Reliability sensitivity method for non-normal variable

Based on the moment estimation of limit state function for failure probability calculation, a new reliability sensitivity method is presented for limit state function with non-normal variables. The partial differential of the moment of the limit state function to distribution parameters of basic variables is derived. By use of the relationship of the failure probability and the moment of the limit state function, the partial differential of the failure probability to the distribution parameters of basic the non-normal variables is derived, furthermore. Hereby, the reliability sensitivity is obtained for the non-normal variables. Compared with the reliability sensitivity based on the first order and second moment method, a logarithm normal illustration is used to demonstrate the rationality and the precision of the presented reliability sensitivity method. At last, the presented method is employed to analyze the partial differential of the failure probability to the parameters of exponential and Weibull distributions.