Reinforcement corrosion is always a serious caused that lead to reducing strength and ductility of reinforcing bars, especially in bridges. This research examines the seismic performance of corroded wall piers (squat walls) and developed models for evaluating the seismic behavior of corroded squat walls. To observe the seismic behavior of corroded members, cyclic tests of large-scale wall specimens are conducted. The locations of
corrosion are examined only on the middle of the exterior of the walls which might be exposed directly to the corrosive causes. Accelerated corrosion using electrochemical method is used to impose corrosion to steel reinforcement. After the corrosion process, the wall will be tested using cyclic loading to examine the seismic performance. The wall after testing is demolished to investigate the corrosion condition of steel reinforcement.
Methods to estimate the residual shear strength of reinforced concrete squat walls with corroded reinforcement are proposed. Shear strength estimation based on average weight loss and minimum residual cross sectional area produces results that more reasonably described the experimental behavior. Empirical equations to estimate the residual beam flexural strength of corroded RC squat walls are proposed. A new evaluation method for shear strength and ultimate displacement was proposed in this research. Comparison with test results showed that the proposed method can capture the residual shear strength and ultimate displacement capacity of corroded squat walls
examined in this research.

Reinforcement corrosion is always a serious caused that lead to reducing strength and ductility of reinforcing bars, especially in bridges. This research examines the seismic performance of corroded wall piers (squat walls) and developed models for evaluating the seismic behavior of corroded squat walls. To observe the seismic behavior of corroded members, cyclic tests of large-scale wall specimens are conducted. The locations of
corrosion are examined only on the middle of the exterior of the walls which might be exposed directly to the corrosive causes. Accelerated corrosion using electrochemical method is used to impose corrosion to steel reinforcement. After the corrosion process, the wall will be tested using cyclic loading to examine the seismic performance. The wall after testing is demolished to investigate the corrosion condition of steel reinforcement.
Methods to estimate the residual shear strength of reinforced concrete squat walls with corroded reinforcement are proposed. Shear strength estimation based on average weight loss and minimum residual cross sectional area produces results that more reasonably described the experimental behavior. Empirical equations to estimate the residual beam flexural strength of corroded RC squat walls are proposed. A new evaluation method for shear strength and ultimate displacement was proposed in this research. Comparison with test results showed that the proposed method can capture the residual shear strength and ultimate displacement capacity of corroded squat walls
examined in this research.

TABLE OF CONTENTS
ABSTRACT II
ACKNOWLEDGMENT IV
LIST OF TABLES IX
LIST OF FIGURE X
CHAPTER 1- INTRODUCTION 14
1.1 BACKGROUND 14
1.2 OBJECTIVES AND SCOPES 15
1.3 OUTLINE 15
CHAPTER 2– LITERATURE REVIEW 17
2.1 CORROSION OF STEEL IN CONCRETE 17
2.1.1 CORROSION OF STEEL IN CONCRETE 17
2.1.2 EFFECT OF CORROSION ON MATERIAL PROPERTIES 23
2.1.3 EXAMINATION OF PREVIOUS EXPERIMENTAL RESEARCH 33
2.2 SHEAR STRENGTH PREDICTION OF SQUAT WALL 35
2.2.1 CRACKING SHEAR STRENGTH 35
2.2.2 SHEAR STRENGTH 37
2.2.3 DEFLECTION 46
2.2.4 POST STRENGTH POINT 49
2.3 SHEAR FRICTION 50
2.3.1 ACI 318 CODE BASED ON SHEAR-FRICTION METHOD 50
2.3.2 MODIFIED SHEAR-FRICTION METHOD 52
CHAPTER 3– SPECIMEN DESIGN AND EXPERIMENTAL PROGRAM 54
3.1 SPECIMEN DESIGN 54
3.2 MATERIAL 56
3.2.1 CODE REQUIREMENTS FOR MATERIAL PROPERTIES 56
3.2.2 CONCRETE: 57
3.2.3 STEEL: 58
3.3 CODE REQUIREMENTS FOR SHEAR WALL DESIGN 60
3.3.1 WEB REINFORCEMENT RATIOS REQUIREMENTS 60
3.3.2 GEOMETRIC REQUIREMENTS 61
3.3.3 SHEAR STRENGTH CALCULATION AND REQUIREMENTS 62
3.3.4 SHEAR FRICTION CALCULATION AND REQUIREMENTS 63
3.4 SPECIMEN MANUFACTURE: 64
3.5 ACCELERATED CORROSION 65
3.5.1 ACCELERATED CORROSION DESIGN: 65
3.5.2 SMALL CORROSION TESTS: 65
3.6 CORROSION PROCESS OF WALL SPECIMENS: 68
3.7 CYCLIC TESTING 70
CHAPTER 4- TEST RESULT AND ANALYSIS 73
4.1 CYCLIC TEST RESULT 73
4.1.1 DAMAGE DISTRIBUTION 73
4.1.2 HYSTERESIS LOOPS OF SPECIMENS 83
4.1.3 DAMPING RATIO OF SPECIMENS 85
4.2 CORROSION TEST RESULT 87
CHAPTER 5- CONCLUSION AND SUGGESTION 89
5.1 CONCLUSIONS 89
5.2 SUGGESTIONS 91
REFERENCES 92

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