Seismic response of a concrete-faced rockfill dam to near-fault pulse-like ground motions

An increasing number of high rockfill dams are constructed and planned in the western region, and most of them are situated near the seismic fracture belt. With the increase of high dams, the probability of encountering near-field earthquake is increased, and the seismic response of dams to near-field ground motions should be studied urgently. In this paper, ten near-fault ground motions are selected from Jiji Earthquake occurred in Taiwan, and the numerical results of the dam under two types(pulse-like and non-pule) of earthquake records are compared, including acceleration, horizontal displacement of the rockfill and lop-direction tensile stress of the concrete face slab of concrete-faced rockfill dam(CFRD). It is pointed out that horizontal displacement of the rockfill and lop-direction tensile stresses to pulse-like near-fault ground motions are significantly greater than that to non-pulse ground motions. Meanwhile, pulse-like effect grow along with the increase of PGV/PGA(peak ground velocity/peak ground acceleration). Therefore, the special research should be done on the seismic response of a concrete-faced rockfill dam to pule-like ground motions. It is necessary to evaluate comprehensively the security and ultimate aseismic capacity of rockfill dams. © 2017, China Water Power Press. All right reserved.