Study on the Ultimate Aseismic Capacity of High Core Rock-Fill Dam

Abstract

Since the 5.12 WenChuan Earthquake occurred in China, evaluation of the ultimate aseismic capacity has been a crucial issue for seismic safety design of high core rock-fill dams. However, reasonable evaluation of the ultimate aseismic capacity of high rock-fill dams still confuses the hydraulic engineers. Thus an original approach to evaluate the ultimate aseismic capacity is proposed. In this approach, the ultimate peak acceleration of input motion which the dam could tolerate is taken as an important index to evaluate the ultimate aseismic capacity. The ultimate peak acceleration can be directly achieved on the basis of 'Specifications for seismic design of hydraulic structures' instead of trial and error method. Then, the proposed method is adopted to evaluate the ultimate aseismic capacity of the 240m ChangHe high rock-fill dam. In addition, comprehensive studies on the dynamic response and potential failure mode as the rock-fill dam subjected to the ultimate tolerable input motion, that is, the rock-fill dam is at verge of failure, are presented. Consequently, the corresponding reinforced design for the high rock-fill dams can be carried out effectively on the basis of the dynamic analysis as the dam reach the ultimate limit equilibrium state.