Numerical study of fatigue life of SMA/CFRP patches retrofitted to central-cracked steel plates

Abstract

This study aims to evaluate the repair performance of central-notched steel plates reinforced by the self-prestressing shape memory alloy carbon fiber reinforced polymer patching system (SMA/CFRP patch) through the numerical and theoretical study of the fatigue life after experimental fatigue life results were validated with the numerical method. These methods were used to determine the effectiveness of the reinforcing technique. Different widths of SMA/CFRP patches, elastic modulus of CFRP, prestress level, initial damage degree and crack type were considered as parameters that influenced the repair effectiveness. The outcomes showed that the increase in the Young’s modulus, prestress level and width could significantly improve the fatigue life of central-notched steel plates. The effect of the prestress level was more prominent with wider width. Good agreement with the test data revealed that numerical and theoretical methods could predict the fatigue life with reasonable accuracy, and the strengthening was more effective for edge-cracked specimens than central-cracked specimens.