Experimental Study on Residual Capacity of Marine Steel/Composite Joint after Fatigue Damage

H-type steel/ composite joint is taken as the research object on the fatigue effect. Based on the whole process of crack initiation and propagation in the process of fatigue cumulative damage of the H-type hybrid joint, and the analysis of residual ultimate bearing capacity and failure mode of the hybrid joint, finally, the influence mechanism of fatigue cumulative damage on the failure of hybrid joints is revealed. The results show that the fatigue cumulative effect does not depend on the appearance of macro-cracks, but depends on the irreversible residual deformation. The fatigue cumulative effect will lead to a significant reduction of the bearing capacity of hybrid joints, and the higher the cumulative damage, the weaker the initial fatigue load level. After fatigue damage, the joint shows a strong fatigue continuation damage pattern, starting from the fatigue crack tip, and continuing to crack along the interface between the skin and the sandwich layer, until complete failure. © 2020, Editorial Office of Ship Building of China. All right reserved.