Reliability-based Sensitivity Analysis of Mechanical Components with Strength and Stiffness Failure Based on Copula Function

A reliability and reliability-based sensitivity analysis on mechanical components with the strength and stiffness failure is carried out in the proposed paper. Due to the unknown distributions of random variables, the fourth moment method and the perturbation theory are utilized to calculate the reliability of each failure mode. Based on the theory of probability and copula theory, the reliability with multiple failure modes are then obtained based on the built joint distribution function with selected copula function. Reliability sensitivity refers to the partial derivative of the reliability with respect to basic random variables. According to the matrix differential method, the parameters sensitivity analysis is carried out and the results obtained could be a guide to optimization design. The proposed method is proved to be practical by the numerical example.