Sensitivity Analysis for the Stiffened Plate Structure System with Crack Defects

The influence of crack defects on the ultimate strength of stiffened plate is analyzed, and reliability calculation and sensitivity analysis expressions of stiffened plate elements are given in this paper. An approach to sensitivity analysis for the global reliability index are proposed for the structure system which consists of stiffened plate elements with crack defects, providing the base for analyzing the contribution of design variables to the system reliability and seeking conveniently weak elements which reduce the reliability index of structure system. Finally, the validity of the approach is verified by taking a numerical example of a cabin section of the ship structure. The approach proposed in this paper provides an applicable reference for the safe design and maintenance of structure system.