i
CERTIFICATION OF APPROVAL
Shear Strengthening of Reinforced Concrete (RC) T-beams
By
Nor Asnida Binti Md Husin 16957
A project dissertation submitted to the Civil Engineering Programme Universiti Teknologi PETRONAS in partial fulfilment of the requirement for the
BACHELOR OF ENGINEERING (Hons) (CIVIL)
Approved by,
_________________
(Dr. Teo Wee)
UNIVERSITI TEKNOLOGI PETRONAS
TRONOH, PERAK May 2015
ii
CERTIFICATION OF ORIGINALITY
This is to certify that I am responsible for the work submitted in this project, that the original work is my own except as specified in the references and acknowledgements, and that the original work contained herein have not been undertaken or done by unspecified sources or persons.
____________________________
NOR ASNIDA BINTI MD HUSIN
iii
ABSTRACT
Reinforced Concrete (RC) beams have been retrofitted with Fibre-Reinforced Polymer (FRP) composite externally in order to increase the strength. There are many researches regarding beams strengthened with FRP nowadays. However, there are still not enough aspects on behaviour of externally bonded FRP to RC beams. One of them is the effect of the interaction between internal shear reinforcement and externally bonded FRP. Besides that, the effect of shear reinforcement ratio is still questionable. Ten RC T-beams has been set up for this experimental program to study both of effect of two shear component and to determine the shear reinforcement ratio. The results of this experiment are obtained most likely similar with many other researchers which shows that the importance of internal steel stirrups and the effectiveness of externally bonded FRP. In addition, continuous wrap of FRP has greater FRP contribution to shear resistance as compared to small amount of FRP usage. This reflect the effectiveness of FRP based on the percentage of the usage.
iv
ACKNOWLEDGEMENT
Praise to Allah the Almighty for giving me the strength and patience to finish my Final Year Project Report.
I would like to take this opportunity to express my sincere and deepest gratitude to my Project Supervisor, Dr. Teo Wee for his guidance and feedback provided to me during the final year project process. I would like to thanks to Mr. Kilian Lau for helping me doing the project. The greatest thank to my beloved family for their prayers and support to me throughout this entire period of this Final Year Project 1 and 2. I would like to convey my biggest thanks to all technicians for supporting me throughout my project.
I especially would like to thank my parent, brothers and sisters for their support and encouragement. Without their prayers, continuous encouragement and moral support, this study would not be possible to complete.
I am also obligated to everyone who had directly and indirectly involve through contributions of ideas, as well as materials and professional opinions. Without anybody, I cannot achieve what I have done on final year report. Last but not least, I would like to thank everyone who directly or indirectly involved through contribution of ideas and materials as well as professional opinions until this project had been successfully done.
v
TABLE OF CONTENT
CERTIFICATION i
ABSTRACT iii
ACKNOWLEDGEMENT iv
CHAPTER 1: INTRODUCTION 1.1 Background of Study 1.2 Problem Statement 1.3 Objectives
1.4 Scope of Study 1.5 Significance of Study
1 3 4 5 5 CHAPTER 2: LITERATURE REVIEW
2.1 Introduction to FRP
2.1.1 Failure modes in FRP strengthened members 2.2 Steel Reinforcement
2.3 Bond Behaviour
6 8 11 12 CHAPTER 3: METHODOLOGY
3.0 Project Flow
3.1 Experimental Program 3.2 Materials and Methods 3.3 Process Flow of Experiment 3.4 Key Milestone
3.5 Gantt Chart
14 15 21 22 24 25
vi CHAPTER 4: RESULT AND DISCUSSION
4.1 Strength of Specimen and Percentage Gain Due to FRP 4.2 Deflection
26 28
CHAPTER 5: CONCLUSION AND RECOMMENDATIONS 33
REFERENCES 34
APPENDICES 36
vii LIST OF FIGURES
FIGURE 1. Strengthening configuration of external FRP 7
FIGURE 2. Failure modes in FRP 8
FIGURE 3. Diagonal shear crack 9
FIGURE 4. FRP sheet debonding followed by diagonal shear failure 9 FIGURE 5. FRP strips debonding followed by diagonal shear failure 9 FIGURE 6. Reinforcement types and yield strengths for 16 mm diameter bars 11
FIGURE 7. Project Flowchart 14
FIGURE 8. Design cross section of RC beams 17
FIGURE 9. TS0 17
FIGURE 10. TS0- CON 18
FIGURE 11. TS0- 0.5 18
FIGURE 12. TS0- 0.25 (1) 18
FIGURE 13. TS0- 0.5 (2) 19
FIGURE 14. TS 19
FIGURE 15. TS- CON 19
FIGURE 16. TS- 0.5 20
FIGURE 17. TS- 0.25 (1) 20
FIGURE 18. TS- 0.25 (2) 20
FIGURE 19. Side view of loading configuration 21
FIGURE 20. Process flow of experiment 22
FIGURE 21. Preparation of formwork 23
FIGURE 22. Testing using Hydraulic Actuator 23
FIGURE 23. Key Milestone 24
FIGURE 24. Crack patterns of the specimens 27
FIGURE 25. Load versus Deflection for beams without stirrups 29 FIGURE 26. Load versus steel strain for beams without stirrups 30 FIGURE 27. Load versus deflection for beams with stirrups 31 FIGURE 28. Load versus Steel Strain for beams with stirrups 31 LIST OF TABLES
TABLE 1. Mechanical properties of different composite materials 2
TABLE 2. Description of specimens 15
TABLE 3. Gantt Chart 25
TABLE 4. Experimental results 28
