Dynamic responses of concrete-faced rockfill dam due to different seismic motion input methods

Abstract

The concrete-faced rockfill dam valley foundation was considered as an open energy system and a reasonable non-uniform seismic motion input method was applied to the dynamic analysis of a concrete-faced rockfill dam based on the generalized plastic model. First, the corresponding program was validated by means of the scattering question of an idealized semicircle valley. Subsequently, the seismic elasto-plastic finite element analyses were performed to compare and investigate the performances of a concrete-faced rockfill dam under different seismic motion input methods. The results show that the dynamic responses of the concrete-faced rockfill dam are decreased by 10%–30% approximately with the use of non-uniform seismic motion input method. As a result, the traditional uniform seismic motion input method would overestimate the responses of the dam. From the perspective of seismic safety evaluation, the overestimations would disturb the reasonable assessment of the aseismic capacity of the dam. Moreover, the slope stability analysis results might be conservative and unreasonable due to overestimating the accelerations during the earthquake.