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Figure 1 is a typical implementation concept. It illustrates how a precast column will be integrated with a precast sub-cap beam to form a precast bent.  Precast girders can then be erected on the sub-cap beam to complete the rapid construction phase. Following this, the deck slab and upper cap beam concrete can be placed to integrate the bent and superstructure to resist seismic loading. This construction will make use of fewer, larger reinforcing bars placed in generously sized ducts to facilitate construction. The overall concept emulates a type of cast-in-place bent construction used successfully in the Pacific Northwest for years.
Photo courtesy of the Precast/Prestressed Concrete Institute

Precast Bent System for High Seismic Regions: Laboratory Tests of Column-to-Footing Socket Connections

Publication No. FHWA-HIF-13-039
June 2013

Notice

This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The U.S. Government assumes no liability for the use of the information contained in this document. This report does not constitute a standard, specification, or regulation.

The U.S. Government does not endorse products or manufacturers. Trademarks or manufacturers’ names appear in this report only because they are considered essential to the objective of the document.

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Technical Report Documentation Page

1. Report No.
FHWA-HIF-13-039

2. Government Accession No. N/A

3. Recipient’s Catalog No.
N/A

4. Title and Subtitle
PRECAST BENT SYSTEM FOR HIGH SEISMIC REGIONS – LABORATORY TESTS OF COLUMN-TO-FOOTING SOCKET CONNECTIONS

5. Report Date
June 2013

6. Performing Organization Code

7. Author(s)
Olafur S. Haraldsson1, Todd M. Janes1, Marc O. Eberhard1, and
John F. Stanton1

8. Performing Organization Report No.

9. Performing Organization Name and Address
BergerABAM, Inc.
33301 Ninth Ave South, Suite 300
Federal Way, WA 98003

1 University of Washington, Seattle, WA

10. Work Unit No.

11. Contract or Grant No.
DTFH61-09-G-00005

12. Sponsoring Agency Name and Address
Federal Highway Administration
Highways for LIFE Program Office
1200 New Jersey Avenue, SE
Washington, DC 20590

13. Type of Report and Period Covered
Final Report

14. Sponsoring Agency Code

15. Supplementary Notes
This is a companion report to the final project report, Precast Bent System for High Seismic Regions (FHWA-HIF-13-037).

16. Abstract
This report provides detailed information from the laboratory investigation of three precast column-to-spread footing large-scale tests, including descriptions of the specimen design, testing, data reduction, and conclusions regarding the use of the connection with the precast bent system.

The tests provide data regarding the performance of the precast column-to-spread footing connection. The results indicate that the connection, when used with a precast column, is sufficiently strong to support the factored design gravity loads and to resist plastic hinging in the column above the footing. The behavior is emulative of cast-in-place performance. However, the precast column also provides an improved load path for lateral force transfer to the footing, owing to the elimination of outwardly hooked column longitudinal reinforcement. Additionally, the connection performance is adequate without reinforcement passing from the footing into the column, thus simplifying construction.

17. Key Words
Bridges, earthquakes, accelerated bridge construction, precast bent, connections, spread footing foundations, prefabricated bridge elements and systems

18. Distribution Statement
No restrictions. This document is available to the public through the National Technical Information Service, Springfield, VA 22161.

9. Security Classif. (of this report) Unclassified

20. Security Classif. (of this page) Unclassified

21. No. of Pages 184

22. Price


PREFACE

This report provides technical information from the laboratory testing of three precast column-to-spread footing specimens. These tests were conducted to support the development of a precast bent system for use in high seismic regions.

This report consists of seven chapters.

Chapter 1 provides background and overview material, including the spread footing socket connection concept and the research objective and scope.

Chapter 2 covers the design of the test specimens.

Chapter 3 provides a description of the test setup, instrumentation, and the method of control of the testing process.

Chapter 4 provides definition of the damage states that were observed and an overview of the damage progression that occurred during testing.

Chapter 5 provides the measured response of the three specimens, including material strengths, force and moment vs. displacement plots, curvature distributions, displacement histories, and strain histories. Strain histories are provided for all the principal reinforcement types. Also included are the results of the post-seismic tests of the axial capacity of the foundation.

Chapter 6 covers the analysis of the observed and recorded data, and it provides treatment of various modes of potential failure and how the test results compared relative to those failure modes.

Chapter 7 provides a summary, conclusions, and recommendations.

Appendixes are included to report more detailed information that may be useful in understanding the response of the specimens and the progression of damage

Approximate Conversions to SI Units
Symbol When You Know Multiply By To Find Symbol
Length
in inches 25.4 millimeters mm
ft feet 0.305 meters m
yd yards 0.914 meters m
mi miles 1.61 kilometers km
Area
in2 square inches 645.2 square millimeters mm2
ft2 square feet 0.093 square meters m2
yd2 square yard 0.836 square meters m2
ac acres 0.405 hectares ha
mi2 square miles 2.59 square kilometers km2
Volume
fl oz fluid ounces 29.57 milliliters mL
gal gallons 3.785 liters L
ft3 cubic feet 0.028 cubic meters m3
yd3 cubic yards 0.765 cubic meters m3
NOTE: volumes greater than 1000 L shall be shown in m3
Mass
oz ounces 28.35 grams g
lb pounds 0.454 kilograms kg
T short tons (2000 lb) 0.907 megagrams (or "metric ton") Mg (or "t")
Temperature (exact degrees)
°F Fahrenheit 5 (F-32)/9
or (F-32)/1.8
Celsius °C
Illumination
fc foot-candles 10.76 lux lx
fl foot-Lamberts 3.426 candela/m2 cd/m2
Force and Pressure or Stress
lbf poundforce 4.45 newtons N
lbf/in2 poundforce per square inch 6.89 kilopascals kPa

 

Approximate Conversions from SI Units
Symbol When You Know Multiply By To Find Symbol
Length
mm millimeters 0.039 inches in
m meters 3.28 feet ft
m meters 1.09 yards yd
km kilometers 0.621 miles mi
Area
mm2 square millimeters 0.0016 square inches in2
m2 square meters 10.764 square feet ft2
m2 square meters 1.195 square yards yd2
ha hectares 2.47 acres ac
km2 square kilometers 0.386 square miles mi2
Volume
mL milliliters 0.034 fluid ounces fl oz
L liters 0.264 gallons gal
m3 cubic meters 35.314 cubic feet ft3
m3 cubic meters 1.307 cubic yards yd3
Mass
g grams 0.035 ounces oz
kg kilograms 2.202 pounds lb
Mg (or "t") megagrams (or "metric ton") 1.103 short tons (2000 lb) T
Temperature (exact degrees)
°C Celsius 1.8C+32 Fahrenheit °F
Illumination
lx lux 0.0929 foot-candles fc
cd/m2 candela/m2 0.2919 foot-Lamberts fl
Force and Pressure or Stress
N newtons 02.225 poundforce lbf
kPa kilopascals 0.145 poundforce per square inch lbf/in2

* SI is the symbol for the International System of Units. Appropriate rounding should be made to comply with Section 4 of ASTM E380. (Revised March 2003)



TABLE OF CONTENTS

CHAPTER 1. INTRODUCTION
Need for Rapid Construction
Socket Connection Concept
Objectives and Scope

CHAPTER 2. DESIGN OF TEST SPECIMENS
Design of Prototype and Test Columns
Design of Prototype and Test Specimen Column-to-Footing Connection
Specimens SF-1 and SF-2
Specimen SF-3

CHAPTER 3. EXPERIMENTAL PROGRAM
Loading Setup
Instrumentation
Testing Protocol

CHAPTER 4. DAMAGE PROGRESSION
Definitions of Damage States
Preliminary Test Cycles
Factored Axial-Load Tests
Lateral-Load Tests (up to yielding)
Lateral-Load Tests (after yielding)
Axial-Load Testing to Collapse

CHAPTER 5. MEASURED RESPONSE
Material Properties
Concrete Strength
Grout Strength
Reinforcement
Friction Correction
Moment-Drift Response
Effective Force
Distribution of Column Curvature
Column Splice
Strains in Column Longitudinal Bars
Strain Profiles along the Height of Specimen
Strain Histories for Bars near Splice
Column Longitudinal Bar Strain Histories in Footing
Footing Strain Corrections
Strains in Bottom Mat of Footing Reinforcement
Strains in Bottom Bars in the North-South Direction (Loading Direction)
Implication of the Effective Width
Strains in Bottom Bars in the East-West Direction
Strains in Diagonal Bars
Strains in Footing Ties
Axial Load-Response
Factored Axial Loading
Ultimate Axial-Load Capacities

CHAPTER 6. ANALYSIS OF MEASURED RESPONSE

Footing Overturning
Footing Response
Footing Flexural Strength
Footing One-Way Shear Strength
Combined Punching Shear and Moment Transfer
Footing Punching Shear Strength
Footing Shear-Friction Strength
Footing Joint Shear
Column Response
Column Axial-Load Capacity
Column Flexural Strength
Column Shear Strength
Column Splice in Specimens SF-1 and SF-2
Damage Progression Models
Effective Stiffness Model
Normalized Moment-Drift Response
Strength Degradation
Energy Dissipation

CHAPTER 7. SUMMARY AND CONCLUSIONS

Summary
System Concept
Design of Test Specimens
Experimental Testing
Experimental Analysis
Conclusions
Recommendations

REFERENCES

APPENDIX A: SPECIMEN CONSTRUCTION DRAWINGS

Specimen SF-1
Specimen SF-2
Specimen SF-3

APPENDIX B: MATERIAL TESTS

Concrete Strength
Grout Strength
Reinforcement
Stress-Strain Plots for Specimens SF-1 and SF-2
Stress-Strain Plots for Specimen SF-3
Corrugated Metal Ducts

APPENDIX C: DAMAGE PROGRESSION

Specimen SF-1
Specimen SF-2
Specimen SF-3

APPENDIX D: CONSTRUCTION SEQUENCE

Specimen Construction Sequence

APPENDIX E: DESIGN CONCEPTS

Columns with Projecting Bars
Columns without Projecting Bars
Socket Columns
Long Struts
Short Struts


LIST OF FIGURES

Figure 1. Diagram. Rapid construction sequence

Figure 2. Diagram. Strut-and-tie models for (a) bent out bars and (b) headed bars

Figure 3. Photo. Earlier form of the socket connection used by the City of Redmond over Washington State SR 520, as originally used

Figure 4. Diagram. Precast column elevation for specimens SF-1 and SF-2

Figure 5. Diagram. Specimen SF-1 footing steel arrangement

Figure 6. Diagrams. Spread footing cross section for (a) SF-1 and (b) SF-2 (section A-4)

Figure 7. Graph. Final criteria design space for specimen SF-3

Figure 8. Diagram. Specimen SF-3 footing steel arrangement

Figure 9. Diagram. Specimen SF-3 spread footing cross-section (section A-5)

Figure 10. Diagram. Specimen SF-3 longitudinal section (section A-7)

Figure 11. Diagram. Test setup

Figure 12. Diagram. Locations of external instruments

Figure 13. Diagram. Locations of strain gauges in the three specimens

Figure 14. Diagram. Locations of strain gauges in the three specimens' cast-in-place footings

Figure 15. Graph. Lateral loading displacement history

Figure 16. Chart. Comparison of specimens' drift ratios for the major damage states

Figure 17. Diagram. Column vertical bar naming convention

Figure 18. Photos. Test specimens after a cycle of maximum drift ratio of 4.28 percent

Figure 19. Photo. Specimen SF-1 longitudinal bars fractured after one cycle to 10.65 percent drift ratio

Figure 20. Photo. Specimen SF-3 footing failure

Figure 21. Photo. Damage on top of footing after test

Figure 22. Diagram. Punching shear profile in the north-south direction (loading direction)

Figure 23. Photos. Specimens at the end of the test program

Figure 24. Equation. Coefficient of friction

Figure 25. Equation. Calculation of the moment at the base of the column

Figure 26. Diagram. Displacements and forces on test specimen used in figure 25

Figure 27. Graph. Specimen SF-1 moment-drift response

Figure 28. Graph. Specimen SF-2 moment-drift response

Figure 29. Graph. Specimen SF-3 moment-drift response

Figure 30. Equation. Effective lateral force

Figure 31. Graph. Specimen SF-1 effective force-displacement response

Figure 32. Graph. Specimen SF-2 effective force-displacement response

Figure 33. Graph. Specimen SF-3 effective force-displacement response

Figure 34. Equation. Calculating the average curvature

Figure 35. Graph. Specimen SF-1 average column curvature

Figure 36. Graph. Specimen SF-2 average column curvature

Figure 37. Graph. Specimen SF-3 average column curvature

Figure 38. Photo. Crack opening measurement pot

Figure 39. Graph. Specimen SF-1 splice interface opening

Figure 40. Graph. Specimen SF-2 splice interface opening

Figure 41. Graph. Strain profiles in S-SW bar in specimen SF-1

Figure 42. Graph. Strain profiles in S-SW bar in specimen SF-2

Figure 43. Graph. Strain profiles in S-SW bar in specimen SF-3

Figure 44. Graphs. Strain-drift relationship 2 inches below the column splice interface

Figure 45. Graphs. Strains in N-NE bars in specimens SF-1 and SF-2 at various heights below the interface

Figure 46. Graphs. Strains in S-SW bars in specimen SF-1 and SF-2 at various heights below the interface

Figure 47. Graphs. Strains in N-NE and S-SW bars in Specimen SF-3 at various locations below the interface

Figure 48. Graph. Thermal effects in strain gauges

Figure 49. Graph. Specimen SF-1 strain profiles in bottom mat of the footing

Figure 50. Graph. Specimen SF-2 strain profiles in bottom mat of the footing

Figure 51. Graph. Specimen SF-3 strain profiles in bottom of the footing

Figure 52. Graph. Specimen SF-1 transverse strains in bottom mat of the footing

Figure 53. Graph. Specimen SF-2 transverse strains in bottom mat of the footing

Figure 54. Graph. Specimen SF-3 transverse strains in bottom mat of the footing

Figure 55. Graph. Specimen SF-1 strains in diagonal steel in footing

Figure 56. Graph. Specimen SF-2 strains in diagonal steel in footing

Figure 57. Graph. Specimen SF-3 strains in diagonal steel in footing

Figure 58. Graph. Specimen SF-1 strains in ties

Figure 59. Graph. Specimen SF-2 strains in ties

Figure 60. Graph. Specimen SF-3 strains in ties

Figure 61. Graph. Column vertical displacement vs. cumulative column drift

Figure 62. Graph. Axial response of specimens SF-1 and SF-2

Figure 63. Photo. Specimen SF-2 after axial load of 817 kips

Figure 64. Diagram. Support conditions

Figure 65. Equation. Shear stress demand

Figure 66. Equation. Nominal shear capacity

Figure 67. Equation. Nominal punching shear capacity including transverse steel

Figure 68. Equation. Nominal punching shear capacity excluding transverse steel

Figure 69. Equation. Nominal shear friction resistance

Figure 70. Equation. Maximum principal compressive stress

Figure 71. Equation. Maximum principal tensile stress

Figure 72. Equation. Principal tensile stress

Figure 73. Equation. Principal compressive stress

Figure 74. Diagrams. Strut and tie models for bent-out bars (left) and headed bars (right)

Figure 75. Photo. Joint region of specimen SF-3 after failure

Figure 76. Equation. Nominal axial-load capacity of the column

Figure 77. Graph. Moment-curvature model.(15)

Figure 78. Equation. Plastic overstrength shear demand

Figure 79. Equation. Nominal shear resistance

Figure 80. Equation. Component of total shear resistance due to concrete strength

Figure 81. Equation. Concrete shear resistance

Figure 82. Equation. Contribution of total shear resistance due to transverse steel strength

Figure 83. Equation. Analytical plastic hinge length

Figure 84. Equation. Damage model for spalling

Figure 85. Equation. Damage model for bar buckling

Figure 86. Equation. Damage model for bar fracture

Figure 87. Equation. Effective modulus of rigidity

Figure 88. Graphs. Normalized equivalent moment-drift response

Figure 89. Graph. Comparison of effective force vs. drift

Figure 90. Equation. Energy dissipation

Figure 91. Graphs. Calculated energy dissipation per cycle (top), and calculated cumulative energy dissipation (bottom)

Figure 92. Graph. Equivalent viscous damping calculated per cycle

Figure 93. Equation. Equivalent viscous damping

Figure 94. Graph. Equivalent viscous damping vs. drift

Figure 95. Photos. Specimen SF-1 (left) and specimen SF-2 (right)

Figure 96. Diagram. Specimen SF-1 column elevation and sections

Figure 97. Diagram. Specimen SF-1 top mat plan view

Figure 98. Diagram. Specimen SF-1 bottom mat plan view

Figure 99. Diagram. Specimen SF-1 sections

Figure 100. Diagram. Specimen SF-2 column elevation and sections

Figure 101. Diagram. Specimen SF-2 top mat plan view

Figure 102. Diagram. Specimen SF-2 bottom mat plan view

Figure 103. Diagram. Specimen SF-2 sections

Figure 104. Diagram. Specimen SF-3 column sections

Figure 105. Diagram. Specimen SF-3 column elevation

Figure 106. Diagram. Specimen SF-3 bottom mat plan view

Figure 107. Diagram. Specimen SF-3 footing sections A7 and A6

Figure 108. Diagram. Specimen SF-3 footing sections A5 and B5

Figure 109. Equation. Calculating yield strain

Figure 110. Graph. Specimens SF-1/SF-2 stress-strain curves for No. 6 bars

Figure 111. Graph. Specimens SF-1/SF-2 stress-strain curve for No. 5 bar

Figure 112. Graph. Specimens SF-1/SF-2 stress-strain curve for No. 4 bar

Figure 113. Graph. Specimens SF-1/SF-2 stress-strain curves for No. 3 bar

Figure 114. Graph. Specimens SF-1/SF-2 stress-strain curves for stirrups (2-gauge wire)

Figure 115. Graph. Specimens SF-1/SF-2 stress-strain curves for spiral reinforcement (3-gauge wire)

Figure 116. Graph. Specimen SF-3 stress-strain curve for No. 7 bar

Figure 117. Graph. Specimen SF-3 stress-strain curve for No. 6 bar

Figure 118. Graph. Specimen SF-3 stress-strain curve for No. 5 bar

Figure 119. Graph. Specimen SF-3 stress-strain curve for No. 4 bar

Figure 120. Graph. Specimen SF-3 stress-strain curve for No. 3 bar

Figure 121. Photo. Corrugated metal duct used in test specimens

Figure 122. Photo. Specimen SF-1 flexural cracks after cycle 4-1 (+1.00/-1.00 target drift ratio)

Figure 123. Photo. Specimen SF-1: first significant spalling at cycle 6-2 (+2.48/-2.48 target drift ratio)

Figure 124. Photo. Specimen SF-1: plastic hinge became more pronounced in subsequent cycles. Photo taken during cycle 8-1 (+4.28/-4.28 target driftratio)

Figure 125. Photo. Specimen SF-1: first noticeable bar buckling was the N-NW bar in cycle 9-2 (+7.40/-7.40 target drift ratio)

Figure 126. Photo. Specimen SF-1: N-NE bar fractured first when the column was loaded to peak in cycle 10-2 (+10.65/-10.65 target drift ratio)

Figure 127. Photo. Specimen SF-1: damage after the cyclic testing

Figure 128. Photo. Specimen SF-1: no damage to the footing was observed after the cyclic testing

Figure 129. Photo. Specimen SF-1: damage the end of testing. The column crushed after application of vertical load of 842 kips

Figure 130. Photo. Specimen SF-2: flexural cracks after cycle 3-2 (+0.83/-0.83 target drift ratio)

Figure 131. Photo. Specimen SF-2: first significant spalling at cycle 7-1 (+2.97/-2.97 target drift ratio)

Figure 132. Photo. Specimen SF-2: the column fully spalled after cycle 8-1 (+4.28/-4.28 target drift ratio)

Figure 133. Photo. Specimen SF-2: first noticeable bar buckling was the N-NW bar in cycle 9-3 (+7.40/-7.40 target drift ratio)

Figure 134. Photo. Specimen SF-2: N-NW bar fractured first when the column was being loaded to peak in cycle 10-2 (+10.65/-10.65 target driftratio)

Figure 135. Photo. Specimen SF-2: damage after the cyclic testing

Figure 136. Photo. Specimen SF-2: no damage to the footing was observed after the cyclic testing

Figure 137. Photo. Specimen SF-2: damage the end of testing. The column crushed after application of vertical load of 819.5 kips

Figure 138. Photo. Specimen SF-3: significant horizontal crack in cycle 3-1 (+0.69/-0.69 target drift ratio)

Figure 139. Photo. Specimen SF-3: separation at column-footing interface in cycle 5-3 (+1.72/-1.72 target drift ratio)

Figure 140. Photo. Specimen SF-3: first diagonal cracking in cycle 6-1 (+2.06/-2.06 target drift ratio)

Figure 141. Photo. Specimen SF-3: first column spalling in cycle 6-2 (+2.48/-2.48 target drift ratio)

Figure 142. Photo. Specimen SF-3: radial footing crack propagation in cycle 6-2 (+2.48/-2.48 target drift ratio)

Figure 143. Photo. Specimen SF-3: large horizontal crack in cycle 6-2 (+2.48/-2.48 target drift ratio)

Figure 144. Photo. Specimen SF-3: large column flexural cracks occurring in cycle 7-2 (+3.57/-3.57 target drift ratio)

Figure 145. Photo. Specimen SF-3: full column spalling in cycle 9-1 (+6.16/-6.16 target drift ratio)

Figure 146. Photo. Specimen SF-3: first footing spalling in cycle 9-2 (+7.40/-7.40 target drift ratio)

Figure 147. Photo. Specimen SF-3: transverse steel exposed in cycle 9-3 (+7.40/-7.40 target drift ratio)

Figure 148. Photo. Specimen SF-3: first exposure of longitudinal reinforcement in cycle 9-3 (+7.40/-7.40 target drift ratio)

Figure 149. Photo. Specimen SF-3: fracture of transverse reinforcement in cycle 10-1 (+8.87/-8.87 target drift ratio)

Figure 150. Photo. Specimen SF-3: major footing spalling occurring in cycle 10-1 (+8.87/-8.87 target drift ratio)

Figure 151. Photo. Specimen SF-3: major cracks in the concrete core in cycle 10-2 (+10.65/-10.65 target drift ratio)

Figure 152. Photo. Specimen SF-3: condition of specimen just before last cycle

Figure 153. Photo. Specimen SF-3: column after punching through in last cycle (cycle 10-3, +10.65/-10.65 target drift ratio)

Figure 154. Photo. Specimen SF-3: column after punching though in last cycle (cycle 10-3, +10.65/-10.65 target drift ratio)

Figure 155. Photo. Column segments for specimens SF-1 and SF-2 were match-tied at a bridge construction site in the City of Redmond

Figure 156. Photo. Roughened surface of octagonal, bottom portion of column

Figure 157. Photo. Specimens SF-1 and SF-2, column segments formed and ready to be cast

Figure 158. Photo. Specimen SF-3, column formed and ready to be cast

Figure 159. Photo. Specimen SF-1 footing ready to be cast

Figure 160. Photo. Specimen SF-3 footing formwork and reinforcement

Figure 161. Photo. Specimen SF-3 column inserted into footing that is ready to cast

Figure 162. Photo. Specimen SF-3: finishing the footing surface

Figure 163. Diagram. Column detail with projecting bars

Figure 164. Diagram. Socket column concept

Figure 165. Diagram. Long struts concept

Figure 166. Diagram. Short struts concept



List of Tables

Table 1. Strain gauge types used in the specimens

Table 2. Target displacement history

Table 3. Damage state description

Table 4. Damage milestones for all three specimens

Table 5. Average concrete strength on test day

Table 6. Average grout strength on test day

Table 7. Measured mild reinforcement properties

Table 8. Moments and drift ratios at maximum and 80 percent of maximum resistance

Table 9. Effective force and displacement at maximum and 80 percent of maximum resistance

Table 10. Axial load and strains across and near splice interfaces

Table 11. Axial load combinations on the test specimens

Table 12. External forces, displacements, and estimated reactions.

Table 13. Footing flexural capacities and demands

Table 14. Footing one-way strength capacities and demands

Table 15. Combined punching shear and moment transfer capacities and demands

Table 16. Punching shear capacities and demands

Table 17. Footing shear-friction capacities and demands

Table 18. Footing joint shear stress capacities and demands

Table 19. Column axial-load capacities and demands

Table 20. Column flexural capacities and demands

Table 21. Column shear capacities and demands

Table 22. Comparison of damage model predictions and observed occurrences

Table 23. Comparison of model prediction and measured effective modulus of rigidity

Table 24. Summary of ratios of footing demands to calculated capacities

Table 25. Slump and air content test results

Table 26. Concrete compressive strengths up to 28 days

Table 27. Concrete compressive strengths on test day

Table 28. Concrete split cylinder strengths on test day.1

Table 29. Grout cube strength on test day

Table 30. Measured mild reinforcement properties



LIST OF ABBREVIATIONS AND ACRONYMS

AASHTO American Association of State Highway and Transportation Officials
ABC Accelerated Bridge Construction
ACI American Concrete Institute
ASCE American Society of Civil Engineers
BDM Bridge Design Manual
Caltrans California Department of Transportation
CCC Compression-compression-compression
DL Dead load
HSS Hollow structural section
LL Live load
LRFD Load and Resistance Factor Design
LVDT Linear variable differential transformer
MEF Maximum effective force
NEHRP National Earthquake Hazards Reduction Program
o.c. On center
o.d. Outside diameter
OT Overturning
PEER Pacific Earthquake Engineering Research
PTFE Polytetrafluoroethylene
SDC Seismic Design Criteria
WSDOT Washington State Department of Transportation
Page last modified on July 30, 2013.
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