Numerical investigation on the residual ultimate strength of cracked stiffened plates under extreme cyclic loads

This paper aims at gaining insights on the load-carrying behavior of stiffened plate under cyclic loads. Non-linear finite element method is employed to investigate the residual ultimate strength of cracked stiffened plate. Assuming that the precrack is a transverse and through-thickness crack and exists only in the plate or both in the stiffener and the plate, the corresponding four types of crack location models are analyzed. The crack propagation caused by extreme cyclic loads is considered in the present study. The crack growth process is simulated by adopting the element erosion approach. The effects of the amplitude of cyclic loads, crack location, the plate aspect ratio, the plate thickness as well as the stiffener size on the ultimate strength of cracked stiffened plate under cyclic loads are examined. The ultimate strength of cracked stiffened plate under monotonously increasing load is studied for comparative analysis. Based on the numerical results, a relationship between the number of cycles and non-dimensional ultimate strength is built to predict the residual ultimate strength of cracked stiffened plate under extreme cyclic loads.