关键词: 非平稳随机地震动模拟, 高心墙坝, 概率密度演化方法, 等价极值, 可靠度分析

Abstract: Seismic reliability evaluation often gives an effective estimate of the dam safety under seismic load. Recently extensive attention has been attracted by the combination of applying artificially simulated stochastic ground motions and quantifying the stochastic responses of structures. Based on Code for Seismic Design of Hydraulic Structures, this paper develops a non-stationary stochastic ground motion model for five different sites using a speactral expression-random function method. Then, we combine this model with a generalized probability density evolution method to extract probability information from dam dynamic responses. Finally, we borrow the idea of equivalent extreme value event, and construct a framework for dynamic reliability analysis of high core wall dams, with dam deformation and dam slope slip used as evaluation indexes. A case study of the Rumei Dam shows that the calculations of dam deformation failure probability are higher than those of the dam slope slip failure. Our analysis framework considers load randomness and gives more accurate failure probability, thus laying a basis for the seismic reliability evaluation of high core wall dams and its application in geotechnical engineering.

Key words: non-stationary stochastic ground motion simulation, high core wall dam, probability density evolution method, equivalent extreme value, reliability analysis