Seismic performance evaluation of high CFRD slopes subjected to near-fault ground motions based on generalized probability density evolution method

Abstract

This research mainly addresses evaluating the seismic reliability and analyzing the random dynamic response of high concrete-faced rockfill dam (CFRD) slopes suffering from the near-fault earthquakes by establishing a novel method of generating the representative acceleration time histories coupled with the recently proposed generalized probability density evolution method (GPDEM). A probability evaluation is performed after generating two groups of near-fault ground motions, pulse-like and non-pulse-like earthquakes, coupling a series of statistical stochastic parameters with the spectral representation-random function method. A 242-m-high CFRD is selected as an example for finite element stochastic dynamic time series analysis, and second-order statistical values (including mean and standard deviation) and probability information of three indices the safety factor, the cumulative time of safety factor ≤ 1.0 (Fs ≤ 1.0) and the maximum cumulative slippage of the dam slopes are determined, respectively. The effective non-stationary near-fault earthquakes will be adopted to determine the stochastic earthquake loading for the dynamic response evaluation of dam slopes. The statistical and probabilistic results demonstrate that the seismic characteristics make a great difference to the seismic response of slope stability as well as the pulse properties. The stochastic near-fault earthquakes combined with the GPDEM can evaluate seismic performance and reliability effectively from the perspective of randomness, and the failure probability can be obtained directly.