A Numerical Study on Fatigue Crack Growth of Cracked Steel Plate Reinforced by Shape Memory Alloy (SMA) Plate and CFRP

CFRP (Carbon Fiber-reinforced Polymer) and SMA (Shape memory alloy) are two excellent materials to improve the fatigue life of cracked steel structures, which can achieve better effect with prestress. By thermally activating constrained SMA, prestress can be generated, which is of great importance in the fatigue strengthening of steel members. Compared with SMA wire, SMA plate will have greater recovery stress when activated. In this study, SMA plate, SMA plate and CFRP are used for double-sided reinforcement of steel plate with a central crack. SMA plate is fixed on steel plate by fixture, and CFRP is pasted. The process of using SMA plate and CFRP to strengthen cracked steel plates were simulated by finite element method, the width of SMA plates are considered in the simulation process. The numerical simulation results show that the reinforcement effect is better with the increase of the width direction of SMA plates. What’s more, the reinforcement effect of CFRP and SMA plate is much better than that of SMA plate only.