of NCHRP Report 411, NCHRP Report 494 provided a simplified design method for design of anchorage to concrete based on the then recently added Appendix D to ACI 31802 (2) The simplified design method for anchorage required the following conditions be met (2) : Anchor bolts be hooked or headed Foundations have vertical reinforcing steel and vertical confinement, with anchor bolts placed inside of the reinforcement Foundation reinforcing steel is uncoated If hooked anchor bolts are used, the length of the hook is at least 4.5 times the anchor bolt diameter The sim plified design method would design the diameter and bearing area of a headed anchor or the required anchor bolt diameter of a hooked anchor as well as the bolt length so that the failure plane would intersect the foundations reinforcing steel below the point at which the

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19 reinforcing steel is fully developed (2) The transfer of flexural moment is thoroughly addressed in the simplified design method through its treatment of tension. While the simplified method does well to addre ss anchor bearing on concrete, it makes the assumption that if confining reinforcement is provided, failure by concrete breakout and concrete side face blowout can be prevented (2) It also assumes that the shear force will not control because of the greater flexural moment. The se simplified design guidelines have not been included in the Support Structures However, the information obtained on anchor bolts by the FDOT under contract number BD545 RPWO #54 entitled Anchor Embedment Requirements for Signal/Sign Structures indicates that concrete breakout is a problem even if confining reinforcement is provided. The reason for the report was several cantilever support structure failures in Florida during the 2004 hurricane se ason ( See Figure 11 and Figure 12 ). The project predicted that the reason f or the failure of the cantilever signal/sign foundations was the hurricane wind loads applied excessive torsional force on the foundation. The torsional force could be resolved into shear force acting on the anchors parallel to the edge of the foundation ( See Figure 21). The shear force acting parallel to the edge was causing an anchor break out phenomena that is described in Section D.5.2 of ACI 31808 (5) Testing confirmed the prediction and a n evaluation guideline as well as a CFRP wrap retrofi t design guideline were detailed in the report. Clearly, the information gathered on the present system shows a need to rethink the design where anchors are concerned While the NCHRP Reports are designed to modify the Supports Specifications for the current anchor bolt design, t he purpose for this re search project is to identify an alternative method of transferring torsional and flexural m oments from the monopole to the concrete shaft other than through an anchor bolt connection.

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20 The main concern addressed in this research project is the failure of concrete due to shear load on the anchor bolts parallel to the edge resulting from torsion on the anchor group. Therefore, a viable alternative will be one that avoids transferring shear through anchor bolts O ther concerns that have been identified are design practice and construction related. While these concerns are not the main objective of t his research project, a new design may address these problems. The concern with fatigue has also been identified and is addressed in other research projects and is not in the scope of this project (6; 7) Recommendatio ns for future testing regarding f atigue concerns w ill be addressed in Chapter 6. 2.2 Alternative Foundation Systems The following alternatives are based upon the recommendations of the FDOT Report BD545 RPWO #54 (1) There are three cast in place concrete foundation alternatives and a drilled helical pipe alternative recommended from FDOT Report BD545 RPWO #54. Also included in this section is an embedded tapered section that was not included in the previous report but has been used in other DOT applications. 2.2.1 Ste el Pipes with Plates Welded at Four Locations This foundation system would use an embedded pipe with stiffener plates. Figure 22 shows the configuration of this system (1). The stiffener plates will be attached symmetrically around the shaft of the steel pipe. The purpose of the stiffener plates would be to provide for the transfer of torsional loading between the s teel pipe and the concrete by bearing on the concrete during twisting. The installation of this foundation would be relatively simple A fter excavation for the concrete foundation, a reinforcement cage would be lowered into the excavation and aligned properly The steel pipe and plate assembly would be lowered into the excavation and aligned. The concrete would then be poured into the excavation. T he n the superstructure would be

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21 erected on top of the foundation (8) The superst ructure could be aligned and leveled using a leveling nut detail shown in Figure 2 3. This connection would also eliminate problems with grout installation because none would be required. As mentioned earlier, t he vertical torsional plates would act similar to an anchor group for transferring load to the foundation. Figure 22 shows the possible force configuration that would be acting on the foundation and how the foundation would resist the forces Option A has an annular plate welded to the bottom of the embedded pipe and plate section while option B does not. The purpose of the annular plate is to provide a stiff member to resist the bending moment induced on the foundation. If the pla te were not a part of the configuration, then the pipe would likely resist the bending by bearing on the concrete, creating a potential problem with buckling of the pipe. As the biaxial moment acts on the foundation with the annular plate, it will induce a tensile reaction on one part of the concrete foundation and a compressive reaction on the opposite side, see Figure 22. The shear load will induce a distributed loa d on the sides of the foundation. The axial load will be distributed throughout the foundation by the annular plate. The torsional load will cause the stiffener plates to transfer the load as a shear force directed parallel to the edge of the concrete simi lar to an anchor loaded in shear parallel to the edge and bear on the concrete 2.2.2 Geometric Hollow Section This foundation would use a n embedded geometric hollow section rather than a steel pipe. Figure 24 shows the configuration of this system (1) The purpose of the geometric shape would be to create additional torsional resistance through the geometry of the shap e. The installation of this foundat ion would be very similar to the method mentioned for the embedded pipe and plate section

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22 The geometric shape of the pipe would act as the way to transfer the load from the steel monopole to the concrete. The concrete w ould be able to resist the torsional rotation of the pipe embedded in the foundation through the geometric advantages of the section The shear force wou ld cause the concrete to resist as a distributed load The moment would induce axial resistance. Figure 24 (b) shows the force configuration acting on the foundation and how it would resist the force by bearing on the concrete. 2.2.3 Pipe with Welded Studs In this opt ion, the steel pipe would be welded with symmetrically oriented rows of steel studs through the depth of the foundation. The purpose of the studs would be to provide resistance to both flexural and torsional loading The installation of this foundation wou ld be the sam e as both the embedded pipe and plates and the embedded geometric hollow section foundations. The welded studs would transfer the shear, flexure, and torsion from the steel superstructure to the concrete. All of the torsional and bending force s can be resolved into shear s on the studs at their various angles of loading. The studs w ould resist the shear by bearing on the concrete. Figure 25 shows the force configuration acting on the foundation as well as the resistive bearing forces from the concrete. 2.2.4 Helical Pipes This option would c all for the helical pipes to be screwed directly into the soil. This alternative provides the benefit of removing concrete as a consideration in the design. See Figure 26 for the configuration of this foundation. The geometry of the pipe and the strength of the soil itself would provide the torsional resistance required in the design. The pipes would need to be first protected against corrosion and then screwed into the soil

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23 One possible drawback to this alternative would be that t he helical pil es would require frequent field inspections to ensure that the soil is not failing. The helical piles would not be an ideal option for Florida because of the prevalent poor soil conditions Also, t he helical piles would be highly susceptible to corrosion because of the direct contact with the soil and possibl e direct contact with the water table. In this foundation system, the load would not be transferred from the steel to the concrete, but rather directly from the steel to the soil. Therefore a thorough geotechnical assessment would be required before design could begin. Because of this, it would be very difficult to present standard design guidelines for this option. 2.2.5 Embedded Geometric Tapered Section In this option, a geometric tapered section woul d be embedded into the drilled shaft ( S ee Figure 27 ) The purpose of the geometric shape would be to create additional torsional resistance through the geometric qualities of the shape. This foundation would require similar construction methods as the other cast in place options. The geometric ally varied shape of the tapered section would act as the way to transfer the load from the steel superstructure to the concrete. The concrete would be able to resist the twisting motion of the pipe embedded in the foundation through the geometry of the section. The shear force would cause the concrete to resist by bearing on the pipe in a distributed load The moment would induce axial resistance. One problem associated with this configuration is the avail ability of large tapered sections to be embedded in the foundation. The large tapered sections can be costly and difficult to find, limiting the practicality of this option. 2.3 Alternative Foundations from Other Industries An investigation into transmission line foundations, cellular tower foundations, wind turbine foundations, and large advertising sign foundations was completed. While investigating these fields it became apparent that despite the similarities in foundation requirements, the large

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24 torsion experienced by cantilever sign/signal foundations is not typically present in other industries and is not designed for. Because of this, the other industries alternatives would most likely not be viable for the cantilever sign and signal applications. The following section will describe what was found in these other industries. 2.3.1 Transmission Line Foundations An investigation into transmission line foundations showed that they often use cast in place concrete designs that are similar to the current an chor bolt design, using anchor bolts to connect the superstructure to the foundation ; see Figure 28c (9) The other cast in place designs, Figure 28a, Figure 28b are disparate from the current anchor bolt design. However, these are not viable alternative options because they are typically exposed to primarily axial and shear lo ads The sizes of the members make direct embedment a more suitable option for their foundations than a cant ilever sign/signal foundation. See Figure 29 for the loading that transmission line foundations are subject to (9) This loading pattern is similar, but not the same as the loading that cantilever sign/signal foundations are subject to. The torsional load that a cantilever superstructur e induces on a foundation creates additional concerns for trans ferring load to the foundation that these foundations cannot address. Other alternatives investigated in the transmission line industry seem unsuitable for sign/signal foundations because of construction sequencing, cost, and most importantly because they are unlikely to successfully transfer the torsional loading a sign/signal superstructure is likely to induce. The following are examples of unsuitable alternatives found in the transmission line industry : Drille d concrete piles, see Figure 210 (9) Prestressed anchors Grou ted soil anchors

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25 Drilled concrete piles are similar to the current anchor bolt design with the difference being that the guys are embedded in the cast in place fo undation instead of anchor bolts ( See Figure 210) These foundations handle axial, shear, and biaxial moments by transferring the loading from the embedded guys to th e concrete (9) However, because a transmission line tower is supported by multiple legs, minimal torsional forces are present in each drilled concrete pile. Even the H structures and single pole structures do not introduce much torsional force into the foundation because there is not a sufficient moment arm to produce significant torsional force. Figure 211 demonstrates the typical stru ctural configurations of a lattice tower, H structure, and single pole structure as well as a cantilever sign/signal structure (9) Prestressed and grouted soil anchors are typically not suitable to handle torsional load. As described in the I nstitute for E lectrical and E lectronics E ngineers (IEEE) Guide for Transmission Structure Foundation and Testing, anchors are primarily used to provide resistance to tensile forces (9) Prestressed anchors are typically expensive and should not be used in soils with time dependent compressibility (9) These factors make them typically unsuitable to use for cantilever sign/signal structures. See Figure 212 and Figure 2 13 for prestressed and grouted soil anchor configurations, respectively. Grouted soil anchors are designed to transfer uplift or tensile loads from the superstructure directly to the soil (9) They do this through frictional resistance between the grout and soil, as well as through the end bearing strength from the increased dia meter at the end of the anchor (9) However, the anchors do not provide much torsional resistance because of their smooth geometry.

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26 Despite the fact that these are viable alternatives in the field of transmission line foundations, these are generally not preferable options for sign and signal foundation systems. T he fact that sign and signal installations are sequenced at the end of highway construction make piles and anchors undesirable options By the time the contractor is installing signs and signals, most of the large pile driving equipment has been moved off the construction site and would create additional expens e for the contractor. Time and expense are also reasons why these options are not preferred. Prestressed anchors and grouted soil anchors require geotechnical expertise as well as significant geotechnical analysis of the area and would need to be designed for individual projects which can be more costly It would be difficult to produce a standard for these options. 2.3.2 Wind Turbine Foundations The search into wind turbine foundations was initially promising, being that they are required to handle significant amounts of lateral force from the wind (10) However, the torsion experienced by a wind turbine is not significant because there is a limited moment arm. Of greater con cern for a wind turbine is biaxial moments. Thus, t he three primary designs for a monopole wind turbine that were specified included a mat foundation, a pad and pier foundation, and a pier foundation, all of which utilize anchor bolts to connect the supers tructure to the foundation (11) There were guyed tower options as well, but these were not explored thoroughly because of their irrelevance to this projects application and their similarity to the transmission line industrys guyed tower foundations. The mat foundation, found in Figure 214, has several elements that make it unsuitable The primary fault with this option is that it uses anchor bolts, which is the purpose of this research project to eliminate. A mat foundation is also not suitable for the significant loads that a

PAGE 27

27 cantilever sign/signal structure will induce on a foundation. The uplift that is created by the cantilever structure will necessitate a deeper foundation. The pad and pier foundation, found in Figure 215 and the pier alone foundations are similar to the current anchor bolt design. They are cast in place concrete foundations with a monopole attached to the foundation by anchor bolts The pad and pier foundation is the same as the current anchor bolt design. The se options do not hold any potential for a new design because they are the same as the current anchor bolt design. The loading configuration on a wind turbine is similar to that of the transmission line structures. While the wind turbine and transmission l ine structures will exceed the height of the cantilever sign/signal structure, they do not have sufficient moment arms to create a torsion that is equivalent to the torsion experienced in a cantilever sign/signal structure. 2.3.3 Cellular Tower Foundations The cellular tower industry was consulted regarding alternative foundations particularly on which of the recommended designs from FDOT Report BD545 RPWO #54 seemed the most promising. Contact was made with Dave Hawkins, P.E. of Paul J. Ford & Co. from the Columbus, OH office. Hawkins is a member of the TIA TR14.7 committee which produces the TIA 222 Standard. The TIA 222 Standard governs the design criteria f or telecommunications tower structures. Paul J. Ford & Co. is a structural consulting firm that works in the design of communications towers and monopoles as well as transmission towers. Their specialization in this field made them an appropriate choice wi th which to discuss relevant alternatives. In a discussion with Hawkins, he stated that from his perspective, the steel pipe with welded plates or the geometric hollow section would be most preferred in his industry. The advantages he pointed out for the s teel pipe with welded plates are as follows: The stiffeners would act similarly to an anchor group

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28 Relatively easily cast in place No direct contact between the steel and soil, reducing corrosion issues Some possible problems with this configuration are mo stly construction related. If the substructure is not placed properly, then the superstructure would not align levelly. This is a concern with the current anchor bolt design, and will be a concern in most cast in place designs. The current anchor bolt meth od uses leveling nuts, as seen in Figure 23, to properly align the monopole with the foundation. The geometric hollow section is also a preferred option for the cel lular tower monopole industry because they currently use 12sided, 16 sided, and 18sided poles. Hawkins explained that any relevant research pertaining to these designs has not been conducted yet and would be very useful to the telecommunications industry. 2.3.4 Advertising Monopole Foundations For standards pertaining to monopole foundations in the advertising industry, the International Sign Association (ISA) was contacted. Contact was made with Bill Dundas, who is the ISAs Director of Technical Affairs Given FDOT Report BD545 RPWO #54, Dundas forwarded this information to the ISAs Mechanical and Structural Subcommittee to make comments and recommendations on preferences from the options selected in FDOT Report BD545 RPWO #54 as well as suggest any add itional designs. Based on the information gathered from ISAs Mechanical and Structural Subcommittee, the pipe with welded studs seemed to be a preferred option. The subcommittee commented that this detail had been used in larger pipes from 48 i nches to 96 inches in diameter. 2.4 Selection The purpose of the literature review and investigation into alternative support structures was to identify viable foundation alternatives on which to conduct an experimental program. The

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29 primary consideration taken into a ccount for the selection of the alternative support system was its ability to properly handle the loading configuration present in a cantilever sign/signal support system Constructability, time, and expense were taken into consideration though not fully explored. The foundation systems of other industries were investigate d and considered. Some of the least viable options were the drilled helical pipes, the soil anchors, and the piles. These options would not only be expensive, they would likely not suffic iently handle the loading conditions encountered by the foundation of a cantilever sign/signal configuration. The cast in place options seemed most viable as they are the currently used design and seem to be preferred by industry professionals. They can sufficiently handle the loading conditions, are less expensive than other options, and can be easily constructed. While the investigation into other industries provid ed insight into how different industries are addressing issues with shear, biaxial bending, and axial load, they do not necessarily provide solutions to implementing a design to transfer torsional load from the steel to the concrete. The recommended cast i n place designs from FDOT Report BD545 RPWO #54 are the designs with the most potential for applications of sign/signal foundations (1) Therefore, the recommendation for potential design was the pipe with welded plates. The cl ear load path associated with this option makes it ideal to design for. Industry professionals found this option to be effective at transferring load and easy to design. This design holds potential for a wider range of connections from the foundation to th e monopole superstructure. Also, t his option seem ed to be potentially cost efficient and effective at transferring the load appropriately to the foundation.

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30 Table 2 1. Support structure foundation frequency of use(7) Structure ty pe Reinforced Cast In Place Drilled Shafts Unreinforced Cast In Place Drilled Shafts Steel Screw In Foundation Spread Footings Directly Embedded Overhead Cantilever Common None Rare Intermediate None Over Head Bridge Intermediate None Rare Intermediate None Road Side Sign Intermediate Rare Rare Rare Rare Street Light Poles Intermediate Rare Rare Rare Rare High Level Lighting Poles Common None None Rare None Traffic Signal Supports Common None None Rare Rare Span Wire Supports Intermediate None None Rare Rare Notation Common = 67100% of the states reporting use Intermediate = 34 66% of the states reporting use Rare = 1 33% of the states reporting use None = 0% of the states reporting use Figure 21. How torsional and flexural moments are transferred using anchor bolts(1) Flexure Resolved into Tension and Compression Torsion Resolved into Shear Parallel to the Edge Concrete Cracking Applied Torsion Applied Flexure

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31 Figure 22. Alternative foundation: steel pipe with four welded plates Figure 23. Leveling nut detail B Mz Vx My A Mz Vx My

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32 Figure 24. Alternate foundation: geometric hollow section Figure 25. Altern ate foundation: pipe with welded studs Mz Vx My B Mz Vx My A Mz My Vx

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33 Figure 26. Alternate foundation: helical pipes Figure 27. Alternate foundation: geometric tapered section

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34 Figure 28. Cast in place foundation for transmission lines Figure 29. Potential forces acting on a transmission line foundation Center of Rotation (CR) Z Y X P M V A Stub Angle Diagonal Member Pier CL Mat Diagonal Member Pier Mat Stub Angle B Anchor Bolt Stub Angle Base Plate C

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35 Figure 210. Drilled concrete piles for transmission lines Figure 211. Typical transmission line structures compared to a cantilever sign structure Lattice Tower Single Pole Structure H Structure Cantilever Sign Battered Shaft B ell Straight Shaft

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36 Figure 212. Prestressed soil anchor Figure 213. Grouted soil anchors Friction Anchor Belled Anchor Multi -Belled Anchor Unbonded Tendon Pressure Bulb Prestressed soil anchor

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37 Figure 214. Mat foundation for wind turbines Figure 215. Pad and pier foundations for wind turbines

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38 CHAPTER 3 DESIGN IMPLICATIONS Based on the literature review and investigation into other industries, the embedded pipe with welded plates (See Figure 22 ) was chosen as a suitable alternative to the anchor bolt design (See Figure 21) Design provisions f or determining the strength of this option and how the forces are transferred from the steel to the concrete are not available Therefore, some approximations must be made on how this new configuration will transfer the load The forces that were primarily transferred through the anchor bolts were the torsional moment and flexural moment. Each of these forces will need to be designed for and a failure mode predicted in order for the design to be feasible. 3.1 Design for Torsion The first parameter to consider is the torsional moment. One estimate is that the welded plates will act similarly to an anchor group when transferring force to the concrete. Assuming this is a valid hypothesis, it would be equally valid to assume that the failure of this foundation would be similar to that of an anchor group failure. Therefore, the concepts that will be explored in this section include viewing the foundation failure as a concrete breakout or concrete side face blowout (See Figure 32 ) 3.1.1 Equivalent Concrete Break o ut Strength in Shear One method used to estimate the torsional strength o f this section wa s to a ssume the failure would be similar to a modified concrete break out failure from shear applied parallel to the edge. In FDOT Report BD545 RPWO #54 it was determined that the previous failures experienced by the foundations were concrete break out failures from torsional loads applying shear paral lel to the edge on the anchor bolt group (S ee Figure 3 1) (1) It was because of this failure that the alternative support structures res earch project was initiated. Therefore, during the experiment it

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39 would be useful to determine the equivalent torsional strength from concrete breakout and design the rest of the test to preclude other failure modes. In order to calculate an estimated stren gth of the concrete breakout, the anchor breakout equations need to be modified to account for the differences between an anchor breakout and the pipe and plate breakout. An anchor breakout failure occurs at the surface of the concrete in which it is installed typically with a The embedded pipe and stiffener configuration would cause the stif feners to cause a similar break out failure cone, though not at the top of the shaft The breakout would occur where the plates are emb edded in the concrete. As a result of this expected concrete break out, the breakout surface would be considerably larger than t hat of a typical concrete break out for an anchor loaded in shear because it will create a breakout cone in both the top and bottom of the welded plate. Figure 3 2 depicts the differences between th e typical anchor concrete break out and the expected breakout caused by the welded plates. In order to quantify the difference in these breakout configurations, some manipulation of the governing equations for concrete breakout of an anchor loaded in shear from ACI 31808 Appendix D (5) will be required. First, the breakout strength of an anchor loaded in shear needs to be described T he basic breakout strength of a single anchor in cracked concrete loaded in shear perpendicular to an edge ( See Figure 33 ) is described in ACI 318 08 Equation D 24 and is shown below as Equation 31 (5) 5 1 1 2 07a c a a e bc f d d V ( 31) Where Vb = basic concrete breakout strength in shear of a single anchor in cracked concrete (lb.) e = load bearing length of anchor for shear (in.) da = outside diameter of anchor (in.) = 1.0 for normal weight concrete fc = specified compressive strength of concrete (psi)

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40 ca1 = distance from the center of an anchor shaft to the edge of concrete in one direction; taken in the direction of the applied shear (in.) The maximum length for e is limited to 8 da as delineated in ACI 31808 D6.2.2. The constant 7 from Equation 31 was determined from a 5% fractile with cracked concrete. T he constant 7 becomes a constant 13 for the mean breakout strength of a single anchor in uncracked concrete loaded in shear perpendicular to the edge The mean breakout strength is described in Equation 32, as shown below (12) 5 1 1 2 013a c a a e bc f dd V (3 2) ACI 318 08 (5) describes the nominal breakout strength of a n anchor loaded in shear perpendicular to the edge in Equation D 21 and is described below as Equation 3 3. Figure 34 depicts the projected concrete failure area of a single anchor in rectangular concrete Figure 35 depicts the projected concrete failure area of a single anchor in cylindrical concret e. An important distinction to note between the failure area of a single anchor in rectangular concrete and cylindrical concrete is the edge distance ca1. Equation 3 4 details how to calculate the value of ca1 for an anchor adjacent to a circular edge. b V h V c V ed Vco Vc b cV A A V, (3 3) Where Vcb = The nominal concrete breakout strength in shear of a single anchor (lb.) AVc = The projected area of the failure surface for a single or group of anchors, used to determine the shear strength (in2) AVc o = The projected concrete failure area of a single anchor, for calculation of strength in shear, if not limited by corner influences, spacing, or member thickness (in.2) = 4.5( ca1)2, based on an Fig ure 216) ed,V = The factor used to modify shear strength of anchors for edge effects, ACI 31808 Section D.6.2.6 c,,V = The factor used to modify shear strength of anchors based on presence or absence of cracks in concrete and presence or absence of supplementary reinfor cement, ACI 31808 Section D.6.2.7, accounted for in Equation 2 2

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41 h,V = The factor used to modify shear strength of anchors based on anchor location and effective length of anchor, ACI 31808 Section D.6.2.8 25 3 25 32 2 2 1 b b s b ar r r r c (3 4) Where ca1 = distance from the center of an anchor shaft to the edge of concrete in one direction; taken in the direction of the applied shear (in.) rb = The distance from the center of the cylindrical shaft to the center of the anchor bolt (in.) rs = The radius o f the cylindrical shaft (in.) As FDOT Report BD545 RPWO #54 determined, the failure loading on the foundations anchor group was torsion (1) This torsion can be resolved into shear forces acting parallel to an edge. ACI 31808 prescribes in section D6.2.1 that the nominal concrete breakout strength of a single anchor loaded in shear parallel to an edge shall be permitted to be twice the value of the shear force determined as Vcb, which assumes shear loading perpendicular to an edge. Now that the basic equations for concrete breakout due to shear on anchor bolts have been established, it is appropriate to address the changes in these equations to satisfy the differences between the anchor breakout and the expected experimental br eakout. The mean breakout strength of a single plate in shear acting perpendicular to the edge has been modified from Equation 32 to Equation 35 listed below by substituting the geometric qualities from the anchor bolt system to the appropriate geometric qualities of the embedded pipe and plate system.. 5 1 1 2 013a c p p e bc f t t V ( 35) Where Vb = basic concrete breakout strength in shear of a single plate in uncracked concrete (lb.) e = load bearing length of plate for shear (in.) tp = thickness of plate (in.) ca1 = distance from the center of the plate to the edge of concrete in one direction; taken in the direction of the applied shear (in.)

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42 The arrangement of the plates in this specific design does not allow them to be analyzed as a group because their break out failure cones do not overlap. Therefore, Equation 33 was utilized to determine the strength of a single plate. However, the Avcp, or the projected area of the breakout surface for a single plate, was modified from Avc to account for the differences in the breakout surface. Figure 36 depicts the area AVcp. Because the concrete breakout area for t he plate is much larger than that of the anchor bolt, the ratio of the plate breakout area to the anchor bolt breakout area will include the increase in break out strength for the plate due to the larger breakout area. There will be an increase in strength because it will take more force to cause a breakout on a larger volume of concrete. Equation 36 accounts for the additional strength of a concrete break out for the embedded plate because the ratio of AVcp to AVco will be greater than one as can be seen by comparing Figure 35 and Figure 3 6. Eq uation 36 displays the equation utilized to determine the concrete break out strength of a single plate. b V h V c V ed Vco Vcp bp cV A A V, ( 36) Where Vcb p = The nominal concrete breakout strength in shear of a single plate (lb.) AVc p = The projected area of the failure surface for a single plate, used to determine the shear strength (in2) =3.0ca1*(3.0 ca1 + lpl) AVc o = projected concrete failure area of a single anchor, for calculation of strength in shear, if not limited by corne r influences, spacing, or member thickness (in.2) = 4.5( ca1)2, based on an Fig ure 34) The contribution of each plate to the overall torsional strength of the embedded pipe ( Tcbp) is twice the expected breakout strength ( Vcbp) multiplied by the moment arm. It is twice the expected breakout strength because as mentioned earlier, the shear strength when loaded parallel to the edge of concrete is permitted to be twice that of the shear strength when loaded

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43 perpendicular to the edge of concrete and Equations 35 and 36 are for loading perpendicular to the edge of concrete. p cbp bp cnr V T 2 (3 7) Where Tcbp = The nominal torsional strength of the pedestal from concrete breakout (kipft) Vcb p = The nominal concrete breakout strength in shear of plate configuration where the plates are not acting as a group (lb.) n = The number of torsional plates in the configuration; the plates are not acting in a group rp = The radius of the pipe (in.) 3.1.2 Equivalent S ide Face Blowout Strength Another method to determine the torsional strength of the embedded pipe and plate section is to determine the available bearing strength of concrete for the embedded pipe and plate section The bearing strength was exp ected to be calculated similarly to the side face blowout strength of a headed anchor in tension. The side face blowout strength of a headed anchor in tension represents the bearing strength of the concrete at the head of the anchor. Figure 3 7 depicts the similarities in anticipated failure cones for the embedded pipe and plate section and the headed anchor configuration. The similarity in these failures shows that th ere requires little manipulation of the equation to determine the bearing strength for the embedded pipe and plate section ACI 318 08 Appendix D determines the nominal side face blowout strength of a headed anchor in tension ( See Figure 38) in Equation D 17 and is show n below as Equation 3 8. c brg a sbf A c N 1601 ( 38) Where Nsb = t he nominal concrete side face blowout strength of a single headed anchor in tension (lb.) ca1 = distance from the center of an anchor shaft to the edge of concrete in one direction; taken in the direction of the closest edge (in.) Abrg = bearing area of the head of anchor bolt (in.2)

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44 fc = specified compressive strength of concrete (psi) The constant 160 from Equation 3 8 was determined from a 5% fractile in cracked concrete and is used to determine the nominal strength. By removing the safety factor attached to the 5% fractile and the cracked concrete, the constant for the mean side face blowout strength of a single headed anchor in uncracked concrete loaded in tension is 200 (13) The mean side face blowout strength of a single headed anchor in uncracked concrete is described in Equation 39, as shown below. c brg a sbf A c N 2001 ( 39) The modifications necessary to Eq uation 39 to account for the embedded pipe and plate section was to substitute Abrg from the bearing area of the head of the anchor bolt to the bearing area of the plate and substitute the rectangular concretes edge distance ca1 to the cylindrical concretes edge distance ca1 (See Equation 3 4) The equivalent torsional strength was derived using Nsb and multiplying it by the number of plates and moment arm, which is equ ivalent to the radius of the pipe. See Equation 3 10 for how to calculate the torsional strength using Nsb. p sb sbnr N T (3 10) Where Tsb = The nominal torsional strength of the concrete pedestal from side face blowout (kip ft) Nsb = The nominal concrete side face blowout strength of a single plate in tension (lb.) n = The number of torsional plates in the configuration rp = The radius of the embedded pipe (in.) 3.2 Design for Flexure The next parameter to be designed for is flexure. One method of handling flexure would be to weld an annular plate to the bottom of the pipe. The plate would be able to resist the tensile and compressive for ces induced by the flexure by bearing on the concrete. This failure would

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45 also produce a concrete break out or side face blowout that can also be compared to an anchor bolt failure. 3.2.1 Equivalent Concrete Breakout Strength in Shear One method of hypothesizing the predicted behavior of the embedded section would be to treat it as a typical annular base plate with anchor bolts. When analyzing flexure on this setup, the flexure can be resolved into a compressive force on one side of the plate and a tensile force on the other side of the flexural plate ( See Figure 310). The resolved forces can be viewed to act in one of two ways: shear parallel to an edge and an equivalent bearing pressure causing side face blowout In this section the hypothetical failure mode associated with shear parallel to the edge will be discussed. As shown in Figure 310 the flexural moment can be resolved into a tension and compression acting on opposite si des of the plate. Another way of looking at the tension and compression forces would be to rotate the foundation 90 degrees to more clearly see it as sh ear acting parallel to an edge ( See Figure 311). These shears will create a breakout failure similar to that experienced during torsional loading on the welded plates. Modifying Equation 3 2 to account for the differences in the anchor bolt configuration and the embedde d pipe and plate c onfiguration yields Equation 3 11, shown below. 5 1 1 2 013a c fp fp e bfpc f b t V (3 11) Where Vb fp = the basic concrete breakout strength in shear of one side of a flexural plate in cracked concrete (lb.) e = the equivalent bearing length of the annular plate, taken conservatively as 1/8 of the circumference of the centerline of the plate (in.) tfp = the thickness of the annular plate (in.) bfp = the bearing width of the annular plate (in.) fc = specified compressive strength of concrete (psi)

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46 ca1 = the edge distance, taken from the center of the width of the plate to the nearest concrete edge (in.) Once the basic concrete breakout strength of one plate bearing area has been determined then the total shear breakout capacity can be determined using Equation 312. Equations 311 and 312 are used to determine the shear strength perpendicular to an edge. To determine the shear strength parallel to an edge, the perpendicular shear strengths obtained need to be doubled. See Figure 3 12 for a visual representatio n of the values in Equations 3 11 and 312. bfp V h V c Ved Vco Vcp bfp cV A A V, (3 12) Where Vcb fp = The nominal concrete breakout strength in shear of plate configuration where the plate bearing areas are not acting as a group (lb.) AVc fp = The projected area of the failure surface for a single bearing location on the plate, used to determine the shear strength (in2) = ( 3.0ca1+ le) *(3.0ca1 + tfp) AVc o = projected concrete failure area of a single anchor, for calculation of strength in shear, if not limited by corner influences, spacing, or member thickness (in.2) = 4.5( ca1)2, based on an Fig ure 34) Using the value obtaine d from Equation 312, an equivalent flexural strength can be calculated using Equation 313. fp cbfp bfp cd V M 2 (3 13) Where Mcb fp = The nominal flexural concrete breakout strength in shea r of plate configuration where the plate bearing areas are not acting as a group (lb.) Vcbfp = The nominal concrete breakout strength in shear of plate configuration where the plate bearing areas are not acting as a group (lb.) dfp = The diameter of the centerline of the flexural plate (in.) 3.2.2 Equivalent Side Face Blowout Strength The other method to determine the flexural strength of the embedded pipe and plate section is to determine the available side face blowout strength of concrete for the embedded pipe and plate section. The side face blowout strength was expected to be calculated similarly to the side-

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47 face blowout strength of a headed anchor in tension, with the bearing area modified from the head of the anchor to the bearing area of the flexural plate. The similarity in these failures shows that there requires little manipulation of the equation to determine the side face blowout strength for the embedded pipe and plate section. Equation 3 8 seen earlier in the chapter describes the nominal side face blowout strength of a headed anchor in tension while Equation 39 describes the mean side face blowout strength of a headed anchor in tension. Equation 3 9 would be used to determine the strength for each bearing area on the flexural plate. Figure 313 illustrates the bearing area for one location on the flexural plate. The difference in Equation 39 for a headed anchor bolt a nd the flexural plate system would be that the Abrg would be the bearing area of the flexural plate rather than the headed anchor In order to quantify this, a recent study on tension and compression testing of signal/sign base plates utilizing anchor bolt s compared bearing areas for calculating the bearing strength of headed anchor bolts was looked into (14) The current method utilizes a bearing area equivalent to the head area. This was found to be a very conservative approach, with the field tests yielding more than double the strength predicted using the equivalent bearing area equivalent to the head area. The recommendation of the paper was to utilize the spacing between bolts and the entire width of the embedded template a s the bearing area (14) Based on this information, it would seem reasonable to utilize the same principles to estimate the bearing area of the plate. However, since there would be 4 bearing areas on the plate, it seems unreaso nable to assume that the bearing area would be one quarter of the plate area. In order to be conservative it was assumed that the bearing area would be one eighth of the plate area. See Figure 3 14 for an illustration of the bearing area comparison.

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48 By using this technique to calculate the bearing strength of the plate and using a moment arm of the diameter of the centerline of the plat e, an equivalent flexural strength can be computed. See Equation 314 below to determine the equivalent flexural strength from side face blowout. fp sb sbd N M (3 14) Where Msb = The nominal flexural strength of the concrete pedestal from side face blowout (kip ft) Nsb = The nominal concrete side face blowout strength of a single bearing area on the flexural plate in tension (lb.) rfp = The radius of the centerline diameter of the fl exural plate (in.) 3.3 Design Implications Summary By modifying the concrete breakout and bearing strength equations from ACI 31808, a reasonable estimate of the torsional and flexural strength of the embedded pipe and plate section could be calculated. The estimated torsional and flexural strengths of the embedded pipe and plate section were calculated as approximately twice that of the traditional anchor bolt setup.

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49 Figure 31. Concrete breakout of a n anchor caused by shear directed parallel to the edge for a cylindrical foundation Figure 32. Differences between concrete breakout failures for anchor bolts in shear and embedded pipe and plate section in torsion Figure 33. Concrete breakout formula for an anchor loaded in shear1 V b c a1 V b Concrete Edge

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50 Figure 34. Shear breakout of a single anchor in rectangular concrete Figure 35. Shear breakout for a single anchor in cylindrical concrete V b c a1 1.5c a1 1.5c a1 V b 1.5c a1 A Vco 1.5c a1 1.5c a1 1.5c a1 A Vco =1.5c a1 (1.5c a1 ) =4.5(c a1 ) 2 c a1 c a1 1.5c a1 35 35 1.5c a1 1.5c a1 1.5c a1 1.5c a1 1.5c a1 A Vco

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51 Figure 36. Determination of AVcp based on section 3.0c a1 +l pl V b c a1 l pl A Vcp = 3.0c a1 (3.0c a1 + l pl ) A Vcp 1.5c a1 1.5c a1 3.0c a1 +l pl 1.5c a1 1.5c a1 c a1

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52 Figure 37. Similarities of failure cones in side face blowout of a headed anchor in tension and the embedded pipe and plate section in torsion Figure 38. Concrete side face blowout equation for a headed anchor in tension c a1 N sb Concrete Edge

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53 Figure 39. Schematic of anticipated failure and bearing area of torsion plate Figure 310. Flexure resolved into a tension and compression on an anchor bolt system and the proposed system c a1 A brg

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54 Figure 311. The tensile and compressive forces seen as shears acting parallel to an edge Figure 312. Determination of AVcfp based on section 3.0c a1 +t fp 1.5c a1 1.5c a1 c a1 c a1 A Vcfp = (3.0c a1 +l e ) (3.0c a1 + t fp ) 3.0c a1 +t fp l e 1.5c a1 1.5c a1 A Vcp l e V bfp V bfp V t V c

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55 Figure 313. Illustration of bearing area on flexural plate for side face blowout calculations Figure 314. Flexural plate bearing area for side face blowout calculations 1/8 Bearing Area (Conservative) 1/4 Bearing Area (Not conservative) A brg N sbfp

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56 CHAPTER 4 DEVELOPMENT OF EXPER IMENTAL PROGRAM After the background investigation, it was determined that the embedded steel pipe with welded plates would be the alternative used to develop the experimental program. The experimental program for the initial testing would be similar to that conducted on FDOT Project BD545 RPWO #54, using a lever arm to create primarily to rsional loading on the foundation. The second test would induce both torsional and flexural loading on the alternative design. Based on the alternative identified from the background investigation, torsion from the attached member is transferred by bearing on the embedded plates. The flexure from the attached member is transferred by creating a tension and a compression on the embedded welded annular plate. A potential failure mode needed to be identified and a strength for this predicted failure mode quantified. The predicted torsional failure mode was a concrete break out failure caused by bearing on the welded plates would occur as shown in Figur e 4 1. Two possible methods of quantifying this were identified and are described in the previous chapter. One method to quantify the failure strength was to reference the equations from Appendix D of ACI 31808 regarding anchors loaded in shear parallel to an edge and modify them to account for the additional concrete breakout area encounte red by the plate configuration (5) Another potential way to determine the failure capacity of the embedded pipe and plate section was to consider the side face blowout strength of the concrete caused by the welded plates similar to that of a headed anchor loaded in tension. I n order to quantify this failure, the equations from Appendix D of ACI 31808 were modified to account for t he differences between the pipe and plate assembly and a headed anchor (5) Based on the quantified values from these potential failure modes, the rest of the test apparatus was designed to preclude other failure modes and determine the tested strength of the

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57 pipe and plate assembly in order to develop design guidelines. This chapter elaborates on the development of the experiment al test program. As a side note, in both torsion and flexure, the predicted concrete breakout strength was less than the predicted side face blowout strength. These strengths were utilized to determine the required strengths of the remainder of the test ap paratus. Therefore, if the nominal strength of a portion of the test design did not exceed the predicted side face blowout strength yet exceeded the predicted concrete breakout strength, it was deemed sufficient. 4.1 Description of Test Apparatus The test from FDOT Report BD545 RPWO #54 was designed to be a half size model of field conditions for testing at the Florida Department of Transportation (FDOT) Structures Research Center. Therefore, the starting point for this test was to design the concrete shaf t the same size as the half size model from the previous report. During design of the first test the concrete shaft was modified from the original half size design of a 30 diameter to a 26 diameter to reduce the capacity of the concrete shaft so that th e previously fabricated lever arm would be sufficient for the test. This process will be described in detail in the subsequent sections. The second test that was conducted for flexure and torsion was designed using the original half size design of a 30 d iameter. A schematic of the torsion test apparatus is shown in Figure 42. A schematic of the flexure and torsion test apparatus is shown in Figu re 4 3. The final design for the torsion test apparatus consisted of the following: A 26 diameter concrete shaft that extended 3 0 outward from the concrete block A 16 diameter steel pipe assembly with 4 welded 1 x 1 x 7 steel plates The 16 diameter embedded pipe assembly welded to a 24 diameter, 1 thick steel base plate with 12 1.75 diameter holes drilled for the anchor bolts to provide the connection this lever arm assembly an d the embedded pipe assembly A 16 diameter, 10 0 long steel pipe lever arm assembly

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58 Twelve 4.5 long, 1.5 diameter A490 bolts and associated nuts and washers to connect the lever arm assembly and the embedded pipe assembly A 6 0 x 10 0 x 2 6 rein forced concrete block to provide a fixed support at the base of the concrete shaft Two assemblies of C12x30 steel channels and plates to attach the block to the floor The final design for the torsion and flexure test apparatus consisted of the following: A 30 diameter concrete shaft that extended 3 0 outward from the concrete block A 16 diameter steel pipe assembly with 4 welded 1 x 1 x 7 steel plates and a welded 20 outside diameter annular plate A 16 diameter, 10 0 long steel pipe lever arm assembly A 16 diameter, 7 0 long steel extension pipe assembly The 16 diameter embedded pipe assembly was also welded to a 24 diameter, 1 thick steel base plate with 12 1.75 diameter holes drilled for bolts to provide the connection between this embedded pipe assembly and the lever arm assembly 124.5 long, 1.5 diameter A490 bolts and associated nuts and washers to connect the extension pipe assembly and the embedded pipe assembly An additional 124.5 long, 1.5 diameter A490 bolts and associated nuts and washers to connect the extension pipe assembly and the lever arm assembly A 6 0 x 10 0 x 2 6 reinforced concrete block to provide a fixed support at the base of the concrete shaft Two assemblies of C12x30 steel channels and plates to attach the block to the floor The basis for the selection of the concrete shaft s diameter was o ne half of the diameter of a typical field design. One problem that also needed to be addressed was to maintain the torsional strength of the concrete shaft below that of the previously fabricated lever arm assembly. Based on the quantified strength of the embedded pipe and plate assembly, the remaining components of the test apparatus were designed to preclude all failure modes other than the concrete breakout or sidefa ce blowout of the welded torsional plates and/or flexural plate.

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59 More detailed informat ion regarding the design of the components of the test apparatus is provided in the subsequent sections. Much of the design of the embedded pipe and plate apparatus and reinforced concrete shaft was performed using an iterative process. Therefore, the foll owing sections will be organized as chronologically as possible, though some information in later sections was necessary to design components in earlier sections. Figure 4 4, Figure 4 5, Figure 46, and Figure 47 provide more detailed drawings of the torsion test apparatus. The flexural test apparatus was very similar with the main differences being an inclusion of a flexural plate on the embedded sectio n and a flexural extension pipe on the testing assembly. Figure 48 shows a 3 D isometric view of the embedded section for the second test. For larger scale, dimen sioned drawings for both tests refer to Appendix A. Complete design calc ulations a re located in Appendix B 4.2 Embedded Pipe and Plate Design The embedded pipe and plate section s design was based upon the strength of the lever arm (s) and on the flexural and torsional strength requirements of the test procedure. The embedded pipe and plate section must be at least as strong as or stronger than the traditional anchor bolt design in order to be a viable alternative. The embedded pipe and plate section would be bolted to the lever arm assembly, which was designed in the previous experiment as an HSS 16x.500 with a 24 diameter annular plate. I t seemed beneficial to size the pipe and bas e plate the same as the lever arm assembly. Based on this configuration, the welded stiffener plates, welds, concrete breakout and side face blowout strengths were determined. 4.2.1 Concrete Breakout and Bearing Strength The f acet of the design that dictated the rest of the design was the predicted concrete breakout strength and side face blowout strength of the embedded pipe and plate apparatus. For

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60 design purposes, a concrete strength of 5500 psi was assumed. This value was adjusted for more accurate strength prediction when the average 28 day compressive strength of the concrete cylinders was obtained. By u sing Equation 3 7, the torsional breakout strength for the assembly was determined to be 249 kipft for the torsion test apparatus Similarly, by using Equation 310, the torsional side face blowout strength for the assembly was determined to be 390 kipft. See Figure 4 1 for the expected breakout configuration of the torsional test assembly The expected torsional breakout and side face blowout strengths of the torsional and flexural te st assembly were calculated similarly using Equations 37 and 310. The expected torsional breakout strength of t he torsion and flexure test assembly was 348 kipft while the expected torsional side face blowout strength of the second test assembly was 523 kipft By using Equations 3 13 and 314, the flexural breakout and side face blowout strengths could be determi ned. Equation 3 13 determined a flexural breakout strength of 218 kipft. Equation 314 determined a flexural side face blowout strength of 337 kipft. Of concern in the combined torsion and flexure test was the potential interaction between torsional and flexural breakout due to overlap in the breakout surfaces (See Figure 49). A linear interaction diagram between torsion and flexural strengths was produced to predict a testing failure load (See Figure 410) Because of the test arrangement, a 1 kip applied load would produce 9 kipft of torsional moment and 8 kipft of flexural m oment. Therefore if a completely linear interaction occurred then the maximum flexural moment would be 128 kipft and the maximum torsional moment would be 144 kipft. 4.2.2 Welded Stiffener Plates Design The starting point for the design of the welded stiffener plates was to determine their width and thickness. It was determined that a 1x1 plate would be approximately equivalent to an

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61 anchor bolt. The length of the plate was determined by the required 3/ 8 fillet weld length that corresponded to the resolved shear force acting on the plates, 93 kips, which was determined from the equivalent torsional concrete breakout strength of 249 kipft The required weld length was determined as 6. To be conservativ e the plates were designed to be 1x1x7. In order to be sure that the force would be transferred to the plates as predicted, it was necessary to ensure that the longitudinal reinforcement had enough length to be fully developed before the cone of the concrete breakout reached the longitudinal reinforcement. The longitudinal r einforcement was based upon that determined in FDOT Report BD545 RPWO #54 24 #4 bars evenly spaced. The development length was calculated using ACI 31808 12.2.3 and was determined to be approximately 8 (5) The breakout length above the 7 stiffener plate was determined to be approximately 5.6. Therefore, when the embedded pipe was placed at a depth of 24 in the concrete shaft and the welded plates were pla ced at the bottom of the pipe, enough concrete shaft length would be available for full development of the longitudinal reinforcement. 4.2.3 Annular Flexural Plate Design The annular flexural plate needed to be designed to have an adequate bearing area for the load to be transferred to the concrete. The welds needed to be designed to preclude failure from the applied flexure. Therefore, the starting point of the design of the annular plate was to use the same thickness as that used in the base plate, which was 1, to preclude yielding. The plate was designed to have a 20 outside diameter and a 16 inside diameter. The outside diameter was designed as 20 in order to allow for the concretes aggregate to be able to pass between the flexural plate and the reinforcement cage of the concrete shaft. The assumed bearing area, as described in the previous chapter, was 1/8 of the circumference of the centerline of the plate, or in this design 7, by the half the width of the plate, which was 2. This bearing area is considered conservative due to recent findings (14) The welding for the plate was determined to be the

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62 same as the previous designs base plate welds, or 3/8 fillet welds on the exterior and interior of the annular plate and pipe connection. 4.2.4 Annular Base Plate Design The annular base plate for the embedded pipe and plate was designed to align with the annular base plate of the lever arm apparatus. It was designed to have a 24 diameter, 1 thickness, with 121.75 diameter holes centered on the plate. Standard A490 1.5 diameter bolts were designed to replace the 1.5 diameter anchor bolts utilized in the previous design. The equivalent torsional bolt bearing strength and bolt shear were calculated as 2418 kipf t and 1272 kipft respectively, which greatly exceeds the concrete breakout and side face blowout strengths calculated earlier. The welding for the plate was determined to be the same as the previous design, or 3 /8 fillet welds on the exterior and interior of the annular plate and pipe connection. 4.2.5 Pipe Design The pipe was determined to be embedded in the foundation 24, which is approximately equivalent to the 26 embedment length of the anchor bolts in the previous design. In order to allow for the bolts to be fastened at the base plate, an additional 1.5 was included in the length. As stated earlier, the pipe was designed as an HSS 16x.500 with a yield strength of 42 kips/in2 an d an ultimate strength of 58 kips/in2. The torsional strength of an HSS 16x.500 pipe was determined using AISC 2005 Specification H3.1 as 359 kipft (15) This was a limiting factor on the size of the concrete shaft as will be explained in the subsequent section. Figure 411 shows the fabricated pipe and plate section. 4.3 Concrete S haft Design The design of t he concrete shaft was initially based on the same dimensions as the concrete shaft used in P roject BD545 RPWO #54. The reasoning behind this was to obtain comparable results to determine the benefits and drawbacks to the new design as compared to the anchor bolt

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63 design. The previous concrete shaft was based upon developing a test specim en approximately one half of the size of the foundation that was investigated in a site visit for that project (1) However, based on the 30 diameter of the concrete shaft used in the previous design, it became apparent that the calculated torsional strength of the embedded pipe and plate apparatus would exceed the torsional strength of the lever arm utilized in the previous test. Therefore, the concrete shaft diameter was reduced to 26 From there, the torsional and flexural capacity was determined using ACI 31808 requirements, taking care to prevent failure before the concrete breakout or bearing strength was encountered and exceeded. A concrete strength of 5500 psi was utilized in the calculations, which is the strength indi cated on FDOT standard drawings 4.3.1 Concrete S haft Diameter Design The starting point for the concrete shaft diameter was 30, the same as that of the previous project Using this concrete shaft diameter, the value of ca1 was determined to be approximately 5. The calculated equivalent torsional concrete breakout strength was determined to be 296 kipft The calculated equivalent torsional bearing strength was determined to be 446 kipft The torsional strength of the leve r arm pipe was calculated to be only 359 kipft which exceeds the concrete breakout strength and does not exceed the bearing strength. Since the estimated strength will likely lie between those values, the lever arm pipe does not provide enough strength. For the first test the concrete shaft diameter was reduced to 26 to decrease the concrete breakout and bearing strength to 212 kipft and 333 kipft respectively However, for the second test a 30 concrete shaft diameter was chosen because it was though t that the interaction of the flexural and torsional failure modes would reduce the overall strength of each failure mode and the increased value of ca 1 would be compensated for.

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64 4.3.2 Torsion Design The basic threshold torsional strength of the concrete shaft was calculated using ACI 31808 11.6.1(a) to be 18 kip ft (5) The threshold torsional strength does not take into account the reinforcement present in the concrete shaft and therefore will likely be exceeded. Therefore, the nominal torsional strength, which does take into account reinforcement, was used a s the design torsional strength. The cracking torsional strength was determined from ACI 31808 R11.6.1 as 73 kipft (5) Since the concrete breakout and side face blowout torsional strengths exceeded this value, it indicated that there would be torsional cracks in the concrete shaft before i t fails. In order to calculate the nominal torsional strength of the concrete shaft the reinforcement needed to be specified. The starting point was derived from the previous design, with the transverse hoop steel being comprised of #3 bars spaced at 2.5. However, it became clear that the torsional streng th with this reinforcement scheme, 191 kipft, was insufficient to exceed the concrete breakout or bearing strength of the section, 212 kipft or 333 kip ft respectively. Therefore, the hoop steel size was increased to #4 bars and the spacing decreased to 2 to yield a nom inal torsional strength of 426 kipft, which exceeded the concrete breakout strength of the section and almost attained the bearing strength of the section. This wa s sufficient because it was estimated that the experimental strength would lie somewhere between these values. 4.3.3 Longitudinal and Transverse Reinforcement As was previously stated, the hoop steel for the torsion test was comprised of #4 bars spaced at 2. The hoop steel for the torsion and flexure test was comprised of #3 bars spaced at 2.5. The hoop steel s center to center diameter was determined to be 22 for the torsion test and 27 for the torsion and flexure test The splice length of the hoop steel was determined using ACI 31808 12.2.3 to be approximately 16 (5)

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65 The longitudinal steel layout for the torsion test comprised of 24 #4 bars evenly spaced around a 21 center to center diameter. The longitudinal steel layout for the torsion and flexure test comprised of 24 #4 bars evenly spaced around a 26 center to center diameter. The longitudinal steel required a 6 hook and a development length of 8 into the concrete block. The longitudinal bars extended 27 into the concrete block for ease of construction, which exceeded the development length. 4.3.4 Flexure Design The flexural capacity of the concrete shaft was also deemed necessary because the setup of the test imposed both torsion and flexure on the concrete shaft T he longitudinal bars detailed in the previous section would provide the flexural reinforcement for the concrete shaft The ACI stress block method detailed in ACI 31808 Chapter 10 (5) was utilized to determine the flexural str ength. It was determined that the flexural strengt h of the torsion tests section was 245 kipft and the torsion and flexure tests section was 296 kipft The anticipated maximum applied flexure for the first test was 125 kipft The anticipated maximum applied flexure for the second test would be transferred to the concrete by the flexural plate on the bottom of the pipe. 4.4 Concrete Block and Tie Down Design For both tests, t he concrete block was desi gned to provide a fixed base for the concrete shaft The design of the reinforcement was based upon a strut andtie model design outlined in ACI 318 08 Appendix A (5) The reinforcement was also analyzed using the beam theory to be sure that the reinforcement was adequate in sh ear and flexure. The information obtained from these approaches determined that 6 #8 bars, each with a 12 in. hook on each end would be sufficient. 3 of the #8 bars would be placed on the top of the block and the remaining 3 #8 bars would be placed on the bottom of the block. A dditional reinforcement included two cages of #4 bars placed in the blocks front and back faces. These additional reinforcement cages would meet

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66 the supplementary reinforcement requirements. Using this reinforcement arrangement, the concrete block was determined to be a fixed base for the concrete shaft The tie down was designed to be comprised of two channels connected by welded plates. The channels individually and as a channel assembly were designed for flexure and local buckling as specified in AISC 2005 (15) Each channel assemblys resistance was required to not exceed the floor capacity of 100 kips on either end, or 200 kips total. The bearing capacity of the concrete at the point of contact betwee n the channel assembly and the concrete block was also checked to ensure that the loading from the channel would not cause the concrete to fail in that region. 4.5 Instrumentation To successfully obtain data from the experimental program, a plan for instr umentation needed to be designed. The rotational stiffness of the concrete shaft was necessary to understand the behavior of the newly designed concrete shaft To obtain this information, a system of linear variable displacement transducers (LVDTs) would n eed to be arranged. To accurately determine the rotational stiffness of the concrete shaft a system with 11 LVDTs was arranged. The arrangement of the LVDTs is detailed in Figure 412 through Figure 415. There will be one LVDT 6 from the point of applied force. There will be 4 LVDTs on the base plate, 3 measuring vertical displacement, 1 measuring horizontal displacement (See Figure 412). The measurement from D4 (as seen in Figure 4 12) will measure the horizontal displacement of the base plate. The rotation of the base plate was calculated using Equation 4 1. gageD D D R3 1 1tan ( 41) Where R = base plate rotation (rad) D1 = displacement of LVDT D1 (in.)

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67 D3 = displacement of LVDT D3 (in.) Dgage = distance between LVDTs D1 and D3 (in.) Figure 413 shows the arrangement of the LVDTs on the top of the concrete shaft Figure 414 shows the arrangement of the LVDTs on the bottom of the concrete shaft where the concrete shaft meets the block. The purpose of these LVDTs was to measure the rotation of the concrete shaft relative to the base plate. Figure 415 shows the LVDT 6 from the load location. 4.6 Summary of Torsion Design To summarize, the previous sections describe the design of the various components of both experimental program s For the torsion test, the ke y element of the design that dictated the rest of the design was the concrete shaft The concrete breakout or bearing strength of the shaft with the embedded pipe and plate apparatus was the ultimate strength of the entire system. All other components of t he system were designed to preclude failure from these elements. This way the experimental strength of the embedded pipe and plate system could be observed and appropriate design guidelines could be written to detail the strength of the new system. Appendi x A shows detailed and dimensioned drawings of the testing apparatus. Appendix B shows detailed calculations for the test apparatus. The most critical components of the design were the embedded pipe and plate apparatus and the reinforced concrete shaft. As long as the components of the concrete shaft and embedded pipe and plate section exceeded that of the equivalent torsional concrete breakout strength then the design was sufficient. Table 4 1, shown below, summarizes the essential design components, their equivalent torsional strengths, whether the strengths are mean or nominal, and their ratio compared to the concrete breakout strength.

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68 4.7 Summary of Torsion and Flexure Design For the torsion and flexure test, once again the key element of the design that dictated the rest of the design was the concrete shaft. The concrete breakout or bearing strength of the shaft with the embedded pipe and plat e apparatus in torsion and flexure was the ultimate strength of the entire system. All other components of the system were designed to preclude failure from these elements. Appendix A shows detailed and dimensioned drawings of the testing apparatus. Appendix B shows detailed calculations for the test apparatus. Table 4 2, shown below, summarizes the essential design components, their equivalent torsional and flexural strengths, whether the strengths are mean or nominal, and their ratio compared to the interac tion torsional and flexural strength values .

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69 Figure 41. Predicted concrete breakout failure Figure 42. Schematic of torsion test specimen

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70 Figure 43. Schematic of torsion and flexure test specimen Figure 44. Front view of torsion test setup Lever arm Applied load Channel tie down Concrete block with reinforcement

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71 Figure 45. Top view of torsion test setup Figure 46. Side view of torsion test setup Channel tie down Lever arm Concrete shaft Embedded pipe and plate apparatus Concrete block with reinforcement Lever arm Channel tie down Concrete shaft Embedded pipe and plate apparatus Concrete block with reinforcement

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72 Figure 47. Views of the embedded torsion pipe section Figure 48. Isometric view of embedded torsion and flexural pipe section for the second test Embedded pipe Welded plate Welded annular plate Bolt hole

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73 Figure 49. Breakout overlap of the torsional and flexural breakouts Figure 410. Interaction between torsion and flexure for concrete breakout Overlapping breakout area Torsional plate breakout area Flexural plate breakout area

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74 Figure 411. Fabricated pipe and plate apparatus Figure 412. Arrangement of the LVDTs on base plate

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75 Figure 413. Arrangement of the LVDTs on the top of the concrete shaft Figure 414. Arrangement of the LVDTs on the bottom of the concrete shaft Figure 415. Arrangement of the LVDTs at the load location

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76 Table 4 1. Summary of pertinent design strengths for torsion test with 5500 psi concrete Failure Mode Capacity Mean or Nominal? Predicted Load Ratio of Failure Capacities Embedded Pipe and Stiffeners Equivalent Torsion from Shear Parallel to an Edge 249 kip ft Mean 27.67 1.00 Equivalent Torsion from Side Face Blowout 391 kip ft Mean 43.44 1.57 Circular Shaft 26" Torsion 373 kip ft Nominal 41.44 1.50 Flexure 252 kip ft Nominal 126.00 2.02 "Superstructure" Pipes 16" x .5" Torsion 359 kip ft Nominal 39.89 1.44 Flexure 392 kip ft Nominal 196.00 3.14 Table 4 2. Summary of pertinent design strengths for torsion and flexure test with 5500 psi concrete Failure Mode Capacity Mean or Nominal? Predicted Load Ratio of Failure Capacities Embedded Pipe and Stiffeners Equivalent Torsion from Shear Parallel to an Edge 348 kip ft Mean 38.67 2.42 Equivalent Torsion from Side Face Blowout 523 kip ft Mean 58.11 3.63 Equivalent Flexure from Shear Parallel to an Edge 218 kip ft Mean 27.25 1.70 Equivalent Flexure from Side Face Blowout 337 kipft Mean 42.13 2.63 Anticipated Interaction Torsional Strength 144 kipft 16.00 1.00 Flexural Strength 128 kipft 16.00 1.00 Circular Shaft 30 Torsion 253 kipft Nominal 28.11 1.76 Flexure 296 kipft Nominal 37.00 2.31 "Superstructure" Pipes 16" x .5" Torsion 359 kipft Nominal 39.89 2.49 Flexure 392 kipft Nominal 49.00 3.06

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77 CHAPTER 5 EXPERIMENTAL TEST RESULTS Two separate tests were conducted on different specimens. The first test was conducted to determine the viability of the alternative chosen in torsion only. This was determined by the comparison of the experimental strength to an equivalent anchor bolt assemblys calculated strength (See Appendix A) The second test was conducted to determine the viability of the alternative chosen in torsion and flexure and to determine the interaction of the torsion and flexure failure modes. This also was determined by comparing the experimental strength of the system to an equivalent anchor bolt assemblys calculated strength (See Appendix A ) 5.1 Torsion Test 5.1.1 Behavior of Specimen During Testing The first test comprising of primarily torsional loading was conducted on September 23, 2009 at the Florida Department of Transportation Structures Research Center. The test specimen was gradually loaded and the formation of cracks on the surface of the concrete was monitored. At approximately 76.5 kipft, the bolts in the base connection slipped. This was because 1.5 diameter bolts were used in 1.75 diameter bolt holes. Approximately 1/4 slip occurred. This can be seen in Figure 5 1. At approximately 85.5 kipft, torsional cracks began to form on the concrete shaft (See Figur e 5 2) At approximately 153 kipft, concrete breakout failure cracks began to form on the concrete shaft while the torsional cracks continued to widen (See Figure 53) At approximately 191 kipft, the concrete breakout failure cracks began to widen noticeably (See Figure 54) The foundation continued to be loaded until the specimen stopped taking on more load. The torsion load peaked at approximately 250 kip ft (See

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78 Figure 55 ) At failure the foundation displayed the predicted breakout cone extending into the foundation. As intended, the rest of the test specimen did not fail before the predicted breakout fa ilure occurred. 5.1.2 Summary of LVDT Test Results Data was reduced to formulate an applied torsion versus plate rotation plot. The plot shows that the embedded pipe and plate configuration ceased taking on additional load at 250 kipft after the concrete breakout failure due to shear applied parallel to the edge resulting from the applied torsion. The cylinder tests indicated that the compressive strength of concrete on the day of testing was 5550 psi. When the predictions with the 28 day concrete strength were made, the concrete breakout predicted 250 kip ft and the side face blowout method predicted 392 kipft. The applied torsion versus plate rotation plot also shows a change in slope when the specimen experienced a redistribution of load due to bolt sl ippage, formation of various cracks, and widening of cracks. See Figure 56 for the graph of applied torsion versus plate rotation. LVDT information was gathered at the front base plate, the face of the shaft, and the rear of the shaft. As shown in Figure 57, the base plate rotated significantly more than the face of the shaft. This can be attributed to the fact that bolt slippage occurred, resulting in approximately 1/4 additional rotation, which can contribute approximately 1.25 of additional rotation for the base plate at failure The rear of the shaft was designed to be a fixed support and proved to be so until failure occurred and the entire shaft rotated. 5.1.3 Summary of Torsion Test The alternative support structure proved effective at transferring t orsional load during the initial testing. It was determined that the modified anchor breakout equations accurately predicted the behavi or and strength of the failure within 0.16% error. The test specimen had a cone shaped blowout failure within the foundat ion at the approximate location of the torsional

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79 plates. It was also determined that the alternative tested had approximately twice the strength of the calculated strength of an equivalent anchor bolt system (See Appendix B) For more details on the calcul ated strength of an equivalent anchor bolt system compared to the test apparatus strength, see the test apparatus calculations in Appendix B 5.2 Torsion and Flexure Test 5.2.1 Behavior of Specimen During Testing The second test comprising of both flexura l and torsional loading was conducted on January 6, 2010 at the Florida Department of Transportation Structures Research Center. There were concerns with bolt slippage due to both the flexural and torsional moment arm connections. Prior to testing, the sys tem was loaded with the crane only to remove some of the initial rotation due to bolt slippage (See Figure 58 ) During testing, t he test specimen was loaded at approximately 100 pounds force per second and the formation of cracks on the surface of the concrete was monitored. At approximately 10.8 kips bond between the concrete and the embedded pipe loosened, causing a change in stiffness At approxima tely 14.3 kips flexural and torsional cracks began to form on the concrete shaft (See Figure 59) At approximately 20.2 kips concrete breakout failure cracks began to form on the concrete shaft while the torsional cracks continued to widen (See Figure 510). At approximately 24.5 kips the concrete breakout failure cracks began to widen noticeably (See Figure 511). The foundation continued to be loaded until the specimen stopped taking on additional load The applied load peaked at approxim ately 26.3 kips At failure the foundation displayed the predicted breakout cone indicated by bulging concrete deep within the foundation. As intended, the rest of the test specimen did not fail before the predicted breakout failure occurred. Note that an applied load of 1 kip produces a flexural moment of 8 kipft and a torsional moment of 9 kipft.

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80 The formation of the initial cracks was noteworthy because it indicated a change in the concrete behavior from a concrete pedestal with anchor bolts and confi ning reinforcement Rather than the 45 degree torsional cracks forming at the surface of the concrete closest to the base plate, cracks parallel to the embedded pipe formed at the surface closest to the base plate. These parallel cracks extended several in ches down the foundation and then began to exhibit typical torsional 45 degree crack formation. This cracking behavior shows that the torsional load is being transferred from the steel to the concrete deeper in the foundation. This will be beneficial becau se the frequent construction mistake of placing the rebar cage too deep in the foundation often leaves the surface of the concrete under reinforced If the load will be transferred into the concrete deeper in the foundation, the problem of the under reinforced surface concrete will be partially negated. 5.2.2 Summary of LVDT Test Results Data was reduced to formulate an applied load versus rotation plot for both flexure and torsion. The plots show that the embedded pipe and plate configuration ceased taking on additional load after 26.3 kips after the concrete breakout failure from flexure resulting from the applied bending moment. The cylinder tests indicated that the compressive strength of concret e on the day of testing was 5180 psi. When the predictions with the 28 day concrete strength were made, the flexural concrete breakout was predicted to be 26.4 kips and the torsional concrete breakout was predicted to be 37.5 kips When the predictions with the 28 day concrete strength were made, the flexural side face blowout strength was predicted to be 40.9 kips and the torsional side face blowout strength was predicted to be 56.4 kips. The applied load versus torsional plate rotation plot also shows a change in slope when the specimen experienced a redistribution of load due to bolt slippage, bond changes formation of various cracks, and

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81 widening of cracks. See Figure 512 for the graph of applied load versus torsional plate rotation. See Figure 513 for the graph of the applied load versus flexural rotation. The graph of load versus torsional rotati on for the second test was created from data gathered from LVDTs place on the base plate of the embedded pipe. The graph showing the torsional rotation of the base plate for this test (Figure 512) shows significantly less rotation than the plate of the previous test ( Figure 56). This can be attributed to the fact that the LVDT wa s placed on the base plate attached to the moment arm on the previous test and the LVDT was placed on the base plate attached to the embedded pipe on this test. The moment arm base plate would feel more rotation because of the bolt slippage occurring at the connection. The graph of load versus flexural rotation was gathered from the LVDTs placed on the bottom of the base plate, front of shaft, and rear of shaft. The graph shows that the rotation between the face of the shaft and the base plate was significantly greater than the rotation between the face of the shaft and the rear of the shaft. This can be attributed to several things, including the steel pipe and base connection was less stiff than the concrete pedestal as well as the concrete block was adequately designed as a fixed support, which would have restrained the ro tation at the base and created a deflection that could be adequately described by an applied moment on a f ixed cantilever As stated earlier, the LVDTs gathered information from the base plate, the front of the concrete pedestal and the rear of the concrete pedestal. The base plates torsional rotation exceeded the rotations from the front of the concrete pe destal and the back of the concrete pedestal (See

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82 Figure 514 ). This shows that the steel pipe and base plate was less stiff than the concrete pedest al. The lack of considerable rotation in the rear of the concrete pedestal once again shows that the concrete block connected to the concrete pedestal was adequately designed as a fixed support. 5.2.3 Summary of Torsion and Flexure Test Overall, thi s test proved the embedded pipe and plates section was successful at transferring load from the superstructure to the substructure It was determined that the modified anchor bre akout equations for flexure also accurately predicted the behavior and strength of the failure The predicted failure load for the concrete breakout in flexure was 26.4 kips and the applied failure load was 26.3 kips, with the largest breakout occurring on the bottom of the test specimen, indicating a flexure failure. The test speci men had a breakout failure deep within the foundation at the approximate location of the flexural plate It was also determined that the alternative tested had approximately twice the strength of the calculated strength of an equivalent 12 anchor bolt syst em. For more details on the calculated strength of an equivalent anchor bolt system compared to the test apparatus strength, see the test apparatus calculations in Appendix B.

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83 Figure 51. Lines drawn on base plate to show bolt slippage Figure 52. Formation of torsional cracks

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84 Figure 53. Formation of concrete breakout failure cracks Figure 54. Concrete breakout f ailure cracks widen

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85 Figure 55. Specimen at failure Figure 56. Torsional moment and rotation plot for base plate of torsion test Predicted Maximum Failure Cracks Widen Failure Cracks Form Torsion Cracks Form Bolt Slippage Ends

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86 Figure 57. Torsional moment and rotation plot for torsion test Figure 58. Test specimen prior to testing Rear of Shaft Face of Shaft Outer Base Plate

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87 Figure 59. Torsional and flexural cracks forming Figure 510. Formation of concrete breakout failure cracks in second test

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88 Figure 511. Widening of concrete breakout failure cracks in second test Figure 512. Load and torsional rotation of base plate for torsion and flexure test Bond loosens Torsion and flexure cracks form Failure cracks widen Predicted failure Failure cracks form

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89 Figure 513. Load and flexural rotation for the second test Figure 514. Load and torsional rotation for test specimen for the second test Base plate to rear of shaft Predicted failure Failure cracks widen Base plate to face of shaft Face of shaft Bond loosens Bolt slippage ends Base plate Rear of shaft Face of shaft to rear of shaft

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90 CHAPTER 6 SUMMARY, CONCLUSIONS AND RECOMMENDATIONS The purpose of this research program was to determine a suitable alternative support structure for cantilever sign/signal structures and test the selected alternative to veri fy its viability. After a review of the problems with the current anchor bolt design and research into alternatives found in other fields, an embedded pipe and plate configuration was selected for testing. In order to quantify the strength of the embedded pipe and plate configuration, a review of current ACI 318 formulas relating to anchorage to concrete was conducted. The applicable equations regarding anchor breakout due to shear applied parallel to an edge as well as side face blowout due to an anchor in tension were modified to accommodate the differences in geometry and behavior of an anchor and the embedded pipe and plate system. Once the predicted strength in torsion and flexure was quantified, testing was conducted on two different specimens. The pur pose of the first experiment was to test primarily torsion, and the second experiment tested both torsion and flexure. The first test proved that the alternative selected was a viable alternative to transfer torsional load from the monopole to the foundati on. 6.1 Implications of Test Results 6.1.1 Torsion Test The implication of the torsion test is that the alternative selected is a viable alternative for transfer ring torsion from the monopole to the foundation. A comparison of the torsion test results and the calculated strength of an equivalent anchor bolt system in torsion show that the embedded pipe and plate configuration has double the strength of the equivalent anchor bolt system (See d esign calculations in Appendix B ) The predicted breakout pattern of a failure cone within the foundation at the approximate location of the torsion plates was exhibited during testing, signifying that the predicted behavior was likely correct. The modified concrete breakout

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91 equation s for torsion (See Equations 35 and 36) were proven accurate as the predicted failure load with these equations was less than 1% disparate from the tested failure load. The results imply that the embedded pipe and plate configuration in torsion alone would be an adequate alternative to the current anchor bolt system. The torsional strength of the alternative is greater than the anchor bolt system a nd can be accurately predicted using the modified concrete breakout equations for torsion. 6.1.2 Torsion and Flexure Test The implication of the torsion and flexure test is that the alternative selected, the embedded pipe with torsion and flexure plates, is a suitable alternative to the current design using anchor bolts. A comparison of the experimental test values and the calculated equivalent st rength of an anchor bolt setup show that the experimental test strength in flexure is approximately twice that of the equivalent anchor bolt system (See design calculations in Appendix B ) A large bulge of concrete on the bottom of the shaft signifies a co ncrete break out of the embedded flexure plate verifying the breakout was the failure mode. The modified concrete breakout equations for flexure (See Equations 3 8 and 39) were proven accurate as the predicted failure load with these equations was less th an 1% off from the tested failure load. These results imply that the tested system with the embedded pipe and torsion and fle xure plates is a viable alternative to the current anchor bolt system. The failure can be predicted accurately using both the torsi on and flexure plates and can easily be quantified using the modif ied concrete breakout equations 6.2 Recommendations for Future Testing 6.2.1 Introduction and Background Cantilever sign/signal structures typically have a single monopole supported by a c ast in place foundation. As was mentioned in Chapter 2, t he most common method of connecting the

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92 monopole to the foundation is through the use of anchor bolts attached to an annular plate welded to the monopole ( See Figure 61). Although this connection is the most widely used, many studies in the past few years have reported that fatigue of the annular plate and anchor bolt configuration is a significant concern. In the early 1990s it became evident that the Supports Specifications were not providing enough guidance on designing for vibration and fatigue. In response to the large problems with vibration and fatigue in cantilever signal/sign support structures, the National Cooperative Highway Research Program (NCHRP) initiated project 10 38 in 1993 (6) The information obtained from project 10 38 was published as NCHRP Report 412. The recommendations provided in NCHRP Report 412 were incorporated into the design provisions in the 2001 Supports Specifications NCHRP Report 412 found that galloping, vorte x shedding, natural wind gusts, and truckinduced wind gusts were the primary windloading mechanisms that were responsible for most vibration and fatigue related stresses on cantilever structures (7) Based on this information, importance factors were assigned for each of the four wind loading mechanisms on three fatigue categories. Report 412 describes, Structures classified as Category I would present a high hazard in the event of failure and should be designed to resist rar ely occurring wind loading and vibration phenomena (7) The fatigue design approach recommended by NCHRP Report 412, and adopted by the 2001 Supports Specifications was to design cantilever support structures to resist specif ied static wind loads, modified by the importance factors (3) The stresses obtained from the modified static wind loads would be designed to satisfy the requirements of their recommended detail categories for an infinite life fatigue design (3)

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93 Due to the lack of proper guidance on vibration and fatigue design in the Supports Specifications until the 2001 edition, many of the supports structures designed prior to the 2001 edition are now experienci ng fatigue problems, particularly on the welded annular base plate and anchor bolt connection (3) Despite the fact that NCHRP Report 412 finally gave guidance to designers on fatigue design for cantilever signal/sign support structures, the rate of fatigue cracking and failure has continued and may have even increased (6) Because of this, NCHRP Project 10 38(2) was initiated to further address fatigue resistant design of the cantilever support structures. The information obtained from Project 10 38(2) was published as NCHRP Report 469. NCHRP Report 469 partially attributes the continued fatigue problems with the increasing use of longer horizontal spans of the cantilever sign/signal structures (6) Past inspections have shown that the following typical and special problems on cantilever signal/sign structures are prevalent (16) : Cracked anchor bolts both above and within the concrete Loose nuts and missing connectors, both on anchor bolts and structural bolts Cracked and broken welds Split tubes Plugged drain holes, debris accumulation and corrosion Internal corrosion of tubular members Poor fit up of flanged connections with cracking and mi ssing bolts Structure overload due to installation of signs exceeding design square footage Some of the recommended revisions proposed in NCHRP Report 469 to the 2001 Supports Specifications fatigue design and partially incorporated into the 2006 Interim t o Standard Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals include the following (6; 17) : Clearly define criteria for categorizing the structure fatigue categories Galloping mi tigation devices (sign blanks or other proved mitigation devices) not be used to remove the galloping design load entirely, but would instead alter the fatigue category from Category I to Category II

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94 The equivalent static pressure range be changed from 1760 CD to 900CD for truck induced wind gusts A statement be included in the vortex shedding section, similar to that in the galloping section of the 2001 Supports Specifications, allowing for mitigation of vibration due to vortex shedding after a problem with vibration in double curvature has been observed Minor changes to the design some of the fatigue resistant details, with the inclusion of an additional fatigue resistant detail to be considered The problems identified with the fatigue of the steel annular base plate and the concrete breakout from the anchor bolts necessitates looking at alternatives to the current anchor bolt and base plate connection. The following are some options to explore regarding alternative connections that do not use the same ancho r bolt and annular base plate connection. 6.2.2 Tapered Embedded Steel Pipe and Plate Option with Bolted Slip Base Connection In this option, a tapered welded pipe and plate configuration will be embedded into the foundation with a portion of the pipe proj ecting from the foundation. The monopole will be placed over the projecting pipe, acting as a sleeve, and secured into place by several bolts that will extend through the diameter of the pole. See Figure 62 for a sketch of this connection. The primary benefit associated with this connection is that the annular plate and anchor bolts have been removed, thus eliminating the questionable connecting elements of the design. The design calculations for the bolted connection would be relatively eas y. The bolts would need to be designed for shear strength and the bearing strength of the bolt holes would also be a primary consideration. The embedded pipe and plate section has been tested to determine its torsional and flexural viability. Since the emb edded pipe and plate alternative has been proven effective at transferring load this connection would seem a likely candidate for consideration. However, one of the drawbacks to this design is the construction feasibility. A typical monopoles taper is 0.14 in/ft. In order to provide the shorter embedded tapered section, an additional pole would need to be ordered and cut to the appropriate length at the appropriate

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95 point on the pole. This process may prove tedious and time consuming. The connecting bolts bearing on the monopole may require an increase in pipe thickness for the monopole which could lead to additional expense. Additionally, this option would include corrosion as a potential problem since the entire connection is steel. Alignment of this connection may be difficult to accomplish during construction. One method possible to control the alignment would be to place the sleeve flush with the top of the concrete foundation. However, if a standoff was required, there might be difficulty leveling the monopole for placement. The bolt holes will ensure the final product will be level because they need to be aligned properly to ensure the bolts will fit through the holes. If a bolt is forced into place because of improper alignment it may incur additiona l stress. Design strength considerations for this connection include, but are not limited to, the following: Bolt shear strength Bolt bearing strength (on steel pipes) Fatigue (of bolts) Breakout strength (of embedded section on concrete foundation) Torsional strength Flexural strength This option provides a suitable alternative to the current annular plate and anchor bolt connection. The FDOT currently uses a detail similar to this in Index No. 11860, Single Column Ground Signs, in their Design Standards (18) See Figure 6 3 for a sketch of the FDOT detail. However, this detail has been specified for use with aluminum single column posts for ground signs and not for steel monopoles. 6.2.3 Embedded Steel Pipe and Plate Option with Grouted Slip Base Connection In this option, a standard welded pipe and plate configuration will be embedded into the foundation with a portion of the pipe pr ojecting from the foundation. The monopole will be

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96 placed over the projecting pipe, acting as a sleeve, and secured into place by several bolts that will extend through the diameter of the pole. The gap between the tapered monopole and the embedded pipes projection will be filled with high strength grout. See Figure 64 for a sketch of this connection. As with the tapered embedded steel pipe and plate option, the prim ary benefit associated with this connection is that the annular plate and anchor bolts have been removed. The design calculations for the bolted connection would be relatively easy. The bolts would need to be designed for shear strength and the bearing str ength of the bolt holes would also be a primary consideration. A benefit of this design over the tapered steel pipe design would be that the embedded steel pipe would be more easily obtained. One of the drawbacks to this design is the added complication of highstrength grout. Grout was found to be improperly placed in the current anchor bolt and base plate connection and has the potential to be improperly placed in this connection. Another potential drawback is that the connecting bolts bearing on the monopole may require an increase in pipe thickness for the monopole which could lead to additional expense. Additionally, this option would include corrosion as a potential problem since the entire connection is steel. Alignment of this option during construction may prove difficult because of the small tolerance for error on aligning the bolt holes. Allowing t he monopole to be placed directly on the concrete foundation will reduce some error. Design strength considerations for this connection include, but are not limited to, the following: Bolt shear strength Bolt bearing strength (on steel pipes) Fatigue (of bolts) Breakout strength (of embedded section on concrete foundation)

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97 Torsional strength Flexural strength This option provides a possible alternative to the current annular plate and anchor bolt connection. The FDOT currently uses a detail similar to this in Index No. 11860 in their Design Standards ( See Figure 6 3). However, this detail has only been used with aluminum single column posts for ground signs. 6.2.4 Embed ded Concrete Pipe with Bolts Option with Bolted Slip Base Connection In this option, a prestressed concrete pipe with bolts option, either tapered or not tapered, will be embedded into the foundation with a portion of the pipe extending beyond the foundati on. This option is very similar to the embedded steel pipe and plate option with slip base connection. One obvious difference would be that the embedded pipe would be concrete rather than steel. Another difference is that the embedded portion would have bolts acting in a manner similar to the plates. The bolts would connect plates to the concrete section. As explained later in this section, the embedded concrete pipe with bolts may be replaced with a geometric section without bolts if necessary. See Figure 65 for the overall setup of this connection as a concrete pipe with bolts. One immediate benefit associated with this configuration is that the annular plate and anc hor bolt connection has been removed. Another benefit over the embedded steel pipe and plate option is that this embedded concrete option removes corrosion of the embedded pipe as a potential problem. As with the previous option, the bolted connection bear ing on the monopole may require an increase in thickness for the monopole, leading to additional expense. A potentially difficult piece to construct would be the embedded concrete pipe with bolts. One option would be to order spun concrete poles from a ma nufacturer. The poles would include prestressed strands as well as spiral reinforcement and would be light and durable. The through

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98 bolt holes would be included by using a cast in place PVC pipe during fabrication. Another option would be to use a geometri c section without bolts instead of the round section with bolts. The geometric section would provide the required torsional resistance once embedded in the foundation that the bolts are providing in the round section. Design strength considerations for this connection include, but are not limited to, the following: Bolt shear strength Bolt bearing strength (on steel monopole) Bolt bearing strength (on embedded concrete section) Fatigue (of bolts) Breakout strength (of embedded section on concrete foundat ion) Torsional strength Flexural strength As with the previous option, the embedded steel pipe and plate option, this configuration may provide a suitable alternative to the current annular base plate and anchor bolt connection. As mentioned before, the FD OT currently uses a detail similar to this in Index No. 11860 in their Design Standards. Given that, the detail in the Design Standards has only been specified for use with aluminum single column posts for ground signs. 6.2.5 Cast in Place Solid Concrete Pedestal with Bolted Slip Base Connection In this option, a cast in place solid concrete pedestal would be poured projecting from the foundation with the tapered steel monopole placed over the pedestal projection and the two connected with bolts. Some longitudinal rebar would connect the solid concrete pedestal projection to the foundation. See Figure 66 for the setup of this connection. As with the previous option, one benefit to this connection would be that the annular base plate and anchor bolt connection would be eliminated. Another benefit to this connection is that the construction would be relatively easy because its all cast in place. One problem with this

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99 co nnection is that the connection may have less flexural strength because the rebar would be the only flexural reinforcement. And as with the other bolted slip connections, the bolt bearing may require an increase in monopole member thickness. Design streng th considerations for this connection include, but are not limited to, the following: Bolt shear strength Bolt bearing strength (on steel monopole) Bolt bearing strength (on cast in place solid concrete pedestal) Fatigue (of bolts) Torsional strength Flex ural strength 6.2.6 Embedded Concrete Pipe with Bolts Option with Grouted Splice to Concrete Monopole In this option, a prestressed concrete pipe with bolted plates would be embedded into a concrete foundation. The bolts and plates would resist torsion by bearing on the surrounding concrete foundation. The splice would be similar to that presented in FDOT Project BC35480 Final Report, Volume 2 (19) See Figure 6 7 for the setup of this connection. The splice connection would be a steel HSS pipe with welded rebar hoops placed in the hollow core of the prestressed spun concrete pipe and then pressure grouted into place. This option has several advantages over the current annular plate and anchor bolt connection. The primary advantage is that the connection does not use annular plates or anchor bolts and will eliminate the fatigue problems associated with the current connection option. Another advantage is that since the steel portion of the connection is grouted in the core of the spun concrete poles, the steel will not suffer as much corrosion unless one of the grout inlet holes is compromised.

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100 This opti on does have some disadvantages as well. The construction will be more tedious and time consuming than the current connection option. This connection can be more costly than the current connection option because of the increase in number of elements as wel l as the cost of each element. The inclusion of grout adds an additional complication for design and construction error. The viability of a concrete monopole for cantilever use is also questionable. The horizontal member that needs to be attached for sign/ signal purposes may be too large to attach to the concrete monopole. This connection may be more difficult to monitor and repair than a visible connection. Design strength considerations for this connection include, but are not limited to, the following: B reakout strength (of embedded section on concrete foundation) Grout strength Torsional strength Flexural strength Monopole to horizontal member connection 6.2.7 Embedded Steel Pipe and Hoops with Grouted Slip Base Connection This option entails using a steel pipe and hoops embedded into the foundation and stubbing out from the foundation. The steel pipe and hoops would then be covered by a concrete monopole and pressure grouted into place. See Figure 68 for this connection configuration. The primary benefit of this connection is that it removes the fatigue prone elements of the current anchor bolt and annular base plate connection. It offe rs good torsional and flexural resistance with the embedded pipe and hoop section. The pipe and hoop section may be expensive to fabricate. The pressure grouting has the potential to be a problem during construction as it has been a problem in the past. As mentioned earlier, the concrete monopole

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101 may not be viable to connect to the steel horizontal member. This connection may also be more difficult to monitor or repair than a visible connection. Design strength considerations for this connection include, but are not limited to, the following: Breakout strength (of embedded section on concrete foundation) Grout strength Torsional strength Flexural strength Monopole to horizontal member connection 6.2.8 Embedded Steel Pipe and Plates with Bolted Plate Connect ion In this option, an annular plate would be welded to both the monopole and the stub of the embedded steel pipe protruding from the foundation. The two annular plates would be bolted together, allowing for space between for leveling nuts to be used. The leveling nuts would make it easier to ensure the monopole was erected properly. See Figure 69 for the connection setup. One benefit with this connection is that it w ould be easy to construct and the materials would be easy to obtain. Since this option is very similar to the current base plate and anchor bolt option, it would not be difficult for designers to transition to this design. This option also provides the benefit that the embedded pipe would not need to be tapered and therefore could be more easily constructed by using a standard circular HSS section. However, one major drawback to this design is that it has the potential to have fatigue problems similar to t he current base plate and anchor bolt design. The welds, bolts, and plates could experience fatigue cracking after the cyclical wind stresses are imposed on the connection. Corrosion would also remain an issue with this connection. This connection does not necessarily fix the problem with fatigue associated with the current annular plate and anchor bolt design, but it does offer another alternative.

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102 Design considerations for this connection include, but are not limited to the following: Bolt shear strength Bolt bearing strength (on annular plates) Flexural strength (of annular plates and bolts) Weld strength Axial strength (of annular plates and bolts) Fatigue (of bolts, welds, and annular plates) As demonstrated by the increase in the number of design cons iderations, this option has more possibilities for failure. It does include welds, annular base plates, and bolts as the current base plate and anchor bolt option does. Therefore, this option does not eliminate the problems associated with the current base plate and anchor bolt design, other than removing anchor bolts as a potential failure and replacing it with a standard bolted connection. 6.2.9 Embedded Steel Pipe and Plates with Welded Sleeve Connection In this connection, a steel pipe and plate configuration would be embedded in the concrete foundation and connected to the steel monopole by a welded sleeve. The sleeve would consist of a high strength steel pipe section fillet welded to the monopole and e mbedded steel pipe and plates around the perimeter of the pipes. See Figure 6 10 for the connection detail. One benefit of this connection is that it would be relativ ely easy to construct and the materials would be easy to obtain. This connection does not use bolts and thus removes bolt fatigue as a problem. The annular plate is also removed, also eliminating fatigue problems with this component of a connection. Howev er, the fillet welds are susceptible to fatigue cracking similar to the current base plate and anchor bolt section. Corrosion would also remain an issue because the connection is comprised totally of steel. The welded sleeves pipe thickness would need to be large to handle the large flexural and torsional moments presented at the connection. This connection may make it difficult to align the monopole correctly during construction.

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103 Design considerations for this connection include, but are not limited to the following: Weld strength Fatigue (of welds) Flexural strength Torsional strength Breakout strength (of embedded section on concrete foundation) This option provides a solution to part of the fatigue problems associated with the annular plates, bolts, and welds. The welds will remain a fatigue problem. While this option may not solve all of the problems, it does provide a solution that may be relatively easy to construct. 6.2.10 Summary of Recommendations for Future Testing Future testing of alternative connections to resolve the fatigue and vibration problems exhibited in the current base plate and anchor bolt connection is highly recommended. The embedded pipe and plates configuration has been proven to be effective at transferring torsion and flexure and therefore a connection incorporating the embedded pipe and plates would be ideal. The option that may have the greatest potential that incorporates the embedded pipe and plates option is the grouted slip base connection. Th e benefits of this connection are that it includes the embedded pipe and plates, the design would be relatively simple, the anchor bolts are removed, and the fatigue prone welds that pr esent a problem are eliminated. 6.3 Summary The alternative selected, t he embedded pipe and plate configuration, has worked in transferring torsional and flexural load from the monopole to the foundation during experimental testing. The controlling failure behavior of the system is characterized by a concrete breakout in the shape of a cone in the vicinity of the embedded plates. The strength of the failure modes can be quantified by using modified ACI 318 equations. The embedded pipe and plate configuration also has potential to work in an alternative base connection that is recommended for future

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104 testing. The proper use of the findings in this testing program will allow for future prevention of the types of failures exhibited in the 2004 hurricane season.

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105 Figure 61. Typical sign/signal base connection Figure 62. Embedded steel pipe and plate option with slip base connection Bolt Tapered embedded steel pipe and plates Concrete foundation Tapered steel monopole sleeve Welded base plate Anchor bolt Monopole Concrete foundation

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106 Figure 63. FDOT Design Standards Index No. 11860(18) Figure 64. Embedded steel pipe and plate option with grouted slip base connection Tapered steel monopole Bolt Embedded steel pipe and plates Concrete foundation Grout Seal Aluminum column Sleeve bolt Aluminum sleeve Aluminum Concrete foundation Aluminum base plates High strength base bolt

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107 Figure 65. Embedded concrete pipe and plate option with slip base connection Figure 66. Cast in Place solid concrete pedestal with slip base connection Concrete foundation Longitudinal rebar Cast in Place solid concrete pedestal Tapered steel monopole sleeve Bolt Tapered steel monopole sleeve Bolt Embedded concrete pipe with bolts Concrete foundation Steel plate

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108 Figure 67. Embedded concrete pipe with bolts option with grouted splice to concrete monopole Figure 68. Embedded steel pipe and hoops with grouted slip base connection Concrete foundation Tapered concrete monopole sleeve Steel HSS pipe with welded rebar hoops and plates Grout Grout seal Embedded concrete pipe with bolts Concrete foundation Steel plate Tapered concrete monopole Steel HSS pipe with welded rebar hoops Grout l Grout

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109 Figure 69. Embedded steel pipe and plates with bolted plate connection Figure 610. Embedded steel pipe and plate with welded sleeve connection Embedded steel pipe and plates Concrete foundation Steel pipe sleeve Fillet weld Monopole Leveling nut Embedded steel pipe and plates Concrete foundation

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110 APPENDIX A T EST APPARATUS DRAWINGS Figure A 1. Dimensioned front elevation drawing of torsion test apparatus

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111 Figure A 2. Dimensioned plan view drawing of torsion test apparatus

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112 Figure A 3. Dimensioned side elevation drawing of torsion test apparatus

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113 Figure A 4. Dimensioned view of channel tie down for torsion test apparatus

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114 Figure A 5. Dimensioned drawings of embedded pipe and plate for torsion test

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115 Figure A 6. Dimensioned front elevation drawing of torsion and flexure test apparatus

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116 Figure A 7. Dimensioned plan drawing of torsion and flexure test apparatus

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117 Figure A 8. Dimensioned side view drawing of torsion and flexure test apparatus

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118 Figure A 9. Dimensioned drawing of channel tie down for torsion and flexure test

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119 Figure A 10 Dimensioned drawing of flexure extension pipe for torsion and flexure test

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120 Figure A 11 Dimensioned view of embedded pipe and plates for torsion and flexure test

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APPENDIX B DESIGN CALCULATIONS Torsion Design Calculations Input and Properties Shaft Diameter of the Shaft d s 26in Concrete Strength f c 5500psi Lenth of Shaft L s 36in Hoop Steel Hoop Steel Area A hoop .2in2 Hoop Steel Diameter d hoop .5in Spacing of Hoop Steel s hoop 2in Yield Strength of Hoop Steel f y_hoop 60ksi Centerline of Hoop Steel Diamter d h 22in Longitudinal Steel A long .2in2 Longitudinal Steel Area d long .5in Longitudinal Steel Diameter f y_long 60ksi Yield Strength of Longitudinal Steel n long 24 Number of Long Steel Bars Stiffener Plates Thickness of the plate t1in Width of the plate b1in Length of plate L7in Yield strength of the plate f y_plate 50ksi Embedded Pipe Thickness of the pipe t pipe .25in Diameter of the pipe d pipe 16in F y_pipe 42ksi F u_pipe 58ksi Moment Arm Moment_Arm9ft Input and Properties

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STIFFENER DESIGN Calculation of Capacity with Anchor Bolts Input Shaft Diameter of the Shaft d s 26in Concrete Strength f c 5.5ksi Equivalent Anchor Bolt Diameter of the bolt d o 1.5in Center-to-center diameter of bolts d b 20in Number of bolts No_Bolts_equiv12 Yield strength of bolts f y_bolt_equiv 105ksi Concrete Breakout Equivalent Torsional Strength Based on ACI 318 Appendix D Design requirements for shear loading cover d s d b 2 cover3in c a1 d b 2 23.25 d s 2 2d b 2 2 d b 2 3.25 c a1 2.46in A 360deg No_Bolts_equiv A30deg chord_group2 d s 2 sin A 2 chord_group6.73in A min_group 2asin 3.0c a1 d s A min_group 33.03deg Check_Group_Effect"Group Effect"AA min_group if "No Group Effect"otherwise Check_Group_Effect"Group Effect" A Vc No_Bolts_equivchord_group 1.5 c a1 A Vc 298.42in2 A Vco 4.5c a12 A Vco 27.31in2 l e 8d o l e 12in V b 13 l e d o .2 d o in f c psi c a1 in 1.5 lbf V b 6.92kip

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cV 1.4 ecV 1.0 edV 1.0 V cbg No_Bolts_equiv edV cV V b Check_Group_Effect"No Group Effect" = if A Vc A Vco ecV edV V b Check_Group_Effect"Group Effect" = if V cbg 75.62kip V cbg_parallel 2V cbg V cbg_parallel 151.23kip T n_breakout_ACI V cbg_parallel d b 2 T n_breakout_ACI 126.03ftkip Calculation of Capacity with Anchor Bolts Calculation of Capacity with Stiffener Plates Input Width of the stiffener plates b1in Thickness of the stiffener plates t1in Length of the stiffener plates L7in Length of the shaft L s 36in Diameter of upright/embedded pipe d pipe 16in Diameter of stiffeners d st d pipe Number of stiffeners No_Stiff4

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L breakout Avc Concrete Breakout Equivalent Torsional Strength Based on ACI 318 Appendix D Design requirements for shear loading cover d s d st 2 cover5in c a1 d st 2 23.25 d s 2 2d st 2 2 d st 2 3.25 c a1 3.73in A 360deg No_Stiff A90deg chord_group2 d s 2 sin A 2 chord_group18.38in A min_group 2asin 3.0c a1 d s A min_group 51.02deg Check_Group_Effect"Group Effect"AA min_group if "No Group Effect"otherwise Check_Group_Effect"No Group Effect"

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l breakout L21.5c a1 l breakout 18.2in A Vcp minl breakout L s 3 c a1 A Vcp 203.77in2 A Vco 4.5c a12 A Vco 62.69in2 l e L l e 7in V b 13 l e b .2 b in f c psi c a1 in 1.5 lbf V b 10.26kip V cbp A Vcp A Vco ecV edV cV No_Stiff V b V cbp 186.75kip V cbp_parallel 2V cbp V cbp_parallel 373.5kip T n_breakout_plate V cbp_parallel d st 2 T n_breakout_plate 249ftkip Calculation of Capacity with Stiffener Plates Calculation of Capacity with Side-Face Blowout Input Width of the stiffener plates b1in Thickness of the stiffener plates t1in Length of the stiffener plates L7in Length of the shaft L s 36in Diameter of upright/embedded pipe d pipe 16in Diameter of stiffeners d st 16in Number of stiffeners No_Stiff4 Concrete Side-Face Blowout Equivalent Torsional Strength Based on ACI 318 Appendix D c a1 d st 2 23.25 d s 2 2d st 2 2 d st 2 3.25 c a1 3.73in A brg Lb 7in2

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N sb 200c a1 A brg f c psi psi N sb 146.48kip T n_blowout No_StiffN sb d st 2 T n_blowout 390.6ftkip Calculation of Capacity with Side-Face Blowout Capacity Check Check_Capacity"Sufficient Strength"T n_breakout_plate T n_breakout_ACI if "Insufficient Strength"otherwise Check_Capacity"Sufficient Strength" T n_breakout_plate T n_breakout_ACI 1.98 Capacity Check Welding for Stiffener Plates Weld Design T n_breakout_plate 249ftkip V weld T n_breakout_plate 4.5d pipe V weld 93.37kip t1in t pipe 0.25in Weld_Size 3 8 in AISC Spec. J2 Table J2.4 F electrode 70ksi F W .6F electrode 42ksi AISC Spec. J2 Table J2.5 Throat.707Weld_Size 0.27in weld .75 R n_weld weld ThroatF W R n_weld 8.35 kip in R n_yield .6F y_pipe t 2 R n_yield 12.6 kip in

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R n_rupture weld .6 F u_pipe t 2 R n_rupture 13.05 kip in R n minR n_weld R n_yield R n_rupture R n 8.35 kip in Required_Length_Each_Side V weld 2R n Required_Length_Each_Side5.59in ceil Required_Length_Each_Side in in 6in Welding for Stiffener Plates T n_breakout_ACI 126.03ftkip T n_breakout_plate 249ftkip T n_blowout 390.6ftkip FLEXURAL CAPACITY Flexural Capacity of Shaft Check Flexural Capacity of Shaft Input Radius of Shaft Rd s 2 13in Area of shaft A s d s 2 2 Longitudinal Reinforcement n long 24 Number of Longitudinal Bars f y_long 60ksi Yield Strength of Longitudinal Reinforcement A long 0.2in2 Longitudinal Steel Area n long_yield 17 Number of Bars Yielded Calculations Using ACI Stress Block at the Point Below the Embedded Pipe 1 f c.85f c 4000psi if .65f c 8000psi if .85.05 f c 4000psi 1000psi 4000psif c 8000psi if 1 f c0.78 ACI 10.2.7.3 A comp n long_yield A long f y_long .85f c A comp 43.64in2

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A compcircle h ()R2acos Rh () R Rh ()2R h h2 A comp arootA compcircle h ()h 0in R a3.55in c = 4.59 in. y = 3.06 in. 17 Bars Below Yield Line c a 1 f c c4.59in y.002 c .003 y3.06in d bar 8.0000 10.4118 13.0000 15.5882 18.0000 20.0711 21.6603 22.6593 in d bars0 7 id bariA long 2 23.5inA long n long_yield A long d bars 16.6in M n_shaft n long_yield A long f y_long d bars a 2 M n_shaft 252.07ftkip Flexural Capacity of Shaft

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Flexural Capacity of Pipe Embedded Pipe Cross sectional area of pipe A pipe 22.7in2 Inside diameter of pipe d pipe 16in Pipe wall thickness t pipe 0.25in Yield Strength of Pipe F y_pipe 42ksi Diameter to thickness ratio D_t d pipe t pipe 64 Length of the pipe L pipe 3ft Modulus of elasticity E29000ksi Determine Shear Strength of Round HSS L v L pipe 2 F cr_1 max 1.6E () L v d pipe D_t ()5 4 .78E () D_t ()3 2 F cr_1 241.67ksi F cr minF cr_1 .6F y_pipe F cr 25.2ksi V n_pipe F cr A pipe 2 V n_pipe 286.02kip Determine Flexural Capacity of Round HSS Check_ApplicableifD_t .45E F y_pipe "Applicable" "N/A" Check_Applicable"Applicable" p .07 E F y_pipe r .31 E F y_pipe Check_Compact"Compact"D_t p if "Noncompact" p D_t r if "Slender"D_t r if Check_Compact"Noncompact"

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Z112in3 M p F y_pipe Z M n_pipe M p M n_pipe 392ftkip Flexural Capacity of Pipe M n_pipe 392ftkip M n_shaft 252.07ftkip FAILURE EQUATIONS Torsion Threshold Torsion A cp d s 2 2 530.93in2 p cp d s 81.68in T threshold f c psi psi A cp2 p cp T threshold 21.33ftkip ACI 11.6.1a Cracking Torsion T cr 4 f c psi psi A cp2p cp T cr 85.31ftkip ACI R11.6.1 Nominal Torsional Strength A o d h 2 2 380.13in2 A t d hoop 2 2 0.2in2 45deg 0.79rad T torsion 2A o A t f y_hoop s hoop cot () T torsion 373.19ftkip ACI 318-05 11.6.3.6 (11-21)

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T n_shaft T torsion T n_shaft 373.19ftkip ACI 318-05 11.6.3.5 (11-20) Torsion T n_breakout_plate 249ftkip T n_blowout 390.6ftkip T n_shaft 373.19ftkip DEVELOPMENT LENGTHS OF FLEXURAL REINF. Development and Splice Lengths Input Longitudinal Steel A long 0.2in2 Longitudinal Steel Area d long 0.5in Longitudinal Steel Diameter f y_long 60ksi Yield Strength of Longitudinal Steel Hoop Steel Hoop Steel Area A hoop 0.2in2 Hoop Steel Diameter d hoop 0.5in Spacing of Hoop Steel s hoop 2in Yield Strength of Hoop Steel f y_hoop 60ksi Centerline of Hoop Steel Diameter d h 22in Development Length of Longitudinal Reinforcement b t 1.3 ACI 318-05 12.5.2 b e 1.0 b s 1.0 1.0 Cb_Ktr2.5in ACI 318-05 12.2.3 l dh_long 3 40 f y_long f c psi psi b t b e b s Cb_Ktr d long d long l dh_long 7.89in ACI 318-05 12.2.3

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l d_long l dh_long 7.89in l d_long 7.89in ACI 318-05 12.2.5 l d_l ceil l d_long in in l d_l 8in Splice of Hoop Steel b t 1.0 ACI 318-05 12.5.2 b e 1.0 b s 1.0 1.0 Cb_Ktr2.5in ACI 318-05 12.2.3 l splice f y_hoop b t b e 25 f c psi psi d hoop l splice 16.18in ACI 318-05 12.2.3 Development and Splice Lengths Length of Shaft Required Length of Stiffeners L7in Length of Breakout l breakout 18.2in Length of Shaft L s 36in Development Length of Longitudinal Reinforcement l d_l 8in Required Cover c_cover2.5in Required Length of Shaft Based on Breakout and Development Length l shaft l breakout c_cover l d_l l shaft 28.7in Check_Shaft_LengthifL s l shaft "Sufficient" "Not Sufficient" Check_Shaft_Length"Sufficient" Length of Shaft Required

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SUPERSTRUCTURE Superstructure Assembly Strength Pipes Superstructure Test Assembly Pipe Pipe Properties HSS 16x.500 Design Wall Thickness t pipe .465in Cross Sectional Area of Pipe A pipe 22.7in2 Diameter to Wall Thickness Ratio D_t34.4 Moment of Inertia I pipe 685in4 Elastic Section Modulus S pipe 85.7in3 Radius of Gyration r pipe 5.49in Plastic Section Modulus Z pipe 112in3 Diameter of the Pipe D pipe 16in Torsional Constant J pipe 1370in4 HSS Torsional Constant C pipe 171in3 Yield Strength F y_pipe 42ksi Ultimate Strength F u_pipe 58ksi Modulus of Elasticity E29000ksi Length of Short Superstructure Pipe L s_pipe 17in Length of Long Superstructure Pipe L l_pipe 9ft Short PipeDesign Flexural Strength M n_s_pipe F y_pipe Z pipe D_t.45 E F y_pipe if "Equation Invalid"otherwise M n_s_pipe 392ftkip AISC Spec. F2.1 Design Shear Strength F cr 1.60E () L s_pipe D pipe D_t ()1.25 1.60E () L s_pipe D pipe D_t ()1.25 .78E () D_t ()1.5 if .78E () D_t ()1.5 otherwise

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F cr_shear minF cr .6F y_pipe F cr_shear 25.2ksi V n_s_pipe F cr_shear A pipe 2 V n_s_pipe 286.02kip AISC Spec. G6 Design Torsional Strength F cr 1.23E () L s_pipe D pipe D_t ()1.25 1.23E () L s_pipe D pipe D_t ()1.25 .60E () D_t ()1.5 if .60E () D_t ()1.5 otherwise F cr_torsion minF cr .6F y_pipe F cr_torsion 25.2ksi T n_s_pipe F cr_torsion C pipe T n_s_pipe 359.1ftkip AISC Spec. H3.1 Design Axial Strength r .31 E F y_pipe r 214.05 p .07 E F y_pipe "Compact"D_t p if "Noncompact" p D_t r if "Slender"D_t r if "Compact" AISC Spec. B4 k s_pipe .5 F e_short 2E k s_pipe L s_pipe r pipe 2 F e_short 119400.07ksi AISC Equation E3-4 F cr_short .658F y_pipe F e_short F y_pipe F e_short .44F y_pipe if .877F e_short F e_short .44F y_pipe if P n_s_pipe F cr_short A pipe P n_s_pipe 953.26kip AISC Equation E3-1

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Summary for Short Pipe Flexural Strength M n_s_pipe 392ftkip Shear Strength V n_s_pipe 286.02kip Torsional Strength T n_s_pipe 359.1ftkip Axial Strength P n_s_pipe 953.26kip Long PipeDesign Flexural Strength M n_l_pipe F y_pipe Z pipe D_t.45 E F y_pipe if "Equation Invalid"otherwise M n_l_pipe 392ftkip AISC Spec. F2.1 Design Shear Strength F cr 1.60E () L l_pipe D pipe D_t ()1.25 1.60E () L l_pipe D pipe D_t ()1.25 .78E () D_t ()1.5 if .78E () D_t ()1.5 otherwise F cr_shear minF cr .6F y_pipe F cr_shear 25.2ksi V n_l_pipe F cr_shear A pipe 2 V n_l_pipe 286.02kip AISC Spec. G6 Design Torsional Strength F cr 1.23E () L l_pipe D pipe D_t ()1.25 1.23E () L l_pipe D pipe D_t ()1.25 .60E () D_t ()1.5 if .60E () D_t ()1.5 otherwise F cr_torsion minF cr .6F y_pipe F cr_torsion 25.2ksi T n_l_pipe F cr_torsion C pipe T n_l_pipe 359.1ftkip AISC Spec. H3.1

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Design Axial Strength r .31 E F y_pipe r 214.05 p .07 E F y_pipe "Compact"D_t p if "Noncompact" p D_t r if "Slender"D_t r if "Compact" AISC Spec. B4 k long_pipe 2.0 F e_long 2E k long_pipe L l_pipe r pipe 2 F e_long 184.9ksi AISC Equation E3-4 F cr_long .658F y_pipe F e_long F y_pipe F e_long .44F y_pipe if .877F e_long F e_long .44F y_pipe if P n_l_pipe F cr_long A pipe P n_l_pipe 866.93kip AISC Equation E3-1 Summary for Long Pipe Flexural Strength M n_l_pipe 392ftkip Shear Strength V n_l_pipe 286.02kip Torsional Strength T n_l_pipe 359.1ftkip Axial Strength P n_l_pipe 866.93kip Superstructure Assembly Strength Pipes

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Superstructure Assembly Strength Connecting Plates Superstructure Test HSS Connection Plate Plate Properties PL1/2" x 32" x 24" Plate thickness t p .5in Plate length h p 32in Plate width b p 24in Yield strength F y_plate 50ksi Ultimate strength F u_plate 62ksi Design Tensile Strength P n_yield F y_plate t p b p P n_yield 600kip AISC Spec. D2a U1.0 AISC Table D3.1 A n t p b p AISC D3.2 A e UA n A e 12in2 AISC D3.3 t_rupt .75 P n_rupture t_rupt A e F u_plate P n_rupture 558kip P n_plate minP n_yield P n_rupture P n_plate 558kip AISC D2b Design Flexural Strength A g t p b p A g 12in2 L b 16in I p b p t p3 3 c t p 2 S p I p c S p 0.02gal M y S p F y_plate M y 16.67ftkip Z p t p b p 2 t p 2 Z p 0.01gal M p F y_plate Z p M p 6.25ftkip

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p M p_yield 1.6M y 1.6M y M p if M p otherwise M p_yield 6.25ftkip LTB_Equation_Check"Equation F11-2" .08E () F y_plate L b b p t p2 1.9E () F y_plate if "Equation F11-3" L b b p t p2 1.9E () F y_plate if LTB_Equation_Check"Equation F11-3" C b 1.0 AISC F1 F cr 1.9E C b L b b p t p2 F cr 35.87ksi M n_ltb F cr S p LTB_Equation_Check"Equation F11-3" = if C b 1.52.274L b b p t p2 F y_plate E kip in otherwise M n_ltb 11.96ftkip M n_plate M n_ltb M n_ltb M p_yield if M p_yield otherwise M n_plate 6.25ftkip Design Torsional Strength M t_plate F y_plate .6 M t_plate 30ksi Summary for Plate Connector Tensile Strength P n_plate 558kip Flexural Strength M n_plate 6.25ftkip M t_plate 30ksi Torsional Strength Weld Design V weld T n_blowout Moment_Arm V weld 43.4kip t p 0.5in t pipe 0.47in Weld_Size 3 16 in AISC Spec. J2 Table J2.4

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F electrode 70ksi F W .6F electrode AISC Spec. J2 Table J2.5 weld .75 Throat.707Weld_Size R n_weld weld Throat F W R n_weld 4.18 kip in R n_yield .6F y_pipe t p R n_yield 12.6 kip in R n_rupture .45F u_pipe t p R n_rupture 13.05 kip in R n min R n_weld R n_yield R n_rupture R n 4.18 kip in Required_Length_Each_Side V weld R n Required_Length_Each_Side10.39in ceil Required_Length_Each_Side in in 11in Superstructure Assembly Strength Connecting Plates Base Connection Superstructure Test Base Connection Plate Plate Properties Annular Plate Plate diameter B p 24in Yield strength f y_ann 50ksi Ultimate strength f u_ann 75ksi Thickness of plate t plate 1.00in Bolt Properties D1" ASTM A325 Center to Center Radius of Bolts r b 12in Number of Bolts No_Bolts12 Field Strength of Bolts f y_bolt_field 55ksi Ultimate Strength of Bolts f u_bolt 105ksi Radius of the pipe r p D pipe 2 8in Diameter of the bolt d bolt 1.5in

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Bolt Bearing Strength L c B p d b .5d bolt 2 1.62in shear .75 R n 1.2F u_plate L c t plate R n 120.9kip Rn_parallel2 R n Rn_parallel241.8kip T n_bolt_bearing No_BoltsRn_parallel d b 2 T n_bolt_bearing 2418ftkip Check_Bolt_Bearing"Sufficient Strength"T n_bolt_bearing T n_blowout if "Insufficient Strength"otherwise Check_Bolt_Bearing"Sufficient Strength" Check Bolt Spacing s req 2.67d bolt 4in s actual d b 12 5.24in Check_Bolt_Spacing"Sufficient"s actual s req if "Insufficient"otherwise Check_Bolt_Spacing"Sufficient" Check Bolt Shear A b .5d bolt 2 1.77in2 F nv .4120 ksi48ksi V n shear A b F nv V n 63.62kip V n_parallel V n 2 V n_parallel 127.23kip T bolt_shear No_BoltsV n_parallel d b 2 T bolt_shear 1272.35ftkip Check_Bolt_Shear"Sufficient Strength"T bolt_shear T n_blowout if "Insufficient Strength"otherwise Check_Bolt_Shear"Sufficient Strength"

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Weld Design V weld 43.4kip Weld Connecting Annular Plate to Pipe t pipe 0.47in Weld_Size 3 8 in AISC Spec. J2 Table J2.4 F electrode 70ksi F W .6F electrode AISC Spec. J2 Table J2.5 Throat.707Weld_Size R n_weld ThroatF W R n_weld 11.14 kip in R n_yield .6F y_pipe t pipe R n_yield 11.72 kip in R n_rupture .45F u_pipe t pipe R n_rupture 12.14 kip in R n minR n_weld R n_yield R n_rupture R n 11.14 kip in R weld R n d pipe R weld 559.72kip T weld R weld d pipe 2 T weld 373.15ftkip Base Connection

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CONCRETE BLOCK Concrete Block Design Strut-and-Tie Model Based on ACI 318 Appendix A Mmax Tension Tie Compression Struts R 6'-0" 4" 4" 9'-6" 10'-0" 6" 5'-0" 6'-0" M max T n_blowout 4.5ft 9ft M max 195.3ftkip d6ft8in d80in R M max d R29.3kip Node A atan5 ft d 36.87deg C R sin () C48.83kip TCcos () T39.06kip

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Check Reinforcement No_Bars_Block_Reinf3 Block_Reinf_Bar_No8 f y_block_reinf 60ksi A block_reinf No_Bars_Block_Reinf Block_Reinf_Bar_No8 2 2 in2 A block_reinf 2.36in2 Check_Block_Reinf_A"Sufficient"A block_reinf f y_block_reinf T if "Not Sufficient"otherwise Check_Block_Reinf_A"Sufficient" Concrete Block Design Strut-and-Tie Model Concrete Block Design Beam Theory R 4" 3'-0" 4'-9" 5'-0" Vblock M V block R V block 29.3kip M block R3ft4in () M block 97.65ftkip From strut-and-tie model... A block_reinf 2.36in2 f y_block_reinf 60ksi

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Check Shear Check_Shear_B"Sufficient"A block_reinf f y_block_reinf V block if "Insufficient"otherwise Check_Shear_B"Sufficient" Check Flexure b block 30in h block 6ft d block 5.5ft T given A block_reinf f y_block_reinf T given 141.37kip Ca ().85f c b block a Pa ()Ca()T given arootPa ()a 0in h block a1.01in 1 f c0.78 c a 1 f c c1.3in M n_block T given d block a 2 M n_block 771.61ftkip Check_Flexure_B"Sufficient"M n_block M block if "Insufficient"otherwise Check_Flexure_B"Sufficient" Required Hook Length for a #8 bar Hook_No_812 Block_Reinf_Bar_No 8 in Hook_No_812in ACI 318-05 Fig. 12.5 Concrete Block Design Beam Theory Summary of Concrete Block Reinforcement Block_Reinf_Bar_No8 No_Bars_Block_Reinf3 Check_Block_Reinf_A"Sufficient" Check_Shear_B"Sufficient" Check_Flexure_B"Sufficient" Summary of Concrete Block Reinforcement

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Tie-Down Design Block Properties Width of the block b block 30in Height of the block h block 6ft Length of the block l block 10ft Diameter of the shaft d s 26in Length of the shaft l shaft 36in Weight of concrete w c 150pcf Maximum shear applied V max T n_blowout Moment_Arm Channel Assembly 2 C12x30 Channels with 1.75" between Moment of inertia about strong axis I x 162in4 S x 27.0in3 Radius of gyration about strong axis r x 4.29in Z x 33.8in3 Cross sectional area A channel 8.81in2 Moment of inertia about weak axis I y 5.12in4 Radius of gyration about weak axis r y .762in x_bar.674in Yield strength F y_channel 50ksi Modulus of elasticity E29000ksi Web thickness t w .510in Flange width b f 3.17in Flange thickness t f .501in Depth h12in

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Vmax R1 W1 W2 1'-3" 2'-6" 3'-0" 1'-6" 7'-4" 6'-0" 8" 5'-4" 8" Calculate self-weight of block W 1 h block b block l block w c W 1 22.5kip W 2 l shaft d s 2 2 w c W 2 1.66kip Calculate the Load that the Tie-down must resist in each direction R 1 W 2 l shaft 2 b block W 1 b block 2 V max l shaft 17.5in b block b block R 1 106.89kip

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5'-0" 5'-0" Centerline of Support 4" 4" W1 + W2 Vmax 3'-0" 3'-0" R2 R 2 V max L l_pipe 3ft 4in W 1 W 2 3ft4in () 6.67ft R 2 68.18kip Total Load that the Tie-down must support R R 1 2 R 2 R121.62kip Check that the load is less than the capacity of the floor Floor_Capacity200kip Check_Floor_Capacity"Sufficient"Floor_CapacityR if "Insufficient"otherwise Check_Floor_Capacity"Sufficient" Check Bearing Strength of Concrete Conservatively assume that the load bears on 1 in. of concrete across the length of the block... A bearing l block 1 in A bearing 120in2 bearing .65

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Bearing_Strength bearing .85 f c A bearing Bearing_Strength364.65kip Check_Bearing_Capacity"Sufficient"Bearing_Strength2R if "Insufficient"otherwise Check_Bearing_Capacity"Sufficient" 7'-4" 8" 5'-4" 8" Rr Rl Papp Required Capacity of the Channel Assembly P app R P app 121.62kip R L P app 2 ft 6ft R L 40.54kip R R P app R L R R 81.08kip a4ft b2ft M max_tiedown P app a b ab M max_tiedown 162.16ftkip Flexural Capacity of Each Channel M n_tiedown F y_channel 2Z x M n_tiedown 281.67ftkip AISC Spec. F2.1 (F2-1)

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Check_Flexure_Channels"Sufficient"M n_tiedown M max_tiedown if "Insufficient"otherwise Check_Flexure_Channels"Sufficient" Buckling Check of Each Channel Treated as 2 separate channels f b f 2t f f 3.16 w h t w w 23.53 pf .38 E F y_channel pf 9.15 AISC Spec. B4 pw 3.76 E F y_channel pw 90.55 AISC Spec. B4 Check_Flange_Compact"Compact" pf f if "Not Compact"otherwise Check_Flange_Compact"Compact" AISC Spec. B4 Check_Web_Compact"Compact" pw w if "Not Compact"otherwise Check_Web_Compact"Compact" AISC Spec. B4 Bracing Check of Each Channel L b b L b 2ft L p 1.76r y E F y_channel L p 2.69ft AISC Spec. F2.2 (F2-5) Bracing_Check"Braced"L p L b if "Unbraced"otherwise Bracing_Check"Braced"

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Checking Channel Assembly I y_unit 2I y A channel x_bar 1.75in 2 2 I y_unit 52.52in4 r y_unit I y_unit A channel r y_unit 2.44in L p_unit 1.76r y_unit E F y_channel L p_unit 103.49in b f_unit 2b f 1.75in b f_unit 8.09in t w_unit 2t w 1.75in t w_unit 2.77in f_unit b f_unit 2t f f_unit 8.07 w_unit h t w_unit w_unit 4.33 Check_Flange_Compact_Unit"Compact" pf f_unit if "Not Compact"otherwise Check_Flange_Compact_Unit"Compact" Check_Web_Compact_Unit"Compact" pw w_unit if "Not Compact"otherwise Check_Web_Compact_Unit"Compact" Bracing_Check_Unit"Braced"L p_unit L b if "Unbraced"otherwise Bracing_Check_Unit"Braced" Weld Design V weld maxR L R R V weld 81.08kip t pl .5in b pl 5in Qt pl b pl t pl 2 h 2 Q15.62in3 I weld 2I x 2t pl b pl t pl 2 h 2 2 1 12 b pl t pl3 I weld 519.42in4

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Required_Load_per_Foot V weld Q I weld Required_Load_per_Foot29.27 kip ft Weld_Size 3 8 in F electrode 70ksi F W .6F electrode 42ksi AISC Spec. J2 Table J2.5 weld .75 Throat.707Weld_Size Required_Length_Per_Foot Required_Load_per_Foot weld F W Throat Required_Length_Per_Foot3.5 in ft Specify 4" per foot of Weld AISC Spec. J2.4 (J2-3) Tie-Down Design T max T n_blowout 390.6ftkip V max 43.4kip M max 195.3ftkip

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Torsion and Flexure Design Calculations Input and Properties Shaft Diameter of the Shaft d s 30in Concrete Strength f c 5178psi Lenth of Shaft L s 36in Hoop Steel Hoop Steel Area A hoop .11in2 Hoop Steel Diameter d hoop .375in Spacing of Hoop Steel s hoop 2.5in Yield Strength of Hoop Steel f y_hoop 60ksi Centerline of Hoop Steel Diamter d h 27in Longitudinal Steel A long .2in2 Longitudinal Steel Area d long .5in Longitudinal Steel Diameter f y_long 60ksi Yield Strength of Longitudinal Steel n long 24 Number of Long Steel Bars Torsional Stiffener Plates Thickness of the plate t1in Width of the plate b1in Length of plate L7in Yield strength of the plate f y_plate 50ksi Flexural Stiffener Plates Width of the stiffener plates b flex_plate 1in Thickness of the stiffener plates t flex_plate 1in Length of the stiffener plates L flex_plate 3in Embedded Pipe Thickness of the pipe t pipe .465in Diameter of the pipe d pipe 16in F y_pipe 42ksi F u_pipe 58ksi Moment Arm Tors_Moment_Arm9ft Flex_Moment_Arm8ft Input and Properties

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STIFFENER DESIGN Calculation of Capacity with Anchor Bolts Input Shaft Diameter of the Shaft d s 30in Concrete Strength f c 5.18ksi Equivalent Anchor Bolt Diameter of the bolt d o 1.5in Center-to-center diameter of bolts d b 20in Number of bolts No_Bolts_equiv12 Yield strength of bolts f y_bolt_equiv 105ksi Concrete Breakout Equivalent Torsional Strength Based on ACI 318 Appendix D Design requirements for shear loading cover d s d b 2 cover5in c a1 d b 2 23.25 d s 2 2d b 2 2 d b 2 3.25 c a1 3.85in A 360deg No_Bolts_equiv A30deg chord_group2 d s 2 sin A 2 chord_group7.76in A min_group 2asin 3.0c a1 d s A min_group 45.24deg Check_Group_Effect"Group Effect"AA min_group if "No Group Effect"otherwise Check_Group_Effect"Group Effect" A Vc No_Bolts_equivchord_group 1.5 c a1 A Vc 537.55in2 A Vco 4.5c a12 A Vco 66.57in2 l e 8d o l e 12in

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V b 13 l e d o .2 d o in f c psi c a1 in 1.5 lbf V b 13.1kip cV 1.4 ecV 1.0 edV 1.0 V cbg No_Bolts_equiv edV cV V b Check_Group_Effect"No Group Effect" = if A Vc A Vco ecV edV V b Check_Group_Effect"Group Effect" = if V cbg 105.77kip V cbg_parallel 2V cbg V cbg_parallel 211.55kip T n_breakout_ACI V cbg_parallel d b 2 T n_breakout_ACI 176.29ftkip Calculation of Capacity with Anchor Bolts Torsional Capacity Using Breakout Capacity Input Width of the stiffener plates b1in Thickness of the stiffener plates t1in Length of the stiffener plates L7in Length of the shaft L s 36in Diameter of upright/embedded pipe d pipe 16in Diameter of stiffeners d st d pipe Number of stiffeners No_Stiff4

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L breakout Avc Concrete Breakout Equivalent Torsional Strength Based on ACI 318 Appendix D Design requirements for shear loading cover d s d st 2 cover7in c a1 d st 2 23.25 d s 2 2d st 2 2 d st 2 3.25 c a1 4.99in A 360deg No_Stiff A90deg chord_group2 d s 2 sin A 2 chord_group21.21in A min_group 2asin 3.0c a1 d s A min_group 59.93deg Check_Group_Effect"Group Effect"AA min_group if "No Group Effect"otherwise Check_Group_Effect"No Group Effect" l breakout L21.5c a1 l breakout 21.98in A Vc minl breakout L s 3 c a1 A Vc 329.43in2 A Vco 4.5c a12 A Vco 112.27in2 l e L l e 7in

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V b 13 l e b .2 b in f c psi c a1 in 1.5 lbf V b 15.41kip V cbg A Vc A Vco ecV edV cV V b V cbg 63.31kip V cbg_parallel 2V cbg V cbg_parallel 126.62kip V c V cbg_parallel No_Stiff V c 506.46kip T n_breakout_plate V c d st 2 T n_breakout_plate 337.64ftkip Torsional Capacity Using Breakout Capacity Torsional Capacity Using Side-Face Blowout Capacity Input Width of the stiffener plates b1in Thickness of the stiffener plates t1in Length of the stiffener plates L7in Length of the shaft L s 36in Diameter of upright/embedded pipe d pipe 16in Diameter of stiffeners d st d pipe Number of stiffeners No_Stiff4 Concrete Breakout Equivalent Torsional Strength Based on ACI 318 Appendix D c a1 d st 2 23.25 d s 2 2d st 2 2 d st 2 3.25 c a1 4.99in A brg Lb 7in2 N sb 200c a1 A brg f c.5 psi.5 N sb 190.19kip T n_blowout No_StiffN sb d st 2 T n_blowout 507.17ftkip Torsional Capacity Using Side-Face Blowout Capacity

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Capacity Check Check_Capacity"Sufficient Strength"T n_breakout_plate T n_breakout_ACI if "Insufficient Strength"otherwise Check_Capacity"Sufficient Strength" T n_breakout_plate T n_breakout_ACI 1.92 Capacity Check Welding for Stiffener Plates Weld Design V weld T n_blowout 4.5d s V weld 101.43kip t1in t pipe 0.47in Weld_Size 3 8 in AISC Spec. J2 Table J2.4 F electrode 70ksi F W .6F electrode AISC Spec. J2 Table J2.5 Throat.707Weld_Size R n_weld ThroatF W R n_weld 11.14 kip in R n_yield .6F y_pipe t 2 R n_yield 12.6 kip in R n_rupture .45F u_pipe t 2 R n_rupture 13.05 kip in R n minR n_weld R n_yield R n_rupture R n 11.14 kip in Required_Length_Each_Side V weld 2R n Required_Length_Each_Side4.55in ceil Required_Length_Each_Side in in 5in Welding for Stiffener Plates

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T n_breakout_ACI 176.29ftkip T n_breakout_plate 337.64ftkip T n_blowout 507.17ftkip FLEXURAL CAPACITY Equivalent Bolt Flexural Capacity Input Shaft Diameter of the Shaft d s 30in Concrete Strength f c 5.18ksi Equivalent Anchor Bolt Diameter of the bolt d o 1.5in Center-to-center diameter of bolts d b 20in Number of bolts No_Bolts_equiv12 Yield strength of bolts f u_bolt_equiv 125ksi Calculate flexural capacity... A b d o 2 2 A b 1.77in2 M n_bolt A b f u_bolt_equiv No_Bolts_equiv d o 4 M n_bolt 82.83ftkip Equivalent Bolt Flexural Capacity Flexural Capacity of Shaft Check Flexural Capacity of Shaft Input R d s 2 15in Radius of Shaft A s d s 2 2 Area of shaft Longitudinal Reinforcement n long 24 Number of Longitudinal Bars f y_long 60ksi Yield Strength of Longitudinal Reinforcement A long 0.2in2 Longitudinal Steel Area n long_yield 17 Number of Bars Yielded (Assumption)

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Embedded Pipe A pipe 24in.688 in Cross sectional area of pipe d pipe 16in Inside diameter of pipe f y_pipe 50ksi Yield Strength of Pipe Calculations Using ACI Stress Block at the Point Below the Embedded Pipe 1 f c.85f c 4000psi if .65f c 8000psi if .85.05 f c 4000psi 1000psi 4000psif c 8000psi if 1 f c0.79 ACI 10.2.7.3 A comp n long_yield A long f y_long .85f c A comp 46.35in2 A compcircle h ()R2acos Rh () R Rh ()2R h h2 A comp arootA compcircle h ()h 0in R a3.51in c a 1 f c c4.44in c = 4.35 in. y = 2.9 in. 17 Bars Below Yield Line y.002 c .003 y2.96in

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d bar 9.2502 12.0237 15 17.9763 20.7498 23.1314 25.0189 26.1677 in d bars0 7 id bariA long 2 26.5inA long n long_yield A long d bars 19.13in M n_shaft n long_yield A long f y_long d bars a 2 M n_shaft 295.28ftkip Flexural Capacity of Shaft Flexural Capacity of Pipe Z112in3 Embedded Pipe A pipe 28.5in2 Cross sectional area of pipe d pipe 16in Inside diameter of pipe Pipe wall thickness t pipe 0.47in F y_pipe 42ksi Yield Strength of Pipe Diameter to thickness ratio D_t43.0 Length of the pipe L pipe 3ft E29000ksi Determine Shear Strength of Round HSS L v L pipe 2 F cr_1 max 1.6E () L v d pipe D_t ()5 4 .78E () D_t ()3 2 F cr_1 397.29ksi

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F cr minF cr_1 .6F y_pipe F cr 25.2ksi V n_pipe F cr A pipe 2 V n_pipe 359.1kip Determine Flexural Capacity of Round HSS Check_ApplicableifD_t .45E F y_pipe "Applicable" "N/A" Check_Applicable"Applicable" p .07 E F y_pipe r .31 E F y_pipe Check_Compact"Compact"D_t p if "Noncompact" p D_t r if "Slender"D_t r if Check_Compact"Compact" M p F y_pipe Z M n_pipe M p M n_pipe 392ftkip Flexural Capacity of Pipe Flexural Capacity of T-Plates Using Side-Face Blowout Capacity Flexural Stiffener Plates Width of the stiffener plates b flex_plate 2in Thickness of the stiffener plates t flex_plate 1in Length of the stiffener plates L flex_plate .125 d pipe Length of the shaft L s 36in Diameter of upright/embedded pipe d pipe 16in Diameter of stiffeners d s t d p i p e 2b flex p late

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pp p Concrete Breakout Equivalent Flexural Strength Based on ACI 318 Appendix D c a1 d st 2 23.25 d s 2 2d st 2 2 d st 2 3.25 c a1 3.85in A brg L flex_plate b flex_plate A brg 12.57in2 N sb 200c a1 A brg f c.5 psi.5 N sb 196.22kip M n_blowout N sb d st M n_blowout 327.03ftkip Flexural Capacity of T-Plates Using Side-Face Blowout Capacity Flexural Capacity Using Breakout Capacity Input Width of the stiffener plates b flex_plate 1in Thickness of the stiffener plates t flex_plate 1in Length of the stiffener plates L flex_plate 7in Length of the shaft L s 36in Diameter of upright/embedded pipe d pipe 16in Diameter of stiffeners d st d pipe 4in Number of stiffeners No_Stiff4 Concrete Breakout Equivalent Flexural Strength Based on ACI 318 Appendix D Design requirements for shear loading cover d s d st 2 cover5in c a1 d st 2 23.25 d s 2 2d st 2 2 d st 2 3.25 c a1 3.85in A 360deg No_Stiff A90deg chord_group2 d s 2 sin A 2 chord_group21.21in

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A min_group 2asin 3.0c a1 d s A min_group 45.24deg Check_Group_Effect"Group Effect"AA min_group if "No Group Effect"otherwise Check_Group_Effect"No Group Effect" l breakout t flex_plate 21.5c a1 l breakout 12.54in A Vc minl breakout L s 3 c a1 A Vc 144.67in2 A Vco 4.5c a12 A Vco 66.57in2 l e L flex_plate l e 7in V b 13 l e t flex_plate .2 b flex_plate in f c psi c a1 in 1.5 lbf V b 10.41kip V cbg A Vc A Vco ecV edV cV V b V cbg 31.68kip V cbg_parallel 2V cbg V cbg_parallel 63.37kip V c V cbg_parallel No_Stiff V c 253.47kip M n_breakout V c d st 2 M n_breakout 211.23ftkip Flexural Capacity Using Breakout Capacity M n_bolt 82.83ftkip M n_pipe 392ftkip M n_shaft 295.28ftkip M n_blowout 327.03ftkip M n_breakout 211.23ftkip

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FAILURE EQUATIONS Torsion Threshold Torsion A cp d s 2 2 706.86in2 p cp d s 94.25in T threshold f c psi psi A cp2 p cp T threshold 31.79ftkip ACI 11.6.1a Cracking Torsion T cr 4 f c psi psi A cp2p cp T cr 127.16ftkip ACI R11.6.1 Nominal Torsional Strength A o d h 2 2 572.56in2 A t d hoop 2 2 0.11in2 45deg 0.79rad T torsion 2A o A t f y_hoop s hoop cot () T torsion 252.95ftkip ACI 318-05 11.6.3.6 (11-21) T n_shaft T torsion T n_shaft 252.95ftkip ACI 318-05 11.6.3.5 (11-20) Torsion T n_breakout_plate 337.64ftkip T n_blowout 507.17ftkip T n_shaft 252.95ftkip

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DEVELOPMENT LENGTHS OF FLEXURAL REINF. Development Length of Longitudinal Bars Input Longitudinal Steel A long 0.2in2 Longitudinal Steel Area d long 0.5in Longitudinal Steel Diameter f y_long 60ksi Yield Strength of Longitudinal Steel Development Length of Longitudinal Reinforcement t 1.3 ACI 318-05 12.5.2 e 1.0 s 1.0 1.0 Cb_Ktr2.5in ACI 318-05 12.2.3 l dh_long 3 40 f y_long f c psi psi t e s Cb_Ktr d long d long l dh_long 8.13in ACI 318-05 12.2.3 l d_long l dh_long l d_long 8.13in ACI 318-05 12.2.5 l d_l ceil l d_long in in l d_l 9in Development Length of Longitudinal Bars Length of Shaft Required Length of Stiffeners L7in Length of Breakout l breakout 12.54in Length of Shaft L s 36in Development Length of Longitudinal Reinforcement l d_l 9in Required Cover c_cover2.5in

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Required Length of Shaft Based on Breakout and Development Length l shaft l breakout c_cover l d_l l shaft 24.04in Check_Shaft_LengthifL s l shaft "Sufficient" "Not Sufficient" Check_Shaft_Length"Sufficient" Length of Shaft Required SUPERSTRUCTURE Superstructure Assembly Strength Pipes Superstructure Test Assembly Pipe Pipe Properties HSS 16x.500 Design Wall Thickness t pipe .465in Cross Sectional Area of Pipe A pipe 22.7in2 Diameter to Wall Thickness Ratio D_t34.4 Nominal Weight W pipe 82.85 lbf ft Moment of Inertia I pipe 685in4 Elastic Section Modulus S pipe 85.7in3 Radius of Gyration r pipe 5.49in Plastic Section Modulus Z pipe 112in3 Diameter of the Pipe D pipe 20in Torsional Constant J pipe 1370in4 HSS Torsional Constant C pipe 171in3 Yield Strength F y_pipe 42ksi Ultimate Strength F u_pipe 58ksi Modulus of Elasticity E29000ksi Length of Short Superstructure Pipe L s_pipe 17in Length of Long Superstructure Pipe L l_pipe 9ft

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Short PipeDesign Flexural Strength b flexure .9 AISC Spec. F1 M n_s_pipe F y_pipe Z pipe D_t.45 E F y_pipe if "Equation Invalid"otherwise M n_s_pipe 392ftkip AISC Spec. F2.1 Design Shear Strength b shear .9 AISC Spec. G1 F cr 1.60E () L s_pipe D pipe D_t ()1.25 1.60E () L s_pipe D pipe D_t ()1.25 .78E () D_t ()1.5 if .78E () D_t ()1.5 otherwise F cr_shear minF cr .6F y_pipe F cr_shear 25.2ksi V n_s_pipe b shear F cr_shear A pipe 2 V n_s_pipe 257.42kip AISC Spec. G6 Design Torsional Strength b torsion .75 AISC Spec. H3.1 F cr 1.23E () L s_pipe D pipe D_t ()1.25 1.23E () L s_pipe D pipe D_t ()1.25 .60E () D_t ()1.5 if .60E () D_t ()1.5 otherwise F cr_torsion minF cr .6F y_pipe F cr_torsion 25.2ksi T n_s_pipe F cr_torsion C pipe T n_s_pipe 359.1ftkip AISCSpecH31

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AISC Spec H3 1 Design Axial Strength b comp .90 r .31 E F y_pipe r 214.05 p .07 E F y_pipe "Compact"D_t p if "Noncompact" p D_t r if "Slender"D_t r if "Compact" AISC Spec. B4 k s_pipe .5 F e_short 2E k s_pipe L s_pipe r pipe 2 F e_short 1.19105 ksi AISC Equation E3-4 F cr_short .658F y_pipe F e_short F y_pipe F e_short .44F y_pipe if .877F e_short F e_short .44F y_pipe if P n_s_pipe b comp F cr_short A pipe P n_s_pipe 857.93kip AISC Equation E3-1 Summary for Short Pipe Flexural Strength M n_s_pipe 392ftkip Shear Strength V n_s_pipe 257.42kip Torsional Strength T n_s_pipe 359.1ftkip Axial Strength P n_s_pipe 857.93kip

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Long PipeDesign Flexural Strength b flexure 0.9 AISC Spec. F1 M n_l_pipe b flexure F y_pipe Z pipe D_t.45 E F y_pipe if "Equation Invalid"otherwise M n_l_pipe 352.8ftkip AISC Spec. F2.1 Design Shear Strength b shear 0.9 AISC Spec. G1 F cr 1.60E () L l_pipe D pipe D_t ()1.25 1.60E () L l_pipe D pipe D_t ()1.25 .78E () D_t ()1.5 if .78E () D_t ()1.5 otherwise F cr_shear minF cr .6F y_pipe F cr_shear 25.2ksi V n_l_pipe b shear F cr_shear A pipe 2 V n_l_pipe 257.42kip AISC Spec. G6 Design Torsional Strength b torsion 0.75 AISC Spec. H3.1 F cr 1.23E () L l_pipe D pipe D_t ()1.25 1.23E () L l_pipe D pipe D_t ()1.25 .60E () D_t ()1.5 if .60E () D_t ()1.5 otherwise F cr_torsion minF cr .6F y_pipe F cr_torsion 25.2ksi T n_l_pipe F cr_torsion C pipe T n_l_pipe 359.1ftkip AISC Spec. H3.1

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Design Axial Strength b comp .90 r .31 E F y_pipe r 214.05 p .07 E F y_pipe "Compact"D_t p if "Noncompact" p D_t r if "Slender"D_t r if "Compact" AISC Spec. B4 k long_pipe 2.0 F e_long 2E k long_pipe L l_pipe r pipe 2 F e_long 184.9ksi AISC Equation E3-4 F cr_long .658F y_pipe F e_long F y_pipe F e_long .44F y_pipe if .877F e_long F e_long .44F y_pipe if P n_l_pipe b comp F cr_long A pipe P n_l_pipe 780.24kip AISC Equation E3-1 Summary for Long Pipe Flexural Strength M n_l_pipe 352.8ftkip Shear Strength V n_l_pipe 257.42kip Torsional Strength T n_l_pipe 359.1ftkip Axial Strength P n_l_pipe 780.24kip Superstructure Assembly Strength Pipes

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Superstructure Assembly Strength Connecting Plates Superstructure Test HSS Connection Plate Plate Properties PL1/2" x 32" x 24" Plate thickness t p .5in Plate length h p 32in Plate width b p 24in Yield strength F y_plate 50ksi Ultimate strength F u_plate 62ksi Design Tensile Strength b t_yield .9 P n_yield b t_yield F y_plate t p b p P n_yield 540kip AISC Spec. D2a U1.0 AISC Table D3.1 A n t p b p AISC D3.2 A e UA n A e 12in2 AISC D3.3 b t_rupt .75 P n_rupture b t_rupt A e F u_plate P n_rupture 558kip P n_plate minP n_yield P n_rupture P n_plate 540kip AISC D2b

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Design Flexural Strength b flexure 0.9 A g t p b p A g 12in2 L b 16in I p b p t p3 3 c t p 2 S p I p c S p 4in3 M y S p F y_plate M y 16.67ftkip Z p t p b p 2 t p 2 Z p 1.5in3 M p F y_plate Z p M p 6.25ftkip M p_yield 1.6M y 1.6M y M p if M p otherwise M p_yield 6.25ftkip LTB_Equation_Check"Equation F11-2" .08E () F y_plate L b b p t p2 1.9E () F y_plate if "Equation F11-3" L b b p t p2 1.9E () F y_plate if LTB_Equation_Check"Equation F11-3" C b 1.0 AISC F1 F cr 1.9E C b L b b p t p2 F cr 35.87ksi M n_ltb F cr S p LTB_Equation_Check"Equation F11-3" = if C b 1.52.274L b b p t p2 F y_plate E kip in otherwise M n_ltb 11.96ftkip M n_plate b flexure M n_ltb M n_ltb M p_yield if M p_yield otherwise M n_plate 5.62ftkip

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Design Torsional Strength b torsion 0.75 M t_plate b torsion F y_plate .6 M t_plate 22.5ksi Summary for Plate Connector Tensile Strength P n_plate 540kip Flexural Strength M n_plate 5.62ftkip M t_plate 22.5ksi Torsional Strength Weld Design V weld T n_blowout Tors_Moment_Arm V weld 56.35kip t p 0.5in t pipe 0.47in Weld_Size 3 16 in AISC Spec. J2 Table J2.4 F electrode 70ksi F W .6F electrode AISC Spec. J2 Table J2.5 b weld .75 Throat.707Weld_Size b R n_weld b weld Throat F W b R n_weld 4.18 kip in b R n_yield .6F y_pipe t p b R n_yield 12.6 kip in b R n_rupture .45F u_pipe t p b R n_rupture 13.05 kip in b R n min b R n_weld b R n_yield b R n_rupture b R n 4.18 kip in Required_Length_Each_Side V weld b R n Required_Length_Each_Side13.5in ceil Required_Length_Each_Side in in 14in Superstructure Assembly Strength Connecting Plates

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Base Connection Superstructure Test Base Connection Plate Plate Properties Annular Plate Plate diameter B p 24in Yield strength f y_ann 50ksi Ultimate strength f u_ann 75ksi Thickness of plate t plate 1.00in Bolt Properties D1" ASTM A325 Center to Center Radius of Bolts r b 12in Number of Bolts No_Bolts12 Field Strength of Bolts f y_bolt_field 55ksi Ultimate Strength of Bolts f u_bolt 105ksi Radius of the pipe r p D pipe 2 10in Diameter of the bolt d bolt 1.50in Bolt Bearing Strength L c B p d b .5d bolt 2 1.62in b shear .75 b R n 1.2F u_plate L c t plate b R n 120.9kip Rn_parallel2 b R n Rn_parallel241.8kip T n_bolt_bearing No_BoltsRn_parallel d b 2 T n_bolt_bearing 2.42103 ftkip Check_Bolt_Bearing"Sufficient Strength"T n_bolt_bearing T n_blowout if "Insufficient Strength"otherwise Check_Bolt_Bearing"Sufficient Strength" Check Bolt Spacing s req 2.67d bolt 4in s actual d b 12 5.24in Check_Bolt_Spacing"Sufficient"s actual s req if "Insufficient"otherwise Check_Bolt_Spacing"Sufficient"

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Check Bolt Shear A b .5d bolt 2 1.77in2 F nv .4120 ksi48ksi b V n b shear A b F nv b V n 63.62kip V n_parallel b V n 2 V n_parallel 127.23kip T bolt_shear No_BoltsV n_parallel d b 2 T bolt_shear 1.27103 ftkip Check_Bolt_Shear"Sufficient Strength"T bolt_shear T n_blowout if "Insufficient Strength"otherwise Check_Bolt_Shear"Sufficient Strength" Weld Design Weld Connecting Annular Plate to Pipe t pipe 0.47in Weld_Size 3 8 in AISC Spec. J2 Table J2.4 F electrode 70ksi F W .6F electrode AISC Spec. J2 Table J2.5 Throat.707Weld_Size R n_weld ThroatF W R n_weld 11.14 kip in R n_yield .6F y_pipe t pipe R n_yield 11.72 kip in R n_rupture .45F u_pipe t pipe R n_rupture 12.14 kip in R n minR n_weld R n_yield R n_rupture R n 11.14 kip in R weld R n d pipe R weld 559.72kip T weld R weld d pipe 2 T weld 373.15ftkip M weld R weld d pipe 2 M weld 373.15ftkip Base Connection

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T n_s_pipe 359.1ftkip T weld 373.15ftkip M weld 373.15ftkip CONCRETE BLOCK Concrete Block Design Strut-and-Tie Model Mmax Tension Tie Compression Struts R 6'-0" 4" 4" 9'-6" 10'-0" 6" 5'-0" 6'-0" Based on ACI 318 Appendix A V max T n_breakout_plate Tors_Moment_Arm V max 37.52kip M max V max Flex_Moment_Arm M max 300.13ftkip d6ft8in d80in R M max d R45.02kip Node A atan5 ft d 36.87deg C R sin () C75.03kip

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TCcos () T60.03kip Check Reinforcement No_Bars_Block_Reinf3 Block_Reinf_Bar_No8 f y_block_reinf 60ksi A block_reinf No_Bars_Block_Reinf Block_Reinf_Bar_No8 2 2 in2 A block_reinf 2.36in2 Check_Block_Reinf_A"Sufficient"A block_reinf f y_block_reinf T if "Not Sufficient"otherwise Check_Block_Reinf_A"Sufficient" Concrete Block Design Strut-and-Tie Model Concrete Block Design Beam Theory R 4" 3'-0" 4'-9" 5'-0" Vblock M V block R V block 45.02kip M block R3ft4in () M block 150.06ftkip From strut-and-tie model... A block_reinf 2.36in2

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f y_block_reinf 60ksi Check Shear Check_Shear_B"Sufficient"A block_reinf f y_block_reinf V block if "Insufficient"otherwise Check_Shear_B"Sufficient" Check Flexure b block 30in h block 6ft d block 5.5ft T given A block_reinf f y_block_reinf T given 141.37kip Ca ().85f c b block a Pa ()Ca()T given arootPa ()a 0in h block a1.07in 1 f c0.79 c a 1 f c c1.35in M n_block T given d block a 2 M n_block 771.24ftkip Check_Flexure_B"Sufficient"M n_block M block if "Insufficient"otherwise Check_Flexure_B"Sufficient" Required Hook Length for a #8 bar Hook_No_812 Block_Reinf_Bar_No 8 in Hook_No_812in ACI 318-05 Fig. 12.5 Concrete Block Design Beam Theory Summary of Concrete Block Reinforcement Block_Reinf_Bar_No8 No_Bars_Block_Reinf3 Check_Block_Reinf_A"Sufficient" Check_Shear_B"Sufficient" Check_Flexure_B"Sufficient" Summary of Concrete Block Reinforcement

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Tie-Down Design Block Properties Width of the block b block 30in Height of the block h block 6ft Length of the block l block 10ft Diameter of the shaft d s 30in Length of the shaft l shaft 36in Weight of concrete w c 150pcf Maximum shear applied V max 37.52kip Channel Assembly 2 C12x30 Channels with 1.75" between Moment of inertia about strong axis I x 162in4 S x 27.0in3 Radius of gyration about strong axis r x 4.29in Z x 33.8in3 Cross sectional area A channel 8.81in2 Moment of inertia about weak axis I y 5.12in4 Radius of gyration about weak axis r y .762in x_bar.674in Yield strength F y_channel 50ksi Modulus of elasticity E2.9104 ksi Web thickness t w .510in Flange width b f 3.17in Flange thickness t f .501in Depth h12in

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7'-4" 8" 5'-4" 8" Vmax R1 W1 W2 1'-3" 2'-6" 3'-0" 8'-9.5" Calculate self-weight of block W 1 h block b block l block w c W 1 22.5kip W 2 l shaft 4 d s2 w c W 2 2.21kip Calculate the Load that the Tie-down must resist in each direction R 1 W 2 l shaft 2 b block W 1 b block 2 V max l shaft 17.5in b block b block R 1 89.63kip R 2 V max L l_pipe 3ft 4in W 1 W 2 3ft4in () 6.67ft R 2 57.02kip

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5'-0" 5'-0" Centerline of Support 4" 4" W1 + W2 Vmax 3'-0" 3'-0" R2 Total Load that the Tie-down must support R R 1 2 R 2 R101.84kip Check that the load is less than the capacity of the floor Floor_Capacity200kip Check_Floor_Capacity"Sufficient"Floor_CapacityR if "Insufficient"otherwise Check_Floor_Capacity"Sufficient" Check Bearing Strength of Concrete Conservatively assume that the load bears on 1 in. of concrete across the length of the block... A bearing l block 1 in A bearing 120in2 b bearing .65 Bearing_Strength b bearing .85 f c A bearing Bearing_Strength343.3kip Check_Bearing_Capacity"Sufficient"Bearing_Strength2R if "Insufficient"otherwise Check_Bearing_Capacity"Sufficient"

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7'-4" 8" 5'-4" 8" Rr Rl Papp Required Capacity of the Channel Assembly P app R P app 101.84kip R L P app 2 ft 6ft R L 33.95kip R R P app R L R R 67.89kip a4ft b2ft M max_tiedown P app a b ab M max_tiedown 135.79ftkip Flexural Capacity of Each Channel M n_tiedown F y_channel 2Z x M n_tiedown 281.67ftkip AISC Spec. F2.1 (F2-1) Check_Flexure_Channels"Sufficient"M n_tiedown M max_tiedown if "Insufficient"otherwise Check_Flexure_Channels"Sufficient" Buckling Check of Each Channel Treated as 2 separate channels f b f 2t f f 3.16 w h t w w 23.53

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pf .38 E F y_channel pf 9.15 AISC Spec. B4 pw 3.76 E F y_channel pw 90.55 AISC Spec. B4 Check_Flange_Compact"Compact" pf f if "Not Compact"otherwise Check_Flange_Compact"Compact" AISC Spec. B4 Check_Web_Compact"Compact" pw w if "Not Compact"otherwise Check_Web_Compact"Compact" AISC Spec. B4 Bracing Check of Each Channel L b b L b 2ft L p 1.76r y E F y_channel L p 2.69ft AISC Spec. F2.2 (F2-5) Bracing_Check"Braced"L p L b if "Unbraced"otherwise Bracing_Check"Braced"

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Checking Channel Assembly I y_unit 2I y A channel x_bar 1.75in 2 2 I y_unit 52.52in4 r y_unit I y_unit A channel r y_unit 2.44in L p_unit 1.76r y_unit E F y_channel L p_unit 103.49in b f_unit 2b f 1.75in b f_unit 8.09in t w_unit 2t w 1.75in t w_unit 2.77in f_unit b f_unit 2t f f_unit 8.07 w_unit h t w_unit w_unit 4.33 Check_Flange_Compact_Unit"Compact" pf f_unit if "Not Compact"otherwise Check_Flange_Compact_Unit"Compact" Check_Web_Compact_Unit"Compact" pw w_unit if "Not Compact"otherwise Check_Web_Compact_Unit"Compact" Bracing_Check_Unit"Braced"L p_unit L b if "Unbraced"otherwise

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Bracing_Check_Unit"Braced" Weld Design V weld maxR L R R V weld 67.89kip t pl .5in b pl 5in Qt pl b pl t pl 2 h 2 Q15.62in3 I weld 2I x 2t pl b pl t pl 2 h 2 2 1 12 b pl t pl3 I weld 519.42in4 Required_Load_per_Foot V weld Q I weld Required_Load_per_Foot24.51 kip ft Weld_Size 3 8 in F electrode 70ksi F W .6F electrode 42ksi AISC Spec. J2 Table J2.5 b weld .75 Throat.707Weld_Size Required_Length_Per_Foot Required_Load_per_Foot b weld F W Throat Required_Length_Per_Foot2.93 in ft Specify 4" per foot of Weld AISC Spec. J2.4 (J2-3) Tie-Down Design T max T n_breakout_plate 337.64ftkip V max 37.52kip M max 300.13ftkip

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186 APPENDIX C TEST DATA Torsion Test Data Figure C 1. Moment and rotation plot for base plate of torsion test Predicted Maximum Failure Cracks Widen Failure Cracks Form Torsion Cracks Form Bolt Slippage Ends

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187 Figure C 2. Moment and torsional rotation plot for torsion test Rear of Shaft Face of Shaft Outer Base Plate

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188 Torsion and Flexure Test Data Figure C 3. Load and torsional rotation of base plate for torsion and flexure test Bond loosens Torsion and flexure cracks form Failure cracks widen Failure cracks form

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189 Figure C 4. Load and flexural rotation for torsion and flexure test Base plate to rear of shaft Predicted failure Failure cracks widen Base plate to face of shaft Bond loosens Bolt slippage ends Face of shaft to rear of shaft

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190 Figure C 5. Load and torsional rotation for torsion and flexure test Face of shaft Base plate Rear of shaft

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191 APPENDIX D DESIGN GUIDELINES For the purposes of these design guidelines, the design of a typical sign/signal can be divided into three areas. The first of these would be the superstructure, which would include the vertical column, horizontal member, connection between the horizontal and vertical members, and any other design components above the base connection. The second design area would be the interface with the foundation or the base connection. This second design area can be subdivided into the superstructure interface and the f oundation interface. The last of the design areas would be the foundation. These design guidelines will only cover the base connection and the foundation. It is assumed that the superstructure will be designed appropriately using other FDOT design guidelines. The FDOT offers a MathCAD worksheet program called MastArm v4.3 on their website that includes the design of the superstructure including the horizontal arm, connection to the vertical column, the vertical column, and the annular base plate. For the c oncerns of this design guideline the interface with the foundation and the foundation will need to be designed for shear, torsion, and flexure. The foundation interface will need to be designed to match the annular base plate from the MastArm v4.3 output a nd the connecting bolts and welds will need to be designed. The foundation will need to have the embedded steel pipe and plates, their welded connections, the concrete, and the concrete reinforcement designed. A design example will be displayed on the foll owing pages. Base Connection Design For the design recommended in these design guidelines the information obtained from the MastArm v4.3 program will be the basis for the design. See Figure D 1 for a clarification of terminology. For the design of the base plate, the designer will need the following information from the FDOT program or their own design:

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192 Design loads for shear, flexure, and torsion ( Vu, Tu, and Mu) Superstructure interface base plate sized The designer should then use this information and their own design knowledge to design the following for the base connection: Size the foundation interface base plate to match the superstructure inter face base plate Size the leveling bolts for design shear, flexure, and torsion Ensure shear capacity of bolt holes exceeds design shear Size the leveling nuts Embedded Pipe Design For the design of the embedded pipe, the designer will need the following information from the FDOT program or their own design: Design loads for shear, flexure, and torsion ( Vu, Tu, and Mu) Superstructure monopole sized Welded connection from superstructure monopole to superstructure interface base plate sized The designer shoul d then use this information and their own design knowledge to design the following for the embedded pipe: Size the cross section of the embedded pipe to have the same diameter and wall thickness as the superstructure monopole. The embedded pipe can be either a tapered section or an HSS pipe. Size the welded connection from the embedded pipe to the foundation interface base plate to be the same as the welded connection from the superstructure monopole to the superstructure interface base plate. Embedded Pipe and Torsion Plates Design For the design of the torsion plates, the designer will need the following information from the FDOT program or their own design: Design loads for shear, flexure, and torsion ( Vu, Tu, and Mu) Diameter and length of the circular pedestal portion of the concrete foundation Specified concrete strength of the circular pedestal portion of the concrete foundation Cross section geometry of the embedded pipe

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193 The designer should then use this information and their own design kno wledge to design the following for the embedded pipe and plate section (See Figure D 2): Determine the number of torsion plates by engineering judgment (minimum of 4, Ntorsion plates) Determine the length of torsion plates by engineering judgment (minimum of 6 inches) Determine width and thickness of torsion plates by engineering judgment (minimum of 1 inch for each) Determine the breakout edge distance, ca1 Determine the angle available for each plate to breakout Determine the angle required for group effect Check group effect. If group effect present, reduce the number of plates or diameter of shaft until no group effect occurs. Determine length of breakout Determine breakout area of one plate Determine breakout area of equivalent anchor bolt Determine basic shear strength of one torsional plate Determine the breakout strength of one torsional plate

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194 Determine the breakout strength of the system of torsional plates Determine the torsional strength of the system of plates Check to ensure that the Tn breakout is greater than Tu Ba sed on the breakout length above, choose depth of embedment for pipe the breakout should not reach the surface of the concrete Size welds to handle design loads (AASHTO LRFD Bridge Design Specifications Section 6.13.3.2.4) Embedded Pipe and Flexure Plate Design For the design of the flexural plate, the designer will need the following information from the FDOT program or their own design: Design loads for shear, flexure, and torsion ( Vu, Tu, and Mu) Diameter and length of the circular pedestal portion of the foundation Specified compressive strength of concrete Embedded pipe dimensions The designer should then use this information and their own design knowledge to design the following for the embedded pipe and plate section (See Figure D 3): Assume the nu mber of idealized flexural bearing positions on flexure plate is 2 Determine thickness of flexure plate, minimum of 1 inch Determine diameter of flexure plate, minimum of 2 inches greater than embedded pipe outside diameter (maintain aspect ratio of width to thickness less than 2:1 to avoid prying action) Determine the breakout edge distance, ca1 Determine the angle available for each plate to breakout

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195 Determine the angle required for group effect Check group effect. If group effect present, reduce the number of plates or diameter of shaft until no group effect occurs. Determine length of breakout Determine breakout area of one plate Determine breakout area of equivalent anchor bolt Determine basic shear strength of one torsional plate Determine the breakout strength of one torsional plate Determine the breakout strength of the system of torsio nal plates Determine the torsional strength of the system of plates Check to ensure that the Mn breakout is greater than Mu Based on the breakout length above, verify depth of embedment for pipe the breakout should not reach the surface of the concrete Size welds to handle design loads (AASHTO LRFD Bridge Design Specifications Section 6.13.3.2.4)

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196 Concrete Pedestal Reinforcement For the design of the concrete pedestal reinforcement, the designer will need the following information from the FDOT program or their own design: Design loads for shear, flexure, and torsion ( Vu, Tu, and Mu) Diameter and length of the circular pedestal portion of the foundation Specified compressive strength of concrete The designer should then use this information and their own design knowledge to design the following for the embedded pipe and plate section : Reinforcemen t for flexure (AASHTO LRFD Bridge Design Specifications Section 5.7.3.2.4) Reinforcement for torsion (AASHTO LRFD Bridge Design Specifications Equation 5.8.3.6.21)

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197 Figure D 1. Depiction of the elements described in the design guidelines Superstructure monopole Welded connection Superstructure interface base plate Bolted connection Foundation interface base plate Concrete foundation Torsional reinforcement Flexural plate Embedded pipe and plate section Flexural reinforcement Torsional plate Welded connection Leveling nut Superstructure Base Connection Foundation

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198 Figure D 2. Depiction of dimensions required for torsion plate design 3.0c a1 +l pl V b c a1 A Vcp 1.5c a1 1.5c a1 3.0c a1 +l pl 1.5c a1 1.5c a1 c a1 Length of torsion plates Width of torsion plates Thickness of torsion plates

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199 Figure D 3. Depiction of dimensions required for flexure plate design 3.0c a1 +t fp 1.5c a1 1.5c a1 c a1 Width of flexure plate 3.0c a1 +t fp l e 1.5c a1 1.5c a1 A Vcp l e V bfp Thickness of flexure plate Length of bearing area

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Sample Design GuidelinesGuidelines for the Design of the Embedded Pipe and Plate Section The guidelines presented below are intended ONLY to design the embedded pipe and plate section. The remainder of the design should be designed according to applicable FDOT and AASHTO design guidelines. Input from MastArm Program v4.3 Design Loads Derived using an example from FDOT Program MastArm Program v4.3 V u 1.21.04 kip1.64.87 kip 9.04kip T u V u 22 ft198.88kipft M u 1.218.33 kipft 1.689.59 kipft 165.34kipft Foundation Geometry Derived using an example from FDOT Program MastArm Program v4.3 L shaft 12ft Diameter base.pole 16in t wall.pole .375in Diameter baseplate.pole 30in t baseplate.pole 1.63in Diameter shaft 3.5ft Diameter boltcircle.pole 23in Diameter rebar.circle 27.7in No long.rebar 11 Diameter long.rebar 1.27in Input from MastArm Program v4.3 Base Connection Design Step 1) Base Connection DesignGiven flex .9 Diameter base.pole 16in f y.pipe 42ksi t wall.pole 0.375in f u.pipe 58ksi Diameter baseplate.pole 30in f y.baseplate 36ksi t baseplate.pole 1.63in f u.baseplate 58ksi Diameter boltcircle.pole 23in E s 29000ksi

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V u 9.04kip T u 198.88ftkip M u 165.34ftkip Size the foundation interface base plate Diameter baseplate.found Diameter baseplate.pole 30in t baseplate.found t baseplate.pole 1.63in Size the bolts for design shear, flexure, and torsion Using threaded rods with A36 steel F y.threadedrod 36ksi F u.threadedrod 58ksi F nt.threadedrod .75F u.threadedrod 43.5ksi AISC Table J3.2 F nv.threadedrod .4F u.threadedrod 23.2ksi AISC Table J3.2 Select the number of bolts to use Number threadedrod 12 Determine the required diameter of bolts for torsion resolved into shear V required T u Number threadedrod Diameter boltcircle.pole 8.647kip A threadedrod.tors V required F nv.threadedrod 0.373in2 Diameter threadedrod.tors 4A threadedrod.tors 0.689in Round up to the nearest 1/8" Diameter threadedrod.tors CeilDiameter threadedrod.tors 1 8 in Diameter threadedrod.tors 0.75in Determine the required diameter of bolts for flexure resolved into tension P required M u Diameter boltcircle.pole 86.264kip A threadedrod.flex P required F nt.threadedrod 1.983in2 Diameter threadedrod.flex 4A threadedrod.flex 1.589in Round up to the nearest 1/8" Diameter threadedrod.flex CeilDiameter threadedrod.flex 1 8 in Diameter threadedrod.flex 1.625in

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Determine the required diameter of bolts for shear A threadedrod.shear V u F nv.threadedrod 0.39in2 Diameter threadedrod.shear 4A threadedrod.shear 0.704in Round up to the nearest 1/8" Diameter threadedrod.shear CeilDiameter threadedrod.shear 1 8 in Diameter threadedrod.shear 0.75in Use the controlling diameter Diameter threadedrod maxDiameter threadedrod.tors Diameter threadedrod.flex Diameter threadedrod.shear Diameter threadedrod 1.625in Determine the length of the threaded rod after determining the size of the nuts and washers Check minimum spacing and edge distance s threadedrod Diameter boltcircle.pole Number threadedrod 6.021in s min 8 3 Diameter threadedrod 4.333in AISC J3.3 Check_spacingifs threadedrod s min "Sufficient" "Not Sufficient" Check_spacing"Sufficient" L c.threadedrod Diameter baseplate.pole Diameter boltcircle.pole 2 3.5in L min 1.75Diameter threadedrod 2.844in AISC Table J3.4 Check_edgedistifL c.threadedrod L min "Sufficient" "Not Sufficient" Check_edgedist"Sufficient" Check bearing strength of bolt holes P n.bolthole 1.2L c.threadedrod t baseplate.pole f u.baseplate 397.068kip P max.bolthole 2.4Diameter threadedrod t baseplate.pole f u.baseplate 368.706kip Check_bearingifP n.bolthole P max.bolthole "Sufficient" "Not Sufficient" Check_bearing"Not Sufficient"

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Increase threaded rod diameter to 2 in Diameter threadedrod 2in P max.bolthole 2.4Diameter threadedrod t baseplate.pole f u.baseplate 453.792kip Check_bearingifP n.bolthole P max.bolthole "Sufficient" "Not Sufficient" Check_bearing"Sufficient" Size the leveling nuts Use Heavy Hex nuts W level.nut 3.125in AISC Table 7-20 C level.nut 3.625in AISC Table 7-20 AISC Table 7-20 N level.nut 2in AISC Table 7-20 Base Connection Design Embedded Pipe Design Step 2) Embedded Pipe DesignGiven flex 0.9 Diameter base.pole 16in weld .75 t wall.pole 0.375in f y.pipe 42ksi Diameter baseplate.pole 30in f u.pipe 58ksi t baseplate.pole 1.63in f y.baseplate 36ksi Diameter boltcircle.pole 23in f u.baseplate 58ksi E s 2.9104 ksi V u 9.04kip T u 198.88ftkip M u 165.34ftkip Size the cross section of the embedded pipe Diameter embed.pipe Diameter base.pole 16in t wall.embed.pipe t wall.pole 0.375in

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Size the welded connection from the embedded pipe to the foundation base plate V weld.reqd maxV u T u Diameter embed.pipe 149.16kip Select weld properties and revise if necessary Weld_Size 1 4 in AISC Spec. J2 Table J2.4 F electrode 70ksi F W .6F electrode AISC Spec. J2 Table J2.5 Throat.707Weld_Size R n_weld weld Throat F W R n_weld 5.568 kip in R n_yield .6f y.pipe t wall.embed.pipe R n_yield 9.45 kip in R n_rupture .45f u.pipe t wall.embed.pipe R n_rupture 9.787 kip in R n min R n_weld R n_yield R n_rupture R n 5.568 kip in Required_Length_Plate V weld.reqd R n Required_Length_Plate26.791in CeilRequired_Length_Plate1in ()27in Check_Length"Sufficient" Diameter embed.pipe Required_Length_Plate if "Not Sufficient"otherwise Check_Length"Sufficient" Embedded Pipe Design Embedded Pipe and Torsion Plates Design Step 3) Embedded Pipe and Torsion Plates DesignGiven flex 0.9 Diameter embed.pipe 16in weld 0.75 tor .9 t wall.embed.pipe 0.375in f y.pipe 42ksi f u.pipe 58ksi Diameter shaft 42in

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L shaft 12ft E s 2.9104 ksi f' c 5500psi V u 9.04kip T u 198.88ftkip L breakout Avc M u 165.34ftkip Based on ACI 318-08 Appendix D Anchorage to Concrete Estimate torsion plate section properties and refine if necessary N tor.plate 4 Number of torsion plates, minimum of 4 L tor.plate 6in Length of torsion plate, minimum of 6 in. b tor.plate 1in Width of torsion plate, minimum of 1 in. t tor.plate 1in Thickness of torsion plate, minimum of 1 in. cover Diameter shaft Diameter embed.pipe 2 cover13in c a1 Diameter embed.pipe 2 23.25 Diameter shaft 2 2Diameter embed.pipe 2 2 Diameter embed.pip e 2 3.25 c a1 8.587in A 360deg N tor.plate 1.571 A90deg

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chord_group2 Diameter shaft 2 sin A 2 chord_group2.475ft A min_group 2asin 3.0c a1 Diameter shaft A min_group 75.66deg Check_Group_Effect"Group Effect"AA min_group if "No Group Effect"otherwise Check_Group_Effect"No Group E f L breakout L tor.plate 21.5c a1 L breakout 31.76in A Vc minL breakout L shaft 3 c a1 A Vc 818.109in2 A Vco 4.5c a12 A Vco 331.776in2 l e L tor.plate l e 0.5ft V b 13 l e b tor.plate .2 b tor.plate in f' c psi c a1 in 1.5 lbf V b 34.712kip cV 1.4 Modification factor for cracking in concrete ecV 1.0 Modification factor for anchor groups edV 1.0 Modification factor for edge effects V cbg A Vc A Vco ecV edV cV V b V cbg 119.832kip V cbg_parallel 2V cbg V cbg_parallel 239.664kip V c V cbg_parallel N tor.plate V c 958.658kip T n.breakout.plate tor V c Diameter embed.pipe 2 T n.breakout.plate 575.195ftkip Check_Breakout_Torsion"Sufficient"T n.breakout.plate T u if "Not Sufficient"T n.breakout.plate T u if Check_Breakout_Torsion"Sufficient" Based on breakout length above, choose depth of embedment for pipe L clearance 3in Length of clearance between breakout and top of shaft

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L embedment L clearance L breakout 1.5c a1 L embedment 21.88in L embedment ceil L embedment in in L embedment 22in Weld Design for Torsion Plates V weld.tor T n.breakout.plate Diameter shaft V weld.tor 164.341kip Select weld properties and revise if necessary Weld_Size 3 8 in AISC Spec. J2 Table J2.4 F electrode 70ksi F W .6F electrode AISC Spec. J2 Table J2.5 Throat.707Weld_Size R n_weld weld Throat F W R n_weld 8.351 kip in R n_yield .6f y.pipe t wall.embed.pipe R n_yield 9.45 kip in R n_rupture .45f u.pipe t wall.embed.pipe R n_rupture 9.787 kip in R n min R n_weld R n_yield R n_rupture R n 8.351 kip in Required_Length_Each_Plate V weld.tor N tor.plate R n Required_Length_Each_Plate4.92in ceil Required_Length_Each_Plate in in 5in Check_Length"Sufficient"L tor.plate Required_Length_Each_Plate if "Not Sufficient"otherwise Check_Length"Sufficient" Embedded Pipe and Torsion Plates Design

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Embedded Pipe and Flexure Plate Design Step 4) Embedded Pipe and Flexure Plate DesignGiven Given flex 0.9 Diameter embed.pipe 16in weld 0.75 t wall.embed.pipe 0.375in tor 0.9 Diameter shaft 42in f y.pipe 42ksi L shaft 12ft f u.pipe 58ksi f' c 5.5ksi E s 2.9104 ksi V u 9.04kip T u 198.88ftkip M u 165.34ftkip Based on ACI 318-08 Appendix D Anchorage to Concrete Estimate flexure plate section properties and refine if necessary N flex.plate.bear 4 Number of idealized flexural bearing positions on flexure plate t flex.plate 1in Thickness of flexure plate, minimum of 1 in. Diameter flex.plate 20in Diameter of flexure plate, minimum of 2 in. greater than embedded plate cover Diameter shaft Diameter flex.plate 2 cover11in c a1 Diameter flex.plate 2 23.25 Diameter shaft 2 2Diameter flex.plate 2 2 Diameter flex.plate 2 3.25 c a1 7.618in A 360deg N flex.plate.bear 1.571 A90deg chord_group2 Diameter shaft 2 sin A 2 chord_group2.475ft A min_group 2asin 3.0c a1 Diameter shaft A min_group 65.936deg Check_Group_Effect"Group Effect"AA min_group if "No Group Effect"otherwise Check_Group_Effect"No Group E f

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L breakout t flex.plate 21.5c a1 L breakout 23.855in A Vc minL breakout L shaft 3 c a1 A Vc 545.219in2 A Vco 4.5c a12 A Vco 261.182in2 b flex.plate .5Diameter flex.plate Diameter embed.pipe b flex.plate 2in L flex.plate 8 Diameter embed.pipe 2.5 b flex.plate L flex.plate 7.069in l e L flex.plate l e 7.069in V b 13 l e t flex.plate .2 b flex.plate in f' c psi c a1 in 1.5 lbf V b 42.394kip cV 1.4 Modification factor for cracking in concrete ecV 1.0 Modification factor for anchor groups edV 1.0 Modification factor for edge effects V cbg A Vc A Vco ecV edV cV V b V cbg 123.897kip V cbg_parallel 2V cbg V cbg_parallel 247.794kip V c V cbg_parallel .5 N flex.plate.bear V c 495.587kip M n.breakout.plate tor V c Diameter embed.pipe 2 M n.breakout.plate 297.352ftkip Check_Breakout_Flexure"Sufficient"M n.breakout.plate T u if "Not Sufficient"M n.breakout.plate T u if Check_Breakout_Flexure"Sufficient" Weld Design for Flexure Plate V weld.flex maxM u M n.breakout.plate Diameter flex.plate V weld.flex 178.411kip Select weld properties and revise if necessary Weld_Size 1 4 in AISC Spec. J2 Table J2.4 F electrode 70ksi

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F W .6F electrode AISC Spec. J2 Table J2.5 Throat.707Weld_Size R n_weld weld Throat F W R n_weld 5.568 kip in R n_yield .6f y.pipe t wall.embed.pipe R n_yield 9.45 kip in R n_rupture .45f u.pipe t wall.embed.pipe R n_rupture 9.787 kip in R n min R n_weld R n_yield R n_rupture R n 5.568 kip in Required_Length_Plate V weld.flex R n Required_Length_Plate32.044in ceil Required_Length_Plate in in 33in Check_Length"Sufficient" Diameter embed.pipe Required_Length_Plate if "Not Sufficient"otherwise Check_Length"Sufficient" Embedded Pipe and Flexure Plate Design Concrete Pedestal Reinforcement Step 5) Concrete Pedestal ReinforcementGiven Diameter shaft 42in f y.rebar 50ksi L shaft 12ft Diameter hoop.rebar .500in f' c 5.5ksi R.5Diameter shaft 21in V u 9.04kip Diameter flex.rebar 1.375in T u 198.88ftkip Diameter rebar.circle 27.5in M u 165.34ftkip Reinforcement for Flexure Determine properties of flexural reinforcement Number flex.rebar No long.rebar 11 A flex.rebar .25 Diameter flex.rebar2 Assume 8 of the 11 bars yield n flex.yield 8

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Calculations Using ACI Stress Block 1 f c.85f c 4000psi if .65f c 8000psi if .85.05 f c 4000psi 1000psi 4000psif c 8000psi if 1 f' c0.775 ACI 10.2.7.3 A comp n flex.yield A flex.rebar f y.rebar .85f' c A comp 0.882ft2 A compcircle h ()R2acos Rh () R Rh ()2R h h2 A comp arootA compcircle h ()h 0in R a6.191in c a 1 f' c c7.988in y.002 c .003 y5.325in c = 7.988 in. y = 5.325 in. d bars .5Diameter shaft c y c y d bars 27.657in M n.shaft flex n flex.yield A flex.rebar f y.rebar d bars a 2 M n.shaft 1.094103 ftkip Check_FlexureifM n.shaft M u "Sufficient" "Not Sufficient" Check_Flexure"Sufficient"

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Reinforcement for Torsion A tors.rebar .5Diameter hoop.rebar 2 0.196in2 A o .5Diameter rebar.circle .5Diameter long.rebar .5Diameter hoop.rebar 2 672.876in2 s tors.rebar 4in T n.shaft tor 2A o A tors.rebar f y.rebar s tors.rebar cot45deg () T n.shaft 247.723ftkip Check_TorsionifT n.shaft T u "Sufficient" "Not Sufficient" Check_Torsion"Sufficient" Concrete Pedestal Reinforcement

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213 LIST OF R EFERENCES 1. Cook, R.A., and Halcovage, K.M., Anchorage Embedment Requirements for Signal/Sign Structures, Florida Department of Transportation, Tallahassee, FL, 2007, 119 pp. 2. Fouad, F.H.; Davidson, J.S.; Delatte, N.; Calvert, E.A.; Chen, S.; Nunez, E.; and Abdalla, R., Structural Supports for Highway Signs, Luminaires, and Traffic Signals, National Cooperative Highway Research Program Report 494, Transportation Research Board of the National Academies, Washington, D.C., 2003, pp. 316. 3. AASHTO Highway Subcommittee on Bridges and Structures, Standard Specific ations for Structural Supports for Highway Signs, Luminaires, and Traffic Signals, American Association of State Highway and Transportation Officials, Washington, D.C., Fourth Edition, 2001, pp. 131138. 4. Fouad, F.H.; Calvert, E.A., and Nunez, E., Struc tural Supports for Highway Signs, Luminaires, and Traffic Signals: Draft Final Report, Transportation Research Board of the National Academies, Washinton, D.C., September 1997, 170 pp. 5. ACI Committee 318, Building Code Requirements for Structural Concrete (ACI 318 08) and Commentary, American Concrete Institute, Farmington Hills, MI, 2008, 473 pp. 6. Dexter, R.J., and Ricker, M.J., Fatigue Resistant Design of Cantilevered Signal, Sign, and Light Supports, National Cooperative Highway Research Program Repor t 469, Transportation Research Board of the National Academies, Washington, D.C., 2002, pp. 49. 7. Kaczinski, M.R.; Dexter, R.J., and Van Dien, J.P., Fatigue Resistant Design of Cantilevered Signal, Sign, and Light Supports, National Cooperative Highway Re search Program Report 412, Transportation Research Board of the National Academies, Washington, D.C., 1998, pp.119, 56149. 8. Billingstad, N.A., and Volle, F.I., Foundation Tube for use as a Foundation for Mast s Posts, Pillars, etc. 5,836,124 United Stat es, November 17, 1998 (Patent) 9. IEEE Power Engineering Society and the American Society of Civil Engineers, IEEE Guide for Transmission Structure Foundation Design and Testing (IEEE Std 6912001), The Institute of Electrical and Electronics Engineers, Ne w York, New York, 2001. 10. Gates, W., Wind Farms Dynamics: Not all slopes are created equal, Power Engineering International, August 2008, Available from http://pepei.pennet.com/Articles/Article_Display.cfm?ARTICLE_ID=3227637p= 6, Accessed October 31, 2008.a

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214 11. Wind Energy Direct, Tower Guide, Wind Energy Direct, Available from http://www.windenergydirect.org/tower_guide.pdf, Accessed October 31, 2008. 12. Fuchs, W.; Eligehausen, R., and Breen, J., Concrete Capacity Design (CCD) Approach for Fastening to Concret e, ACI Structural Journal, V. 9 2, No. 1, Jan.Feb. 1995, pp. 7394. 13. Furche, J., and Eligehausen, R., Lateral Blow out Failure of Headed Studs Near a Free Edge, Anchors in Concrete Design and Behavior, SP 130, American Concrete Institute, Farmington Hills, MI, 1991, pp. 235252. 14. Bae, S.; Bayrak, O.; Jirsa, J.O., and Klingner, R.E., Effect of Al kali Silica Reaction/Delayed Ettriginite Formation Damage on Behavior of Deeply Embedded Anchor Bolts, ACI Structural Journal, V. 106, No. 6, Nov.Dec. 2009, pp.848857. 15. American Institute of Steel Construction, Steel Construction Manual, American Insti tute of Steel Construction, Chicago, Thirteenth Edition, 2005, 2190 pp. 16. Collins, T.J., and Garlich, M.G., Sign Structures Under Watch, Roads and Bridges, July 1997, Available from http://www.roadsbridges.com/SignStructures under Watch article761, Accessed August 13, 2009. 17. AASHTO Highway Subcommittee on Bridges and Structures, 2006 Interim to Standard Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals, American Association of State Highway and Transportation Offici als, Washington, D.C., 2006, pp. 13113 8. 18. State of Florida, Department of Transportation, Design Standards for Design, Construction, Maintenance, and Utility Operations of the State Highway System, Index No. 11860, Florida Department of Transportation, Tallahassee, FL, pp. 18. 19. Cook, R.A., McVay, M.C., and Canner, I., Alternatives for Precast Pile Splices, Vol. 2 Florida Department of Transportation, Tallahassee, FL, 143 pp.

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215 BIOGRAPHICAL SKETCH Kathryn Jenner was born in Miami, Florida in March 1986 to parents Stuart and Joann Jenner At the age of eight her family relocated to scenic Naples, Florida. In May 2004 Kathryn graduated with high honors from Gulf Coast High School in Naples. She began attending the University of Florida in the fall of 2004. In May 2008 Kathryn graduated cum laude from the University of Florida with a Bachelor of Science in Civil Engineering. She graduated with her Master of Engineering in May 2010.