A Novel Time-Variant Reliability Analysis Method Based on Failure Processes Decomposition for Dynamic Uncertain Structures

Due to the uncertain and dynamic parameters from design, manufacturing and working conditions, many engineering structures usually show uncertain and dynamic properties. This paper proposes a novel time-variant reliability analysis method using failure processes decomposition to transform the time-variant reliability problems to the time-invariant ones for dynamic uncertain structures. The transformation is achieved via two-stage failure processes decomposition. The limit state function with high dimensional input variables and high order temporal parameters is first transformed to a quadratic function of time based on the optimized time point in the first stage of failure processes decomposition. Based on the characteristics of the quadratic function and reliability criterion, the time-variant reliability problem is then transformed to a time-invariant system reliability problem in the second stage. The kernel density estimation method is finally employed for the system reliability evaluation. Several examples are used to testify the effectiveness of the proposed method both in computational efficiency and accuracy.