两河口超高心墙堆石坝三维非线性地震反应分析

Three dimensional nonlinear seismic response analysis of Lianghekou super high core rockfill dam

中国水能资源主要集中在西部地区,西部地区属于地震强震区,高土石坝的抗震安全是该区域水电开发最突出的问题之一。基于《水电工程水工建筑物抗震设计规范》(NB 35047—2015)的有关规定,采用设定地震场地相关设计反应谱生成的地震动时程对两河口超高心墙堆石坝进行三维非线性地震反应分析。结果表明:位于V形河谷中的两河口超高心墙堆石坝坝体加速度在4/5坝高以上;1/3坝轴线长度范围内的河谷中部放大效应显著,表现出明显的“鞭梢效应”和三维河谷效应。在此基础上提出了两河口超高心墙堆石坝的抗震加固范围。

China's hydropower resources mainly concentrated in west China,which is also the meizoseismal area of China.The seismic safety of high earth rockfill dams in these areas is one of the most serious problems in China's hydropower development.Based on the relevant provisions of Code for seismic design of hydraulic structures of hydropower project(NB 35047—2015),the three-dimensional nonlinear seismic response analysis of Lianghekou super high core rockfill dam was carried out by using the ground motion time history generated by site related design response spectrum of the scenario earthquake.The research results show that the dam acceleration amplification effect was quite significant in the middle part of the valley which is exactly of 4/5 dam height above and within 1/3 dam axis length for Lianghekou super high core rockfill dam located in a V-shaped Valley.It showed obvious whiplash effect and three-dimensional valley effect.On this basis,the reinforcement range of Lianghekou super high core rockfill dam was proposed.