COMPARATIVE ANALYSIS OF BAGAMBANG BRIDGE VOIDED SLAB DECK AND BOX GIRDER DECK USING
FINITE ELEMENT ANALYSIS SOFTWARE
GERRY VINCENT VERGARA LIWAG 2005-48602
SUBMITTED TO THE FACULTY OF THE
COLLEGE OF ENGINEERING AND AGRO-INDUSTRIAL TECHNOLOGY UNIVERSITY OF THE PHILIPPINES LOS BAÑOS
IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE
DEGREE OF
BACHELOR OF SCIENCE IN CIVIL ENGINEERING
APRIL 2010
UNIVERSITY OF THE PHILIPPINES LOS BAÑOS College of Engineering and Agro-Industrial Technology
Department of Civil Engineering
COMPARATIVE ANALYSIS OF BAGAMBANG BRIDGE VOIDED SLAB DECK AND BOX GIRDER DECK USING
FINITE ELEMENT ANALYSIS SOFTWARE
GERRY VINCENT VERGARA LIWAG
BACHELOR OF SCIENCE IN CIVIL ENGINEERING
APRIL 2010
TABLE OF CONTENTS
Title Page i
Acceptance Sheet ii
About the Author iii
Acknowledgement iv
Table of Contents v
List of Tables viii
List of Figures ix
1. INTRODUCTION 1.1 Background of the Study 1
1.2 Significance of the Study 3
1.3 Objective of the Study 3
1.4 Scope and Limitations of the Study 4
1.5 Date and Place of the Study 4
2. REVIEW OF RELATED LITERATURE 2.1 Bridge Deck 5
2.1.1 Slab Type Bridge Deck 5
2.1.1.1 Solid Deck Slab 5 2.1.1.2 Voided Deck Slab 6
2.1.2 Beam and Slab Type Bridge Deck 7
2.1.2.1 T-Beam Bridge Deck 7
2.1.2.2 I-Girder Bridge Deck 8
2.1.3 Cellular Type Bridge Deck 8
2.1.3.1 Multicellular Bridge Deck 9
2.1.3.2 Box Girder Bridge Deck 9
2.2 Materials of Bridge Deck Construction 10
2.2.1 Concrete 10
2.2.1.1 Fresh Concrete 11
2.2.1.2 Hardened Concrete 11
2.2.2 Steel Reinforcement 11
2.2.3 Formworks 12
2.2.3.1 Exterior Grade Waterproof Plywood 12
2.2.3.2 Waterproof Particle Board 13
2.2.3.3 Steel Form 13
2.2.4 Falsework 13
2.2.5 Scaffoldings 14
2.2.5.1 Independent Pole Scaffolds 14
2.2.5.2 Cantilever Scaffolds 14
2.3 Lifting Equipment 14
2.3.1 Wheel Mounted Cranes 15
2.3.2 Crawler Mounted Cranes 15
2.3.3 Girder Launchers 15
2.4 Types of Loads Acting on Bridge Deck 15
2.4.1 Dead Load 15
2.4.2 Live Load 16
2.4.3 Impact Load 17
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2.4.4 Wind Load 17
2.5 Finite Element Analysis 17
2.5.1 Concept of Finite Element Analysis 18
2.5.2 Finite Element Formulation 19
2.5.2.1 Truss Element 19
2.5.2.2 Flexure Element 20
2.5.2.3 Triangular Element 21
2.5.2.4 Quadrilateral Element 22
2.5.3 Steps in Finite Element Analysis 23
2.5.4 Finite Element Analysis Software 24
3. STUDY METHODOLOGY 26
4. OBSERVATIONS
4.1 Preparation of Falseworks 27
4.1.1 Stabilizing the Ground Base Support 27
4.1.2 Erection of the Shoring Frames 28
4.2 Installation of Formworks 30
4.2.1 Laying out of Joists 30
4.2.2 Placing of Deck Forms 31
4.3 Installation of Reinforcing Bars and Polystyrene Void Formers 32
4.3.1 Bottom Bars 32
4.3.2 Placing of Polystyrene Void Formers 34
4.3.3 Top Bars 35
4.4 Placing of Concrete 36
4.4.1 Transit Mixers 37
4.4.2 Pumpcrete 38
4.4.3 Vibrators 38
4.4.4 Duration of Concreting and Temperature 38
4.5 Curing of Concrete 39
4.6 Removal of Formworks and Falseworks 39
5. DISCUSSION AND ANALYSIS
5.1 Modeling of the Bridge Voided Slab Deck and Box Girder Deck 40
5.1.1 Assumptions in Creating the Models 41
5.1.2 Features and Data Needed in Creating the Model 41
5.1.3 Steps in Creating the Model 43
5.2 Moving Load Analysis of the Voided Slab Deck and Box Girder Deck 45
5.2.1 Bridge Deck Loading 46
5.2.1.1 Dead Load Case 46
5.2.1.2 Moving Live Load Case 46
5.2.2 Results of Moving Load Analysis 47
5.2.2.1 Behavior of the Voided Slab Deck and Box Girder Deck
Subjected to Dead Load 47
5.2.2.2 Behavior of the Voided Slab Deck and Box Girder Deck
Subjected to Moving Live Load 54
5.2.3 Summary of the Results in the Analysis and Comparison Voided Slab Deck and Box Girder Deck of Deck under
Dead and Moving Live Loads 59
5.3 Truck Loading Simulation on the Voided Slab Deck 62
5.3.1 Multi-Step Static Analysis 62 5.3.2 Displacement of Voided Slab Deck under Simulation of
Truck Loading 62
5.3.2 Moments in Voided Slab Deck under Simulation of Truck Loading 63 5.4 Comparison of Voided and Box Girder Deck in Terms of Cross
Sectional Area 64
6. CONCLUSION 66
7. RECOMMENDATIONS 68
REFERENCES 69
APPENDICES 71
Appendix A. Bagambang Bridge General Notes 71 Appendix B. Bagambang Bridge Deck Cross-Section and Bar Schedule 72 Appendix C. Plan View of Bagambang Bridge Superstructure 73 Appendix D. Bagambang Bridge Abutment A Dimension 74
Appendix E. General Plan of Bagambang Bridge 75
Appendix F. Log File Output in the Analysis of Voided Slab
Deck Bridge Using SAP2000 76
Appendix G. Log File Output in the Analysis of Box Girder
Deck Bridge Using SAP2000 79
Appendix H-1. Maximum Positive and Negative Moments in
Each Girder for Voided Slab Deck under Dead Load 81 Appendix H-2. Maximum Positive and Negative Moments in Each
Girder for Voided Slab Deck under Moving Live Load 82 Appendix I. Maximum Positive and Negative Moments in Each Girder
for Box Girder Deck under Dead and Moving Live Load 83 Appendix J. Maximum Tensile and Compressive Stress in Each Part
of Voided Slab Deck under Dead and Moving Live Load 84 Appendix K. Maximum Tensile and Compressive Stress in Each Part of
Box Girder Deck under Dead and Moving Live Load 85 Appendix L. Steps in Truck Loading Simulation 86 Appendix M. Computation of the Cross Sectional Area of Voided Slab Deck 88 Appendix N. Computation of the Cross Sectional Area of Box Girder Deck 89
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LIST OF TABLES
Table No. Title Page No.
Table 2-3 Unit weight of different materials 16 Table 5-1 Required dimensions in the modeling of voided slab deck bridge 42
Table 5-2 Maximum displacements between two decks 60
Table 5-3 Maximum stress at the top part between two decks 60 Table 5-4 Maximum stress at the bottom part between two decks 61 Table 5-5 Net cross sectional area between voided slab and box girder deck 65 Table H-1 Maximum positive and negative moments in voided slab deck
under dead load 81
Table H-2 Maximum positive and negative moments in voided slab deck
under moving live load 82
Table I-1 Maximum positive and negative moments in box girder deck
under dead load 83
Table I-2 Maximum positive and negative moments in box girder deck
under moving live load 83
Table J-1 Maximum tensile and compressive stress in voided slab deck
under dead load 84
Table J-2 Maximum tensile and compressive stress in voided slab deck
under moving live load 84
Table K-1 Maximum tensile and compressive stress in box girder deck
under dead load 85
Table K-2 Maximum tensile and compressive stress in box girder deck
under moving live load 85
LIST OF FIGURES
Figure No. Title Page No.
Figure 1-1. Bagambang structures being constructed 2
Figure 2-1. Solid deck slab cross-section 6
Figure 2-2. Voided slab cross-section 7
Figure 2-3. T-beam deck cross-section 8
Figure 2-4. I-girder deck cross-section 8
Figure 2-5. Multicellular deck cross-section 9
Figure 2-6. Box girder cross-section 10
Figure 2-7. HS20-44 trucks 16
Figure 2-8. Model of a flat bracket with different element types 18
Figure 2-9. Truss element 19
Figure 2-10. Flexure element 20
Figure 2-11. Triangular element 22
Figure 2-12. Quadrilateral element 23
Figure 4-1. Steel shoe pads supporting the feet of the H-frames 28
Figure 4-2. The shoring frames 28
Figure 4-3. Cross bracings and G.I. pipes holding the H-frames 29
Figure 4-4. U-head channels for upper H-frames 30
Figure 4-5. Joists of the bottom formworks 31
Figure 4-6. Phenolic plywoods used as deck forms 31
Figure 4-7. Bended steel bars 32
Figure 4-8. Cone/tie assembly system 33
Figure 4-9. Installation of stirrups 34
Figure 4-10. Cylindrical polystyrene used as void formers 34
Figure 4-11. Strapping of polystyrene 35
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Figure 4-12. G.I. pipes concrete screeders 36
Figure 4-13. Deck formwork ready for concreting 37
Figure 4-14. The transit mixer 37
Figure 4-15. Pumpcrete used for concreting 38
Figure 5-1. Cross-section of the voided slab deck 40
Figure 5-2. Typical five cell cast in place cross section 42
Figure 5-3. Bridge deck shell model using SAP2000 44
Figure 5-4. Voided slab deck solid model using SAP2000 44
Figure 5-5. Box girder deck shell model 45
Figure 5-6. Solid model of box girder deck 45
Figure 5-7. Lanes of the Bagambang Bridge in each direction 47
Figure 5-8. Standard HS20-44 truck and its lane loading 48
Figure 5-9. Deformed shape decks of two bridges 49
Figure 5-10. Displacement contour of the decks 49
Figure 5-11. Top stress contour of deck 51
Figure 5-12. Bottom stress contour of deck 52
Figure 5-13. Top stress at the left side of the voided slab deck 53
Figure 5-14. Bottom stress at the right side of the voided slab deck 53
Figure 5-15. Displacement contour of deck under moving live loads 55
Figure 5-16. Stress contour at the top surface of voided slab deck 56
Figure 5-17. Stress diagram of the top left part of voided slab deck 57
Figure 5-18. Stress contour at the bottom surface of the voided slab deck 58
Figure 5-19. Stress diagram of the bottom right part of the voided slab deck 58
Figure 5-20. Simulation of deck loading 63
Figure 5-21. Moment diagram of interior girder 10 for step 18 63
Figure 5-22. Moment diagram of interior girder 17 for step 14 64
Figure M-1. Cross Section of voided slab deck 88
Figure N-1. Cross section of box girder deck 89
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