The Seismic Safety Analysis Of Xianyou Pumped Storage Power Station Lower Reservoir Faced Rockfill Dam On The Low Water Level Condition

As our country supports the development of water conservancy vigorously and plays the advantage of water resources,the concrete-faced rockfill dams built in the high-intensity earthquake region increase year by year,especially in the western region.Therefore,it is very important to study the dynamic characteristics and seismic safety analysis of concrete faced rockfill dam.Recently,the dynamic analysis of concrete faced rockfill dam is mostly aimed at the full storage period,and the dynamic analysis of the low water level is relatively few.However,under the condition of low water level,the possibility of sliding of the upstream dam slope is relatively large.In this paper,a three-dimensional finite element static and dynamic calculation program based on the Xianyou Pumped Storage Power Station Lower Reservoir Faced Rockfill Dam has been developed,which can be used to calculate the dynamic response of concrete faced rockfill dam and the stability of dam slope.The obtained results can provide suggestions for the seismic design and construction of the same type and same grade rockfill dam.The main contents are as follows:(1)The basic principle of finite element and the discrete mathematical model of concrete faced rockfill dam are introduced.In addition,the calculation method of the static and dynamic nonlinear equations of the concrete faced rockfill dam is elaborated in detail,and the corresponding finite element calculation program is developed.(2)The three-dimensional finite element model of CFRD is established and the dead water level dropped from the normal water level by steps unload is taken as calculation condition.The stress and deformation of the rockfill and the panel are calculated by the finite element static program,which provides the basis for the dynamic calculation of the dead water level.(3)Three-dimensional dam dynamic calculation is carried out to study the dynamic calculation results of the finite element of the dam and the panel.Then,the dynamic response and distribution law of the displacement of the dam,the panel and the joint are obtained.Meanwhile,seismic stability analysis of dam slope and concrete face slab is performed.(4)The results of calculating the residual deformation of rockfill summarized by Shen Zhujiang academician et al is adopted to calculate the stress and deformation of the slab and the joint and the permanent deformation of the rockfill.According to the results of the calculation,the Xianyou Pumped Storage Power Station Lower Reservoir Faced Rockfill Dam is stable and safe in the dead water level check earthquake conditions.