Seismic Vulnerability Analysis of Aqueducts Based on Probability Density Evolution Method

Aqueduct structures require high seismic performance, underscoring the critical importance of seismic vulnerability analysis. Previous studies have utilized traditional boundary methods, Copula methods, incremental dynamic analysis, or logarithmic normal cumulative distribution functions for vulnerability analysis. Currently, most existing research methods suffer from excessive computational complexity, limited flexibility, and reduced stability. To address these limitations, this study introduces a seismic vulnerability analysis approach for culvert structures that utilizes probability density evolution. The study performed a seismic vulnerability analysis on a three-span simply supported culvert structure, from the middle route of the South-to-North Water Diversion Project in China, and developed a fiber model using OpenSees finite element software for nonlinear time history response analysis. The research produced the vulnerability curve of the culvert structure, concluding that: 1) seismic vulnerability analysis based on probability density evolution effectively determines the structure’s failure probability and vulnerability curve; 2) failure probability distributions and trends vary for piers and supports under different seismic intensities, with supports failing more quickly; and 3) supports in culverts exhibit higher failure rates compared with piers under similar conditions, with probabilities of 6.528%, 28.346%, 35.203%, and 17.872% higher, depending on the type of pier with which it is being compared.