Stochastic response and seismic reliability analysis for underground structures

In this paper, a new approach for the dynamic reliability assessment of finite element modelled underground structures under earthquake excitations is proposed. The approach is established based on the thoughts of the newly developed probability density evolution method, which is capable of capturing the instantaneous probability density function (PDF) and its evolution of the responses of nonlinear stochastic structures. Associated with the effective stress method and the finite element method, the instantaneous probability density and the evolution process for the seismic response of underground structures can be studied effectively. The first-passage reliability problem is investigated from the level-crossing process to analyze the reliability of underground structures under seismic excitations. Using the proposed method, numerical example of underground pipeline is investigated. The examples show that the proposed method is of high application in analyzing the reliability of underground pipeline.