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Time Dependent Load Response of Flexible Pipe Subjected to Sustained Loading

Permanent Link: http://ufdc.ufl.edu/UFE0042947/00001

Material Information

Title: Time Dependent Load Response of Flexible Pipe Subjected to Sustained Loading
Physical Description: 1 online resource (114 p.)
Language: english
Creator: PASKEN,KENNETH A
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2011

Subjects

Subjects / Keywords: 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: It is crucial to the long term sustainability of roadway drainage systems that manufacturing guidelines are stringent, but reasonable, so as to allow for maximum life efficiency of the selected products. For this reason, the Florida Department of Transportation (FDOT) has contracted the University of Florida (UF) and members of Simpson, Gumpertz, & Heger, Incorporated (SGH) to perform a series of static load tests on a variety of flexible pipe materials used for storm water runoff along Florida highways. The flexible pipe materials consist of High Density Polyethylene (HDPE), Polyvinyl Chloride (PVC), aluminum, and stainless steel. During a loading sequence, there are two pipes of the same material which are lowered into a soil box. The soil box is then backfilled with soil, sealed, and then pressurized, allowing a load to be uniformly distributed to the pipes. The purpose of this testing is to record and collect pressure data from load cells placed at precise locations throughout the soil box. The pressure data, along with deflection data recorded and collected from a displacement laser which runs along a track for the length of each of the two pipes, will provide the input for an FEM analysis to be performed. The FEM analysis is being performed by Timothy J. McGrath, Ph.D., P.E. of SGH. The FEM analysis will allow for a variety of loading situations to be simulated. The results of these analyses will allow for the FDOT to codify a baseline manufacturing guideline for each of the four different pipe materials. To be specific, each pipe is manufactured with a certain amount of pre-deflection. The FDOT is looking to minimize this number so that pipes which are subjected to a variety of loading conditions on a job site will ultimately perform as they are supposed to for their life expectancy, rather than fail prematurely. The scheduled completion date for this project is the third quarter of 2013; therefore, the information presented herein will cover from the project start in the last quarter of 2009, through the first quarter of 2011.
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 KENNETH A PASKEN.
Thesis: Thesis (M.E.)--University of Florida, 2011.
Local: Adviser: Bloomquist, David G.

Record Information

Source Institution: UFRGP
Rights Management: Applicable rights reserved.
Classification: lcc - LD1780 2011
System ID: UFE0042947:00001

Permanent Link: http://ufdc.ufl.edu/UFE0042947/00001

Material Information

Title: Time Dependent Load Response of Flexible Pipe Subjected to Sustained Loading
Physical Description: 1 online resource (114 p.)
Language: english
Creator: PASKEN,KENNETH A
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2011

Subjects

Subjects / Keywords: 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: It is crucial to the long term sustainability of roadway drainage systems that manufacturing guidelines are stringent, but reasonable, so as to allow for maximum life efficiency of the selected products. For this reason, the Florida Department of Transportation (FDOT) has contracted the University of Florida (UF) and members of Simpson, Gumpertz, & Heger, Incorporated (SGH) to perform a series of static load tests on a variety of flexible pipe materials used for storm water runoff along Florida highways. The flexible pipe materials consist of High Density Polyethylene (HDPE), Polyvinyl Chloride (PVC), aluminum, and stainless steel. During a loading sequence, there are two pipes of the same material which are lowered into a soil box. The soil box is then backfilled with soil, sealed, and then pressurized, allowing a load to be uniformly distributed to the pipes. The purpose of this testing is to record and collect pressure data from load cells placed at precise locations throughout the soil box. The pressure data, along with deflection data recorded and collected from a displacement laser which runs along a track for the length of each of the two pipes, will provide the input for an FEM analysis to be performed. The FEM analysis is being performed by Timothy J. McGrath, Ph.D., P.E. of SGH. The FEM analysis will allow for a variety of loading situations to be simulated. The results of these analyses will allow for the FDOT to codify a baseline manufacturing guideline for each of the four different pipe materials. To be specific, each pipe is manufactured with a certain amount of pre-deflection. The FDOT is looking to minimize this number so that pipes which are subjected to a variety of loading conditions on a job site will ultimately perform as they are supposed to for their life expectancy, rather than fail prematurely. The scheduled completion date for this project is the third quarter of 2013; therefore, the information presented herein will cover from the project start in the last quarter of 2009, through the first quarter of 2011.
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 KENNETH A PASKEN.
Thesis: Thesis (M.E.)--University of Florida, 2011.
Local: Adviser: Bloomquist, David G.

Record Information

Source Institution: UFRGP
Rights Management: Applicable rights reserved.
Classification: lcc - LD1780 2011
System ID: UFE0042947:00001


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1 TIME DEPENDENT LOAD RESPONSE OF FLEXIBLE PIPE SUBJECTED TO SUSTAINED LOADING By KENNETH A. PASKEN 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 2011

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2 2011 Kenneth A. Pasken

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3 To everyone in my life who has helped me along the way, giving me purpose and the inspiration to accomplish whatever may be in my path.

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4 ACKNOWLEDGMENTS I thank my supervisory committee for their mentoring and assistance throughout my undergraduate and graduate careers at the University of Florida. I thank the members of the University of Florida Coastal Engineering Laboratory for their dedication to the project I worked on. I thank my parents and family in general, for their love and inspiration, which ultimately served as the motivation for me to pursue my m aster s degree.

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5 TABLE OF CONTENTS page ACKNOWLEDGMENTS ................................ ................................ ................................ .. 4 LIST OF FIGURES ................................ ................................ ................................ .......... 7 LIST OF ABBREVIATIONS ................................ ................................ ........................... 12 ABSTRACT ................................ ................................ ................................ ................... 13 CHAPTER 1 DESIGN ................................ ................................ ................................ .................. 15 Soil Box ................................ ................................ ................................ ................... 15 Sealing of Open Gaps ................................ ................................ ............................. 15 Differential Settlement ................................ ................................ ............................. 17 Earth Pressure Cells ................................ ................................ ............................... 18 Pipe Def lection Measurement ................................ ................................ ................. 18 Load Plates and Lift Bags ................................ ................................ ....................... 19 Pipe Pre deflection ................................ ................................ ................................ 20 Soil Sat uration ................................ ................................ ................................ ........ 20 Displacement Laser ................................ ................................ ................................ 21 2 FABRICATION ................................ ................................ ................................ ........ 51 Sealing System ................................ ................................ ................................ ....... 51 Instrumentation Room ................................ ................................ ............................. 51 Instrumentation Wiring ................................ ................................ ............................ 52 3 INSTALLATION ................................ ................................ ................................ ...... 58 Industry Visit ................................ ................................ ................................ ........... 58 Preparation fo r First Test ................................ ................................ ........................ 58 Soil Saturation ................................ ................................ ................................ ........ 60 French Drain ................................ ................................ ................................ ........... 60 String Potentiometers ................................ ................................ ............................. 61 4 IMPLEMENTATION ................................ ................................ ................................ 77 First Test ................................ ................................ ................................ ................. 77 Modification of Earth Pressure Cells ................................ ................................ ....... 78 Soil Box Disassembly ................................ ................................ ............................. 79 New Air Compressor Installed ................................ ................................ ................ 79

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6 5 DATA ANALYSIS AND REVIEW ................................ ................................ ............ 86 Nuclear Density Tests ................................ ................................ ............................. 86 Triaxial Tests ................................ ................................ ................................ .......... 86 Earth Pressure Cell Readings ................................ ................................ ................. 87 Displacement Laser Readings ................................ ................................ ................ 87 Cone Penetrometer Readings ................................ ................................ ................ 87 Calibration Test ................................ ................................ ................................ ....... 88 6 CONCLUSION ................................ ................................ ................................ ...... 110 APPENDIX : LITERATURE REVIEW ................................ ................................ ........... 112 LIST OF REFERENCES ................................ ................................ ............................. 113 BIOGRAPHICAL SKETCH ................................ ................................ .......................... 114

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7 LIST OF FIGURES Figure page 1 1 Fully assembled soil box shell. ................................ ................................ ........... 23 1 2 Soil box isometric view wi th 24 inch diameter pipes. ................................ .......... 24 1 3 Soil box plan vi ew with 24 inch diameter pipes. ................................ .................. 25 1 4 Soil box profile vi ew, section A A. ................................ ................................ ....... 26 1 5 Soil box profile vi ew, section B B. ................................ ................................ ....... 27 1 6 Soil box profile vie w, section C C. ................................ ................................ ...... 28 1 7 Soil box isometric view wi th 36 inch diameter pipes. ................................ .......... 29 1 8 Soil box plan view with 36 inch diam eter pipes. ................................ .................. 30 1 9 Soil box profile view, section D D. ................................ ................................ ...... 31 1 10 Soil box profile view, section E E. ................................ ................................ ....... 32 1 11 Soil box profile view, section F F. ................................ ................................ ....... 33 1 12 Soil box plan view with load plates and lift bags (24 inch diameter pipes). ......... 34 1 13 Soil box plan view with load plates and lift bags (36 inch diameter pipes). ......... 35 1 14 Seal concept #1, isometric view and front view. ................................ ................. 36 1 15 Seal concept #1 exploded view. ................................ ................................ ........ 37 1 16 Seal concept #2, isometric view and front view. ................................ ................. 38 1 17 Seal concept #2 exploded view. ................................ ................................ ........ 39 1 18 Soil box plan view with 36 inch diameter pipes. ................................ .................. 40 1 19 Soil box profile view with named earth pressure cel ls, section E E. ................... 41 1 20 Soil box profile view with named earth pressure cel ls, section F F. .................... 42 1 21 Porthole cover extractor/positioning device. ................................ ....................... 43 1 22 Earth pressure cell. ................................ ................................ ............................. 43 1 23 Micro Epsilon laser displacement sensor and cabling. ................................ ....... 44

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8 1 24 Load plates. ................................ ................................ ................................ ........ 44 1 25 Lift bags. ................................ ................................ ................................ ............. 45 1 26 Regulator. ................................ ................................ ................................ ........... 45 1 27 Air hoses. ................................ ................................ ................................ ........... 46 1 28 Valve stem. ................................ ................................ ................................ ......... 46 1 29 Pre deflected HDPE pipe with turnbuckles. ................................ ........................ 47 1 30 Soil profile following addition of final soil lift and completion of leveling. ............. 47 1 31 Footprint of soil box outlined with orange chal k. ................................ ................. 48 1 32 Water pressure being regulated for water to stay within the footprint. ................ 48 1 33 Filling of bucket at constant pressure. ................................ ................................ 49 1 34 Stopwatch used to record the amount of time needed to fill the bucket. ............. 49 1 35 Hand crank and reel on West end of soil box. ................................ .................... 50 1 36 The cart on which the displacement laser mounts. ................................ ............. 50 2 1 Completed wall flange for sealing system. ................................ ......................... 53 2 2 Machined porthole cover. ................................ ................................ ................... 53 2 3 Instrumentation wiring guide. ................................ ................................ .............. 54 2 4 Metal strip welded onto spirally corrugated pipes. ................................ .............. 54 2 5 Filed back corrugation on HDPE pipe. ................................ ................................ 5 5 2 6 Filed back corrugation on PVC pipe. ................................ ................................ .. 55 2 7 Completed exterior of instrumentation room. ................................ ...................... 56 2 8 Completed interior of instrumentation room. ................................ ....................... 56 2 9 Instrumentation wiring prior to refining. ................................ ............................... 57 2 10 Simplified instrumentation wiring, decreasing amount of electrical noise. .......... 57 3 1 12 inch thick layer of soil at bottom of soil box. ................................ .................. 62 3 2 HDPE pipe installed in North end of soil box. ................................ ..................... 62

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9 3 3 Sealing system between pipe end and soil b ox wall. ................................ .......... 63 3 4 Completed routing of instrumentation wiring with sealant (view from inside). ..... 63 3 5 Completed routing of instrumentation wiring (view from outside). ...................... 64 3 6 HDPE pipe being lowered into soil box. ................................ .............................. 64 3 7 Pipe/wall interface prior to sealing. ................................ ................................ ..... 65 3 8 Installed rubber membrane sealing system. ................................ ....................... 65 3 9 Dumping of soil into concrete bucket. ................................ ................................ 66 3 10 Full concrete bucket hoisted over soil box. ................................ ......................... 66 3 11 Concrete bucket emptied over soil box. ................................ .............................. 67 3 12 Placement of SS2 earth pressure cell. ................................ ............................... 67 3 13 View of SS1 (left) and SS2 (right) earth pressure cells. ................................ ...... 68 3 14 Placement of NT3 earth pressure cell. ................................ ............................... 68 3 15 Soil profile following addition of final soil lift and completion of leveling. ............. 69 3 16 Final soil level in soil box. ................................ ................................ ................... 69 3 17 Load plates in the process of installation. ................................ ........................... 70 3 18 Lift bags after placement directly over center of the load plates. ........................ 70 3 19 Air hoses routed through and down soil box East wall. ................................ ...... 71 3 20 Air hoses connected to lift bags. ................................ ................................ ......... 71 3 21 Close up of air hoses being routed through soil box East wall. .......................... 72 3 22 Air hoses connected to pressure source. ................................ ........................... 72 3 23 Partial installation of the soil box top. ................................ ................................ 73 3 24 Partial installation of the soil box top. ................................ ................................ 73 3 25 Trimmed end of South section of soil box top. ................................ .................... 74 3 26 Completed installation of soil box top. ................................ ................................ 74 3 27 Sprinkler setup inside soil box with water beginning to form puddles. ................ 75

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10 3 28 French drain release valve. ................................ ................................ ................ 75 3 29 String potentiometer attached on the East end of the soil box. .......................... 76 4 1 Soil box center section being temporarily removed. ................................ ........... 81 4 2 ........ 81 4 3 Soil excavated from above South pipe. ................................ .............................. 82 4 4 South pipe being removed from soil box. ................................ ........................... 82 4 5 North face of soil box being removed. ................................ ................................ 83 4 6 Soil removed with front end loader. ................................ ................................ .... 83 4 7 North pipe after removal from soil box. ................................ ............................... 84 4 8 Old air compressor. ................................ ................................ ............................ 84 4 9 New air compressor. ................................ ................................ ........................... 85 5 1 Location of nuclear density tests performed on 03 22 2010. .............................. 89 5 2 Location of additional nuc lear density tests. ................................ ....................... 90 5 3 drant 1 Profile. ................................ ........................... 91 5 4 nt 2 Profile. ................................ ........................... 92 5 5 3 Profile. ................................ ........................... 93 5 6 rofile. ................................ ........................... 94 5 7 ile. ................................ ........................... 95 5 8 ................................ ........................... 96 5 9 South End Quadrant 3 Profile. ................................ ........................... 97 5 10 outh End Quadrant 4 Profile. ................................ ........................... 98 5 11 Unl oading. ................................ ........ 99 5 12 End Quadrant 2 Pr ofile Unloading. ................................ ...... 100 5 13 adrant 3 Profile Unloading. ................................ ...... 101 5 14 Un loading. ................................ ...... 102

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11 5 15 rofile Unloading. ................................ ..... 103 5 16 uadrant 2 Pro file Unloading. ................................ ..... 104 5 17 U nloading. ................................ ..... 105 5 18 Profile Unloading. ................................ ..... 106 5 19 Quadrant orientations, viewing from East end to West end. ............................. 107 5 20 Cone penetrometer testing apparatus. ................................ ............................. 107 5 21 Earth pressure cell layout for calibration test, with naming convent ion. ............ 108 5 22 Name convention for earth pressure cells beneath plates. ............................... 109

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12 LIST OF ABBREVIATION S FDOT Florida Department of Transportation FEM Analysis Finite Element Analysis HDPE High Density Polyethylene PVC Polyvinyl Chloride SMO State Materials Office UF University of Florida

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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 TIME DEPENDENT LOAD RESPONSE OF FLEXIBLE PIPE SUBJE CTED TO SUSTAINED LOADING By Kenneth A. Pasken May 2011 Chair: David Bloomquist Major: Civil Engineering It is crucial to the long term sustainability of roadway drainage systems that manufacturing guidelines are stringent, but reasonable, so as to allow for maximum life efficiency of the selected products. For this reason, the Florida Dep artment of Transportation (FDOT) has contracted the University of Florida (UF) and members of Simpson Gumpertz & Heger Incorporated (SGH) to perform a series of static load tests on a variety of flexible pipe materials used for storm water runoff along Florida highways. The flexible pipe materials consist of High Density Polyethy lene ( HDPE ), Polyvinyl Chloride ( PVC ) aluminum, and stainless s teel. During a loading sequence, there are two pipes of the same material which are lowered into a soil box. The soil box is then backfilled with soil sealed, and then pressurized, allowing a load to be uniformly distributed to the pipes. The purpose of this testing is to reco rd and collect pressure data from load cells placed at precise locations thr oughout the soil box The pressure data, along with deflection data recorded and collected from a displacement laser which runs along a track for the length of each of the two pipe s, will provide the input for an FEM analysis to

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14 be performed The FEM analysis is being performed by Timothy J. McGrath, Ph.D., P.E. of SGH The FEM analysis will allow for a variety of loading situations to be simulated. The results of these analyses wil l allow for the FDOT to codify a baseline manufacturing guideline for each of the four different pipe materials. To be specific, each pipe is manufactured with a certain amount of pre deflection. The FDOT is looking to minimize this number so that pipes wh ich are subjected to a variety of loading conditions on a job site will ultimately perform as they are supposed to for their life expectancy, rather than fail prematurely. The scheduled completion date for this project is the third quarter of 2013; therefo re, the information presented herein will cover from the project start in the last quarter of 2009, through the first quarter of 2011.

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15 CHAPTER 1 DESIGN Soil Box T he soil box being used for the testing procedure s is made of steel and is assembled i n a number of different pieces. There are three bottom sections, three top sections, and a total of eight side sections, one for each of the North and S outh faces and three for each of the East and West faces. When f ully assembled, the soil box measures 20 feet long by 10 feet wide by 8 feet deep. The fully assembled soil box can be seen in Figure 1 1 at the end of this chapter. In regards to the specific design aspects which follow there were many considerations to take into account, as specified in previous studies (Brachman et al. 2000). Sealing of Open Gaps One of the most important aspects of the testing procedure is to keep the system completely clo sed. At the project onset, this particular item proved to be quite difficult to solve. Each of the three side sections for the East and West faces has an open porthole. More detail of the soil box and the loading configuration can be seen in Figures 1 2 th rough 1 13 and Figures 1 18 through 1 20 The testing procedure calls for only two pipes of the same material to be tested at any one time. Therefore, the portholes on the center side sections are covered using the apparatus shown in Figure 1 21 For the i nterface between the pipe ends and the soil box side walls, there was a lot of discussion about an appropriate sealing system. Among the considerations in the selection process were the following: the side walls of the soil box are not completely vertical; the solution must provide for adequate free movement on both ends of the pipe,

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16 so that the pipe ends do not drag on the side of the soil box; and that all the pipes have either spiral or circular corrugations, making it difficult for any elastic type mate rial to completely wrap around the outside pipe edge. The first concept, which is detailed in Figures 1 14 and 1 15 involved using inflatable tubes around the pipe perimeter. The idea was to wrap a two inch wide PVC strip around the outside of the pipe end. Then, the tubes would be laid on the PVC strip, deflated. A secondary two inch wide PVC strip, with a larger diameter than the first, would then serve as an outer casing for the tubes so that the inflated size would be limited. This would be performed on both ends of the pipe, and then the assembly would be lowered into the tank, after which time the tubes would be inflated. Ultimately, this option brought up concerns of cost feasibility because of the custom nature of most of the parts that would need to be used. Also, the pressure that the tubes would need to be inflated to in order to provide adequate seal would have been so much that the pipe would effectively be fixed at both ends. This would have interfered with the dynamics of the test, not allow ing the pipe to move freely along its entire length. Details for the second concept can be found in Figures 1 16 and 1 17 This concept makes use of a wall flange bolted onto the wall of the soil box. A rubber membrane is then wrapped around the protruding part of the flange. The other end of the membrane is then wrapped around the pipe end. Spirally corrugated pipes have the membrane wrapped around a metal strip that was machined to the inside pipe perimeter, extending slightly beyond the pipe end. For the pipes with circular corrugations, the rubber membrane wraps around a portion of the pipe where the

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17 corrugation has been filed back about two inches. Pictures for the modified pipe ends for both types of corrugations are found in Figures 2 4 through 2 6 A s long as the rubber membra ne is between the range of soft t o medium soft, this option will allow the pipe to move freely along its entire length. Moreover, the rubber membrane will be fabricated to be slightly wider than needed. Therefore, when the load i s applied from above and movement of the pipe begins, there will not automatically be concept was also selected because of its cost effectiveness, with only the rubber membrane ne eding to be purchased from an outside vendor. The third concept was only briefly discussed, but nonetheless was an option to consider. The idea was to create a square Styrofoam block with a hole cut through the center, the hole being the size of the diamet er of the pipe. The Styrofoam would then be pressed on to the pipe end on both sides, and the assembly would then be lowered into the soil box. As with the first concept, this was eventually ruled out because the Styrofoam would have to be so stiff, that i t too would make the pipe ends fixed to the soil box walls. Differential Settlement Another task of importance was the discussion and selection of an appropriate method for avoiding differential settlement of the load plates. This particular issue with the project has proved somewhat difficult to find a s olution to. It was ultimately decided that the load plate configuration chosen would not allow for differential movements. The chosen layout can be seen in Figures 1 12 and 1 13.

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18 Earth Pressure Cells In regard to the selection of locations for earth pressure cells within the soil box, only 18 earth pressure cells are necessary for the soil box being tested with two pipes. The earth pressure cells that are being used can be seen in Figure 1 22 Figures 1 2 through 1 11 provide numerous views and details of the locations for the earth pressure cells. Figures 1 2 through 1 6 detail the locations for the tests with the 24 inch diameter pipes, while Figures 1 7 through 1 11 detail the locations for the tests with the 36 inch diameter pipes. This setup represents the best layout of earth pressure cells to be able to obtain the most variety of data. The location of all the earth pressure cells and their respective names can be found in Figures 1 18 through 1 20 Pipe Deflection Measurement Whereas it was initially thought that a laser sy stem would be cost prohibitive, an industry contact offered to provide the u niversity with a track mounted laser which had a 360 degree spinning mirror, as well as a camera. The pieces of equipment needed, along with the software and other data logging equipment, was going to be provided free of charge. This initial idea was strongly considered based on the review of a study performed at the University of Texas at Arlington using the CUES, Inc. Laser Profiler (Abolmaali 2008). However, t he industry contact informed the u niversity of the unavailability of the equipment that had been promised. This was an unfortunate setback; another study performed at the University of Texas at Arlington provided added verification as to the accuracy of the CUES, Inc. system (Motahari et al. 2008). A different solution however, was quickly discovered. On anoth er FDOT/UF project, a laser had been used f or the purposes of displacement measurement. That project has since been brought to a close, and the

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19 laser was unused over at the FDOT State Materials Office (SMO) Daniel Pitocchi, the Soils and Foundation Lab Ma nager over at the SMO, was kind enough to provide the laser. A detailed discussion of the mounting system will take place towards the end of this chapter The laser being used, shown in Figure 1 23 has a start of m easuring range equal to 200 mm, or 7.9 in ches, and an end of measuring range of 950 mm, or 37.4 inches. This means that the target can be no closer than 7.9 inches, and no farther away than 37.4 inches. The mounting system developed takes into account these maximum and minimum limits. The resolution is 50 micrometers, or about 0.002 inches. This is more than accurate for the tests be ing performed. Load Plates and Lift Bags The load plate and lift bag configuration had to be designed to achieve the most uniform pressure distribution and to avoid eccentric loading. A number of loading conditions and methods of load transfer were analyzed for this particular aspect of the project (Smith et al. 2005). Initially, the uniform loading of the soil box was going to take pl ace with the use of eight, five foot square load plates. Each load plate would have a 42 inch square lift bag on top of it. However, this setup did not provide for optimal testing conditions because the plates were located in such a manner that the joint between two plates was over the centerline of the pipe. This issue would cause extreme tilting of the plates once the loading began. Instead, the decision was made to use six of the five foot square plates toward s the inside of the box, and four smaller plates towards the outside. Four new lift bags with smaller dimensions had to be ordered to accommodate this new design. Details of this layout are found in Figures 1 12 and 1 13 With this setup, the load plates are either

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20 directly over the fill, or directly over the centerline of t he pipe. The tilting set tlement is therefore eliminated. The change in number and layout of load plates and lift bags was made prior to the ordering of the plates, so no additional plates were necessary. However, the layout design modification did come aft er the eight large lift bags were ordered and deliver ed. F our smaller lift bags had to be ordered. The loads plates a nd lift bags can be seen in Figures 1 24 and 1 25 The lift bags were delivered along with all the necessary connectivity equipment, includ ing regulators, valves, a nd hoses. These are seen in Figures 1 26 through 1 28 Pipe Pre deflection This aspect of the testing aims to further simulate field conditions during pipe installation. This pre deflection of the pipes was made possible with the u se of manual turnbuckles, shown in Figure 1 29 Four percent pre deflection, or 1.44 inches, was achieve d for the 36 inch diameter HDPE pipes Because this decision was made after one of the pipes had alr eady been installed in the s oil b ox, the pipe was removed, pre deflected, and then reinstalled. In order to maintain the deflec ted shape, the turnbuckles remain in place until the test s are begun. T he lift bags will exert enough pressure on the pipes so that the turnbuckles are released, allowing for thei r safe removal through the portholes. Soil Saturation One of the important parts of the testing procedure i s to fully saturate the soil. The soil added to the soil box has a moisture content of around three percent. Using soil phase diagram relationships a nd an average of the actual dry unit weights obtained from the triaxial test results, it was calculated that approximately 3,200 gallons of water

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21 would be needed to fully saturate the soil. This number was base d on two assumptions: that the s oil b ox was fi lled completely with soil and that the soil could be fully saturated. As can be seen in Figure 1 30 there are about six inches of freeboard near the top of the box. Also, it would be near impossible to fully saturate the soil, unless all the soil was main tained in an airtight configuration and flooded. That was not a likely consideration. To be able to accurately record exactly how muc h water was being added to the soil b ox, a trial was performed outside of the UF Coastal Engineering Lab oratory The footpr int of the soil b ox was measured out and outlined with orange chalk. A lawn sprinkler was then connected to the water supply, and the pressure regulated until the water fell within the chalk boundary. This pressure was then held constant while the sprinkle r was held over a bucket of known volume. The time required to fill the bucket to three gallons was one minute and 55 seconds. The above steps can be seen in Figures 1 31 through 1 34. It would take appr oximately 34 hours to fill the soil b ox with 3200 gallons, maintaining the low pressure necessary to stay within the footprint The lawn sprinkler represents the best way to uniformly distribute the water over such a long period of time. Displacement Laser The laser mounting system allows for extrem ely precise deflection measurements. The process is accomplished by means of a beam that is fixed to the soil b ox walls at each end of the pipes. The laser is attached to a cart which moves along the length of the beam with the use of a hand crank, a ttache d on the West end of the soil b ox. Attached to the cart is a strin g which is spooled inside of a string potentiometer. As the

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22 cart moves along the length of the pipe, both displacement measurements from the laser and horizontal distance along the pipe from the string potentiometer are output to a data acquisition program. The hardware can be seen in Figures 1 35 and 1 36 It was ultimately decided that a string potentiometer would be best to measure the horizontal translation of the laser as the laser moves along the track system it is mounted on. T he string potentiometer output s to the same piece of equipment as the other instrumentation, simplifying the data acquisition process.

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23 Figure 1 1. Fully assembled soil box shell. Photo credit: K. Pasken.

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24 Figure 1 2 Soil box isometric view with 24 inch diameter pipes. [Reprinted with permission from Bloomquist, D. G. 2010 BDK75 977 21 Progress Report 2 (Page 19 ). University of Florida, Gainesville, Florida.]

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25 Figure 1 3 Soil box plan view with 24 inch diameter pipes. [Reprinted with permission from Bloomquist, D. G. 2010. BDK75 977 21 Progress Report 2 (Page 20 ). University of Florida, Gainesville, Florida.]

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26 Figure 1 4 Soil box profile view, section A A. [Reprinted with permission from Bloomquist, D. G. 2010. BDK75 977 21 Progress Report 2 (Page 2 1 ). University of Florida, Gainesville, Florida.]

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27 Figure 1 5 Soil box profile view, section B B. [Reprinted with permission from Bloomquist, D. G. 2010. BDK75 977 21 Progress Report 2 (Page 22). University of Florida, Gainesville, Florida.]

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28 Figure 1 6 Soil box profile view, section C C [Reprinted with permission from Bloomquist, D. G. 2010. BDK75 977 21 Progress Report 2 (Page 2 3 ). University of Florida, Gainesville, Florida.]

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29 Figure 1 7 Soil box isometric view with 36 inch diameter pipes. [Reprinted with permission from Bloomquist, D. G. 2010. BDK75 977 21 Progress Report 2 (Page 2 4 ). University of Florida, Gainesville, Florida.]

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30 Figure 1 8 Soil box plan view with 36 inch diamete r pipes. [Reprinted with permission from Bloomquist, D. G. 2010. BDK75 9 77 21 Progress Report 2 (Page 25 ). University of Florida, Gainesville, Florida.]

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31 Figure 1 9 Soil box profile view, section D D [Reprinted with permission from Bloomquist, D. G. 20 10. BDK75 9 77 21 Progress Report 2 (Page 26 ). University of Florida, Gainesville, Florida.]

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32 Figure 1 10. Soil box profile view, section E E [Reprinted with permission from Bloomquist, D. G. 2010. BDK75 977 21 Progress Report 2 (Page 2 7 ). University of Florida, Gainesville, Florida.]

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33 Figure 1 11. Soil box profile view, section F F [Reprinted with permission from Bloomquist, D. G. 2010. BDK75 977 21 Progress Report 2 (Page 2 8 ). University of Florida, Gainesville, Florida.]

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34 Figure 1 12. Soil box plan view with load plates and lift bags (24 inch diameter pipes). [Reprinted with permission from Bloomquist, D. G. 2010. BDK75 977 21 Progress Report 2 (Page 29 ). University of Florida, Gainesville, Florida.]

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35 Figure 1 13. Soil box plan view with load plates and lift bags (36 inch diameter pipes). [Reprinted with permission from Bloomquist, D. G. 2010. BDK75 977 21 Progress Report 2 (Page 30). University of Florida, Gainesville, Florida.]

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36 Figure 1 14. Seal concept #1, isometric view and front view. [ Reprinted with permission from Bloomquist, D. G. 2010. BDK75 977 21 Progress Report 2 (Page 31 ). University of Florida, Gainesville, Florida.]

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37 Figure 1 15 Seal concept #1, exploded view. [Reprinted with permission from Bloomquist, D. G. 2010. BDK75 9 77 21 Progress Report 2 (Page 32 ). University of Florida, Gainesville, Florida.]

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38 Figure 1 16. Seal concept #2 isometric view and front view. [Reprinted with permission from Bloomquist, D. G. 2010. BDK75 977 21 Progress Report 2 (Page 33 ). University of F lorida, Gainesville, Florida.]

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39 Figure 1 17. Se al concept #2 exploded view. [Reprinted with permission from Bloomquist, D. G. 2010. BDK75 9 77 21 Progress Report 2 (Page 34 ). University of Florida, Gainesville, Florida.]

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40 Figure 1 18 Soil box plan view with 36 inch diameter pipes. [Reprinted with permission from Bloomquist, D. G. 2010 BDK75 977 21 Progress Report 3 (Page 2 7 ). University of Florida, Gainesville, Florida.]

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41 Figure 1 19 Soil box profile view with named earth pressure cells, section E E. [Reprinted with permission from Bloomquist, D. G. 2010. BDK75 977 21 Progress Report 3 (Page 28 ). University of Florida, Gainesville, Florida.]

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42 Figure 1 20 Soil box profile view with named earth pressure cells, section F F. [Reprinted with permission from Bloomquist, D. G. 2010. BDK75 977 21 Progress Report 3 (Page 29). University of Florida, Gainesville, Florida.]

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43 Figure 1 21 Porthole cover extractor/positioning device. Photo credit: K. Pasken. Figure 1 22 Earth pressure c ell Photo credit: K. Pasken.

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44 Figure 1 2 3 Micro Epsilon laser displacement s ensor and cabling. Photo credit: K. Pasken. Figure 1 2 4 Load plates. Photo credit: K. Pasken.

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45 Figure 1 2 5 Lift bags. Photo credit: K. Pasken. Figure 1 2 6 Regulator. Photo credit: K. Pasken.

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46 Figure 1 2 7 Air hoses. Photo credit: K. Pasken. Figure 1 28 Valve stem. Photo credit: K. Pasken.

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47 Figure 1 29 Pre deflected HDPE pipe with turnbuckles. Photo credit: K. Pasken. Figure 1 3 0 Soil profile following addition of final soil lift and completion of leveling. Photo credit: K. Pasken.

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48 Figure 1 3 1 Footprint of s oil b ox outlined with orange chalk. Photo credit: K. Pasken. Figure 1 3 2 Wat er pressure being regulated for water to stay within the footprint. Photo credit: K. Pasken.

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49 Figure 1 3 3 Filling of bucket at constant pressure. Photo credit: K. Pasken. Figure 1 3 4 Stopwatch used to record the amount of time needed to fill the bucket. Photo credit: K. Pasken.

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50 Figure 1 35. Hand crank and reel on West end of soil b ox. Photo credit: K. Pasken. Figure 1 36. The cart on which the displacement laser mounts. Photo credit: K. Pasken.

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51 CHAPTER 2 FABRICATION Sealing System Fi gure 2 1 demonstrates what the completed wall flange looks like when bolted onto the soil box side wall. Due to the large amount of instrumentation equipment being used for this project, careful attention was taken to ensure proper organization of all wiri ng. All instrumentation wiring will exit through the center porthole on the East side of the soil box. This porthole cover was machined, as shown in Figure 2 2 to allow for proper exit of all instrumentation wiring. Figure 2 3 shows what the instrumentation wiring will be guided through so there is no chance of wires being cut or improperly holes that were machined on the soil box porthole cover. In order for the pipes to properly interface with the sealing sys tem discussed in Chapter 1 the spirally corrugated pipes needed to have a strip of metal welded to the inside perimeter. This slight modification can be seen below in Figure 2 4 for the a luminum pipes. The same modification was perform ed on the stainless s teel pipes. For the pipes with circular corrugations, no additional meta l strip was added. Instead, the corrugation was filed back. See Figures 2 5 and 2 6 for the HDPE and PVC pipes. Instrumentation Room The instrumentation room was r equired for protection of all da ta acquisition hardware and the various pieces of instrumentation. There is a window on the East face of the room to allow for air ventilation. It also provides ease of communication between the person operating the laser an d the person sitting at the computer at which the data

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52 is collected. Exterior and interior views of the completed instrumentation room can be seen in Figures 2 7 and 2 8 Instrumentation Wiring One of the major concerns in the final phases before testing w as electrical noise present in the instrumentation signals for the displacement laser and string potentiometers. Figure 2 9 represents the initial condition which had a great deal of clutter. Absent from that figure is the power source for the displacement laser. Figure 2 10 represents the current condition for the instrumentation wiring. The two circuit boards have been replaced, and all connections have been soldered and heat shrunk. Performing this upgrade to the instrumentation wiring has proved to be v ery successful in eliminating most, if not all, of the electrical noise.

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53 Figure 2 1. Completed wall flange for sealing system. Photo credit: K. Pasken. Figure 2 2. Machined porthole cover. Photo credit: K. Pasken.

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54 Figure 2 3. Instrumentation wiring guide. Photo credit: K. Pasken. Figure 2 4. Metal strip welded onto spirally corrugated pipes. Photo credit: K. Pasken.

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55 Figure 2 5. Filed back corrugation on HDPE pipe. Photo credit: K. Pasken. Figure 2 6. Filed back corrugation on PVC pipe Photo credit: K. Pasken.

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56 Figure 2 7. Completed exterior of instrumentation room. Photo credit: K. Pasken. Figure 2 8 Completed interior of instrumentation room. Photo credit: K. Pasken.

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57 Figure 2 9. Instrumentation wiring prior to refining. Photo credit: K. Pasken. Figure 2 10. Simplified instrumentation wiring, decreasing amount of electrical noise. Photo credit: K. Pasken.

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58 CHAPTER 3 INSTALLATION Industry Visit The soil b ox was partiall y set up for the purposes of an industry visit which took place on Tuesday, March 16, 2010. This partial set up included the 12 inch t h ick layer of compacted soil at the bott om of the soil b ox, as well as the installation of an HDPE pipe in the North end of the box. As can be seen in Fi gures 3 1 through 3 3 the 12 inch thick layer was compacted uniformly and the rubber membrane sealing system was installed over the interface between the pipe end and the soil box wall. Preparation for First Test After the industry v isit, the soil box con tinued to be prepared for the first test. This particular task was accomplished in a number of stages. The bottom 12 inch thick layer of compacted fill was already in place. The next step was to properly route all the instrumentation wiring thro ugh the cen ter porthole. See Figures 3 4 and 3 5 for the completed instrumentation wiring. The 36 inch diameter HDPE pipes were used for the first test. Figure 3 6 shows how the pipes are lowered into the soil b ox. Both pipes were pre deflected to four percent along the ten foot length, or about 1.44 inches. After the pipes were lowered, the rubber membrane sealing system was install ed over the four open joints. V iews of the pipe/wall interface prior to and immediately after the installation of the sealing system can be seen in Figures 3 7 and 3 8, respectively Immediately following the installation of both pipes, soil began to be loaded into the box. This was done in three separate lifts and was accomplished with the use of a front end loader dumping soil into a con crete bucket. The concrete bucket was then

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59 hoisted over the soil box, and its contents emptied. This process c an be seen in Figures 3 9 through 3 11. The next step in the process, which took place in conjunction with filling, was to properly place the eart h pressure cells. The cells needed to be located according to the specifications outlined in Chapter 1, as can be seen in Figures 3 12 through 3 14. Finally, after the last lift of soil was added to the soil box, the soil was leveled uniformly. See Figure 3 15 Once again, careful attention was paid to ensure that the soil was not compacted any more than required. This was verified by nuclear d ensity tests, which are discussed in Chapter 5. A final four to six inches of soil were added to close the eventual gap between the bottom of the soil b ox top and the lift bags that would be placed on top of the load plates. The final soil lev el can be seen in Figure 3 16 The next step was to install the load plates on top of the soil. The load plates were lifted indi vidually and set in their appropriate locations. As per the specifications six five foot by five foot and four two and a half foot by five foot load plates were installed. This step can be seen in Figure 3 17. After the load plates were successfully insta lled, the lift bags needed to be set in place. They were hoisted into place in the same manner as the load plates. See Figure 3 18 The smaller lift bags seen towards the en d of the long dimension of the soil b ox are so sized to account for the smaller loa d plates. This is to avoid eccentric loading of the soil. The next step in the process was to connect all the necessary equipment for pressurizing the lift bags, as seen in Figures 3 19 through 3 22 The air hoses were

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60 connected to the lift bags, route d th rough drilled holes in the soil b ox East wall and down the wall into a flange, connecting all the air hoses to one air supply. Following the installation of the lift bags and air pr essurizing equipment, the soil b ox top was ready to be installed. The top i s comprised of three sections, the outer two being wider than the middle section. This particular task proved especially difficult due to the need to line up all the holes on the top with the vertical walls. The objects lying on top of the lift bags, seen in Figures 3 23 and 3 24 were used to temporarily hold the sections in place while the holes were lined up. These two figures also show the South section after placement. Due to complications with correctly lining up all three sections, an end of the Sout h section needed to be slightly trimmed. The alteration can be seen in Figure 3 25. Once this was performed, the top could be properly put in place and fastened with all the necessary hardware, seen in Figure 3 26 This was the last step in preparing the s oil b ox itself for the first test. Soil Saturation Because full saturation could n ot be attained and because the soil b ox was not completely filled, water was added to the soil b ox for about half of the 34 hours, or about 18 hours. This was done over the c ourse of three days. Figure 3 27 shows the sprinkler setup in th e soil b ox towards the end of the watering process. In the middle of the photo, water can be seen beginning to form puddles. French Drain This particular task was needed for drainage purposes once the soil was saturated. The French drain is located along t he South end of the soil b ox. A porous

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61 membrane allows only water to penetrate into the drain. This prevents soil from clogging the drain. The drainage spout can be seen in Figure 3 28 String Potentiometers String potentiometers were ordered and subsequently installed on the laser mounting system. Each pipe being tested has the setup shown in Figure 3 29 This makes the data acquisition process much quicker when compared to having to move the entire rig from one pipe to the other.

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62 Figure 3 1. 12 inch thick layer of soil at bottom of soil box. Photo credit: K. Pasken. Figure 3 2. HDPE pipe installed in North end of soil b ox. Photo credit: K. Pasken.

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63 Figure 3 3 Seali ng system between pipe end and soil b ox wall. Photo credit: K. Pasken. Figure 3 4 Completed routing of instrumentation wiring with sealant (view from inside). Photo credit: K. Pasken.

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64 Figure 3 5 Completed routing of instrumentation wiring (view from outside). Photo credit: K. Pasken. Figure 3 6 HDPE pipe being lowered into soil box. Photo credit: K. Pasken.

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65 Figure 3 7 Pipe/wall interface prior to sealing. Photo credit: K. Pasken. Figure 3 8 Installed rubber membrane sealing system. Photo credit: K. Pasken.

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66 Figure 3 9 Dumping of soil into concrete bucket. Photo credit: K. Pasken. Figure 3 10 Full concrete bucket hoisted over soil box. Photo credit: K. Pasken.

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67 Figure 3 11 Concrete bucket emptied over soil box. Photo credit: K. Pasken. Figure 3 12 Placement of SS2 earth pressure cell. Photo credit: K. Pasken.

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68 Figure 3 13 View of SS1 (left) and SS2 (right) earth pressure cells. Photo credit: K. Pasken. Figure 3 14 Placement of NT3 earth pressure cell. Photo credit: K. Pasken.

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69 Figure 3 15 Soil profile following addition of final soil lift and completion of leveling. Photo credit: K. Pasken. Figure 3 16 Final soil level in soil b ox. Photo credit: K. Pasken.

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70 Figure 3 17 Load plates in the process of installation. Photo credit: K. Pasken. Figure 3 18 Lift bags after placement directly over center of the load plates. Photo credit: K. Pasken.

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71 Figure 3 19 Air hoses routed through and down soil b ox East wall. Photo credit: K. Pasken. Figure 3 20 Air hoses connected to lift bags. Photo credit: K. Pasken.

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72 Figure 3 21 Close up of air hoses being routed through soil b ox East wall. Photo credit: K. Pasken. Figure 3 22 Air hoses connected to pressure source. Photo credit: K. Pasken.

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73 Figure 3 23 Partial installation of the soil b ox top. Photo credit: K. Pasken. Figure 3 24 Partial installation of the soil b ox top. Photo credit: K. Pasken.

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74 Figure 3 25 T rimmed end of South section of soil b ox top. Photo credit: K. Pasken. Figure 3 26 Completed installation of soil b ox top. Photo credit: K. Pasken.

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75 Figure 3 27 Sprinkler setup inside soil b ox with water beginning to form puddles. Photo credit: K. Pasken. Figure 3 28 French drain release valve. Photo credit: K. Paske n.

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76 Fig ure 3 29 String potentiometer attached on the East end of the soil box. Photo credit: K. Pasken.

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77 CHAPTER 4 IMPLEMENTATION First Test The first test began on Monday, August 23, 2010 with two pre deflected 36 inch HDPE pipes inside the soil b ox. Zero readings were taken on all of the earth pressure cells and with the displacement laser on Thursday, August 19, 2010. On Monday the 23rd, the system began to be pressurized, starting off at 2 psi and increasing by 2 psi increments until 8.33 psi was reached. This specific pressure correlated to a surcharge load of 10 feet. The increments were then raised to 3.33 psi until a pressure of 16.67 psi was reached, simulating a surcharge depth of 20 feet. For the range of 20 feet to 50 feet of surcharge, or 16.67 psi to 41.67 psi, respectively, the pressure increment was increas ed to 5 psi. Based on the earth pressure cell readings and displacement laser readings, some discussion began about what the actual pressures were that were being applied. In reali ty, when the lift bags are inflated, the footprint they have on the load plates is diminished because they expand in the vertical direction. It is because of this reduced contact area that the pressures being recorded throughout the soil were much less tha n what was being measured as the applied pressure from the air source. Large quantities of measurements were taken to r ecord pressures throughout the soil b ox and deflections of the pipes. Ultimately, a maximum pressure of 66.67 psi was applied to the lift bags. This was the maximum available air pressure capacity which could be provided by the air compressor at the UF Coastal Engineering Laboratory. The initial loading sequence was followed by an unloading sequence, and then a more rapid reloading sequence The latter is discussed in greater detail below Part of the reason

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78 for the extensive amount of time required for the first test was the need to unload the box at nearly the same rate at which it was loaded. With future tests, there will need to be less time in between pressure increases to cut down on the overall required time for each test. Modification of Earth Pressure Cells After the soil box was unloaded, t wo additional earth pressure cells were installed directly beneath the center load plates and the soil b ox was re pressurized. The purpose of this particular task was to be able to more accura tely assess the pressures being applied to the soil b ox. The issue has to do with the contact area between the lift bags and the load plates. Because of this, t he pressure being applied to the lift bags is an overstatement of the pressures being applied to the soil beneath the load plates. Since there was the unique advantage of having the entire setup assembled with all instrumentation still in place, the deci sion was made to install two pressure cells, one beneath the center of each of the two center load plates. The center section of the soil b ox lid was simply removed, along with the lift bags and load plates in the center section. The two new cells were ins talled, with cables being routed out of the soil b ox and into the data logging equipment. The load plates, lift bags, and center sec tion of the soil b ox lid were then reinstalled. Aspects of the procedure can be seen in Figure s 4 1 and 4 2. A rapid reloadi ng sequence ensued to record what the pressures were directly beneath the load plates. The time in between raising the pressure was not as much of a concern because the only interest was the pressure directly beneath the load plates, not the pressure in th e soil. Therefore, the stress strain properties of the soil did not affect the readings of interest. The reloading sequence was accomplished in one day. Even

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79 with this extra task, there was still speculation about whether or not the numbers obtained could be relied upon. It was ultima tely decided that a soil b ox calibration test should be performed. This is discussed in more detail in Chapter 5 Soil Box Disassembly The soil b ox was disassembled after successful conclusion of the first test. This project ta sk was accomplished in a number of steps, pay ing very close attention to the layout of the earth pressure cells within the soil. It was very important to remove the soil in a manner consistent with not heavily disturbing the earth pressure cells, so as to avoid damaging the cells. The South pipe was the first to be removed, with the soil directly above the pipe being excavated out along with the pressure cells in the vicinity. This aspect of disassembly can be seen in Figure 4 3 The South pi pe was then hoi sted out of the soil b ox, as seen in Figure 4 4 The next step was to remove the North pipe. The approach for this particular step involved removing the North face of the soil box, allowing the s oil to be removed from the box simply by gravity. The remaini ng soil was then removed with a front end loader. Once enough soil had been removed, the North pipe was carefully removed, again with the use of the front end loader. The remaining soil and earth pressure cells were finally removed, concluding the disassem bly of the soil box. See Figures 4 5 through 4 7. New Air Compressor Installed A new, higher capacity air compressor was installed at th e U F Coastal Engineering Laboratory to be able to more adequately meet the needs of this project. When the issue arose t hat the pressures being applied to the load plates were less than what was being applied to the lift bags, there was some concern about the air compressor being used on the project. Assuming the pressures in the lift bags and

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80 those being applied to the loa d plates were equal, the air compressor being used reached its maximum output capacity when feet. Seeing as how this was not the case, an air compressor was needed which could produce much higher pressures. Figures 4 8 and 4 9 show the old air compressor and the new air compressor, respectively.

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81 Figure 4 1 Soil b ox center section being temporarily removed. Photo credit: K. Pasken. Figure 4 2 ing added in the center of the soil b ox. Photo credit: K. Pasken.

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82 Figure 4 3 Soil excavated from above South pipe. Photo credit: K. Pasken. Figure 4 4 South pipe being removed from soil b ox. Photo credit: K. Pasken.

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83 Figure 4 5 North face of soil b ox being removed. Photo cred it: K. Pasken. Figure 4 6 Soil removed with front end loader. Photo credit: K. Pasken.

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84 Figure 4 7 North pipe after removal from soil b ox. Photo credit: K. Pasken. Figure 4 8 Old air compressor. Photo credit: K. Pasken.

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85 Figure 4 9 New air compressor. Photo credit: K. Pasken.

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86 CHAPTER 5 DATA ANALYSIS AND RE VIEW Nuclear Density Tests Nuclear densit y tests were performed by FDOT t echnicians from the SMO on the soil being added to the soil b ox. These tests were done on four separate occasions: March 22, April 28, April 29, and May 3, 2010. Each of these dates corresponds to a lift of s oil that had been added to the soil b ox. The test done on March 22 assessed the compaction in the first lift of soil which was 1 foot thick. Su bsequently, two lifts each with a thickness of two feet were added to the soil b ox. The tests performed on April 28 and April 29 checked the respective compaction levels. Finally, two and a half feet of soil was added. The compaction of this final lift was assessed on May 3. The location of all the nuclear density tests that were performed can be found in Figures 5 1 and 5 2. From the nuclear density test data, the average moisture content of the soil in the soil b ox was calculate d as three percent. Triaxial Tests Existing triaxial test results were provided by Mr. Daniel Pitocchi, the Soils and Fo undation Lab Manager at the SMO. The existing data corresponded to the soil being tested at 100 percent standard proctor density. Each s ample was tested at 7, 14, and 21 psi confining pressures. exis ting in the s oil b ox, new triaxial tests were performed. Specifically, new testing parameters included lowering the confining pressure to a level that could be maintained reliably, and testing at lower standard densities. The new tests were run on soil samples at 80, 85, and 90 percent standard proctor densities.

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87 Earth Pressure Cell Readings Earth pressure cell readings were taken on a nu mber of dates. The data is being provided to Mr. Bryan P. Strohman of SGH in Micros oft Excel format This is for th e purposes of the FEM Analysis to be performed based on the pressure readings. Displacement Laser Readings Displacement laser readings were l ikewise taken on a number of dates. As with the earth pressure cell data, the displacement laser data is being provided to Mr. Bryan P. Strohman of SGH. Previous studies performed with similar designs and loading conditions are being taken into account whe n doing the data analysis and review for this project (Brachman et al. 1996). Figures 5 3 through 5 18 show the deflection measurement of each pipe q uadrant plotted against the length dimension of the pipes for the pressures bei ng applied. There are notice able changes in the plots as the pressure is increased. However, the deflections from the zero readings are not actually that large. This fact is what first sparked doubts regarding the actual pressure being applied in the soil. The graphic in Figure 5 19 shows the quadrant orientations when looking from the East end of the pipe to the West end. Therefore, Quadrant 1 points North, Quadrant 2 points to the top of the pipe, Quadrant 3 points South, and Quadrant 4 points to the bottom of the pipe. Cone Penetro meter Readings Cone penetrometer spot readings were ta ken after the lid of the soil b ox was removed. This task was performed simply to see what the state of the soil was after successful completion of a loading and unloading sequence. The test is a measure of the in kilograms per square centimeter, which is approximately equal to one ton per square

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88 foot (tsf). A number of readings were taken t hroughout the footprint of the so il b ox, averaging about 20 tsf. The cone penetrometer can be seen in Figure 5 20. Calibration Test Towards the conclusion of the first test, it became apparent that a calibration test might be needed to bett er assess the pressures in the soil b ox. Although this requires the need for extra time, it was ultimately decided that this was a vital part of the experiment to validate the results collected thus far and those to be collected in the next six tests. A layout of the earth pressure cells for the calibrat ion test can be seen in Figures 5 21 and 5 22 Vertical strains will be obtained at the specified locations with the use of string potentiometers mounted to stationary l ocations on the outside of the soil b ox. Although this number of cells may seem excessi ve, this layout was chosen because the equipment and data logging capacity was available. This redundancy also serves as a backup plan in case any of the cells f ail. No pipes are installed in the soil b ox for the calibration test.

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89 Figure 5 1 Lo cation of nuclear density tests performed on 03 22 2010. [Reprinted with permission from Bloomquist, D. G. 2010. BDK75 977 21 Progress Report 3 (P age 25 ). University of Florida, Gainesville, Florida.]

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90 Figure 5 2 Location of additional nuclear density t ests. [Reprinted with permission from Bloomquist, D. G. 2010. BDK 75 977 21 Progress Report 3 (Page 26 ). University of Florida, Gainesville, Florida.]

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91 Figure 5 3 [Reprinted with permis sion from Bloomquist, D. G. 2011 BDK75 977 21 Progress Report 5 (Page 20). University of Florida, Gainesville, Florida.]

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92 Figure 5 4 Profile. [Reprinted with permission from Bloomquist, D. G. 201 1 BDK75 977 21 Progress Report 5 (Page 21 ). University of Florida, Gainesville, Florida.]

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93 Figure 5 5 Profile. [Reprinted with permission from Bloomquist, D. G. 2011. BDK75 9 77 21 Progress Report 5 (Page 22 ). University of Florida, Gainesville, Florida.]

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94 Figure 5 6 HDPE 36 Profile. [Reprinted with permission from Bloomquist, D. G. 2011. BDK75 9 77 21 Progress Report 5 (Page 23 ). University of Florida, Gainesville, Florida.]

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95 Figure 5 7 th End Quadrant 1 Profile. [Reprinted with permission from Bloomquist, D. G. 2011. BDK75 9 77 21 Progress Report 5 (Page 24 ). University of Florida, Gainesville, Florida.]

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96 Figure 5 8 Profile. [Reprinted with permission from Bloomquist, D. G. 2011. BDK75 977 21 Progress Repor t 5 (Page 25 ). University of Florida, Gainesville, Florida.]

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97 Figure 5 9 3 Profile. [Reprinted with permission from Bloomquist, D. G. 2011. BDK75 9 77 21 Progress Report 5 (Page 26 ). University of Florida, Gainesville, Florida. ]

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98 Figure 5 10 Profile. [Reprinted with permission from Bloomquist, D. G. 2011. BDK75 9 77 21 Progress Report 5 (Page 27 ). University of Florida, Gainesville, Florida.]

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99 Figure 5 11 th End Quadrant 1 Profile Unloading [Reprinted with permission from Bloomquist, D. G. 2011. BDK75 9 77 21 Progress Report 5 (Page 28 ). University of Florida, Gainesville, Florida.]

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100 Figure 5 12 Profile Unloading. [Reprinted with permission from B loomquist, D. G. 2011. BDK75 9 77 21 Progress Report 5 (Page 29 ). University of Florida, Gainesville, Florida.]

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101 Figure 5 13 Profile Unloading. [Reprinted with permission from Bloomquist, D. G. 2011. BDK75 9 77 21 Progress Report 5 (Page 30 ). University of Florida, Gainesville, Florida.]

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102 Figure 5 14 Profile Unloading. [Reprinted with permission from Bloomquist, D. G. 2011. BDK75 977 21 Progress Report 5 (Page 3 1). University of Florida, Gainesville, Florida.]

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103 Figure 5 15 th End Quadrant 1 Profile Unloading [Reprinted with permission from Bloomquist, D. G. 2011. BDK75 977 21 Progress Report 5 (Page 32 ). University of Florida, Gainesville, Florida.]

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104 Figure 5 16 HDPE 3 ant 2 Profile Unloading. [Reprinted with permission from Bloomquist, D. G. 2011. BDK75 9 77 21 Progress Report 5 (Page 33 ). University of Florida, Gainesville, Florida.]

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105 Figure 5 17 Profile Unloading. [Reprinted with permission from Bloomquist, D. G. 2011. BDK75 9 77 21 Progress Report 5 (Page 34 ). University of Florida, Gainesville, Florida.]

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106 Figure 5 18 Profile Unloading [Reprinted with permission from Bloomquist, D G. 2011. BDK75 9 77 21 Progress Report 5 (Page 35 ). University of Florida, Gainesville, Florida.]

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107 Figure 5 19 Quadrant orientations, viewing from East end to West end. [Reprinted with permission from Bloomquist, D. G. 2010. BDK 75 977 21 Progress Report 4 (Page 18, Figure 19 ). University of Florida, Gainesville, Florida.] Figure 5 20 Cone penetrometer testing apparatus. Photo credit: K. Pasken.

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108 Figure 5 21 Earth pressure cell layout for calibration test, with naming convention. [Reprinted with permission from Bloomquist, D. G. 2011. BDK75 9 77 21 Progress Report 5 (Page 37 ). University of Florida, Gainesville, Florida.]

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109 Figure 5 22 Name convention for earth pressure cells beneath plate s. [Reprinted with permission from Bloomquist, D. G. 2011. BDK75 977 21 Progress Report 5 (Page 37 ). University of Florida, Gainesville, Florida.]

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110 CHAPTER 6 CONCLUSION At the time of this thesis being written, two modifications were being made to how the calibration test was going to be performed. The calibration test had been started, and the soil box was pressurized to 15 psi. A cursory review of the data from the earth pressure cells revealed that the pressures being recorded beneath the four sm aller load plates were much less than those underne ath the six bigger load plates. A great deal of discussion prompted the following changes to be made: the ten earth pressure cells located beneath the center of the load plates would be embedded six inches beneath the soil surface. This would ensure that no errant readings would be output because of metal on metal forces between the earth pressure cells and the load plates. Secondly, the four smaller lift bags would be connected to a separate air supply, al lowing for higher pressurization of the smaller bags. In this way, the pressure being applied to the four smaller bags will be increased to a level where the pressures felt beneath the ten load plates will all be about the same. Because of the larger conta ct area present with the larger lift bags, the larger lift bags will not have to have as much pressure applied into them to exert the same pressure as the smaller lift bags. The data recorded and analyzed thus far shows very sma ll pipe deflections in the H DPE pipe material. Although this can be attributed to the discrepancy between applied and actual pressures, it is unlikely that the deflections will become much greater. Si nce the HDPE pipe material is the softest of the four materials being tested, the as sumption of the other pipe materials barely deflecting is being explored. If this is the case, there is the possibi lity of not having to test the aluminum and s tainles s s teel pipe materials.

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111 This research will prove to be very helpful in the making of guid elines for flexible pipe manufacturing. The goal is to be able to have a product which can withstand a variety of loading conditions, while at the same time operating effectively for the service life of the material. The FEM a nalysis to be performed will b e instrumental in simulating many different loading conditions so that such guidelines may be accurately provided.

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112 APPENDIX LITERATURE REVIEW An ongoing literature review is taking place throughout the duration of this project. The following pieces of literature, along with the references listed on the next page, have been reviewed as they pertain to the tasks being carried out. Brachman, R. W. I., Moore, I. D., and Rowe R. K. (2001) "The Performance of a Laboratory Facility for Evaluating the Structural Response of Small Diameter Buried Pipes." Can. Geotech. J. 38, 260 75 CleanFlow Systems (2010). "Analyzing the Accuracy of Profiler Equipm ent a nd Software." CleanFlow Systems (2010) "Profiler Reporting For Flexible Pipes." Moser, A. P. Buried Pipe Design. Second Edition McGraw Hill. New York, NY. Palmer, M (2005). "Results of Full Scale Test on 16 inch HDPE Pipe." Sargand, S M., and Masada T. (2002) "Soil Arching Over Deeply Buried Thermoplas tic Pipe."

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113 LIST OF REFERENCES Abolmaali, A (2008). "Experimental Verification of CUES Laser Profiler Deformation Analysis Results." University of Texas Arlington, T X Bloomquist, D. G. (2010). 21 Progress Report 2 Gainesville, FL. Bloomquist, D. G. (2010) of Florida, Gainesville, FL 21 Progress Gainesville, FL. Bloomquist D. G. (2011 ). 21 Progress Report 5 of Florida, Gainesville, FL Brachman, R. W. I., Moore, I. D., and Rowe R. K. (1996). "Interpretation of Buried Pipe Test: Small Di ameter Pipe in Ohio University Facility." Transportation Research Record 1541 64 75. Brachman, R. W. I., Moore, I. D., and Rowe R. K. (2000) "The Design of a Laboratory Facility for Evaluating the Structural Response of Small Diameter Buried P ipes." Can. Geotech. J. 37, 281 95. Motahari, A., and Forteza J. G. (2008) "Accuracy of Laser Profili ng of Flexible Pipes Using CUES System." University of Texas Arlington, TX. Smith, M. E., Beck, A., Thiel, R., and Metzler P. (2005) "Designing for Vertic al Pip e Deflection Under High Loads."

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114 BIOGRAPHICAL SKETCH Kenneth Andre w Pasken was born in 1987 in Miami, Florida. The youngest of three children, he grew up in Miami, Florida, graduating from Christopher Columbus High School in 2005. He held a p erfect attendance record throughout his four years in high school, in addition to being a member of a variety of honor societies. He decided to continue his educational career at the University of Florida, pursu ing an undergraduate degree in civil engineer ing with a minor in business a dministration. Throughout the summer months of his undergraduate college career, Kenneth worked as an intern with Pistorino & Alam Consulting Engineers, Inc. based out of Miami, FL. He performed a variety of duties, assisting members of inspection teams with whatever was necessary, including taking pictures, taking measurements, drawing up site sketches, reading building plans, researching building and fire safety codes, and performing other engineering related tasks. Going to school during the fall and spring months, then working and taking classes for his minor in business a dministration during the summer months, proved to be c hallenging but well worth the time invested. Kenneth earned his Bachelor of Science degree in c iv il engineering with a minor in business a dministration in December of 2009. He had already decided during the fall of 2009 e ngineering at the University of Florida. He will earn his Master of Engineering degree in civil engineering in May of 2011. ing employment in the field of civil e ngi neering, with inte rests in the g eotechni cal, structural, and t ransportation disciplines.