近断层地震动组合斜入射下沥青混凝土面板堆石坝响应研究  

Seismic response of asphalt concrete face rockfill dam under combined oblique incidence of near-fault ground motions

作　　者：许斯年 宋志强[1] 李闯 XU Sinian;SONG Zhiqiang;LI Chuang(State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China,Xi’an University of Technology,Xi’an 710048,China)

机构地区：[1]西安理工大学省部共建西北旱区生态水利国家重点实验室,陕西西安710048

出　　处：《水资源与水工程学报》2024年第4期127-135,共9页Journal of Water Resources and Water Engineering

基　　金：国家自然科学基金重点项目(52039008);陕西省自然科学基础研究计划面上项目(2022JM-276);陕西省教育厅青年创新团队科研计划项目(22JP052)。

摘　　要：西部地区水利工程多建于复杂地震断裂带附近,因此近场地震动的脉冲效应对水工建筑物所产生的影响不可忽略。近断层地震动往往由P波、SV波等共同组成,到达地表后明显带有一定角度,垂直入射假定不再适用,因此有必要开展近断层脉冲型地震动组合斜入射对沥青混凝土面板堆石坝地震响应影响的研究。基于地表二维地震动反演确定P波、SV波斜入射时程,构建近断层地震动组合斜输入模型,选取脉冲型和非脉冲型各5条地震动记录,研究近断层地震动组合斜入射对沥青混凝土面板加速度、应力和坝体永久变形的影响规律。结果表明:与地震动垂直入射相比,面板水平向加速度随P波角度的增大而增大,随SV波角度的增大而减小,竖向加速度及坝体永久变形的规律则相反;面板拉应力随着P波、SV波角度的增大而增大;近断层地震动的脉冲特性对堆石坝的响应有显著放大作用,其中面板拉应力最大增加了116%。Water conservancy projects in the western region of China are mostly built near complex earthquake fault zones,and the pulse-like effect of near-field ground motions on hydraulic structures cannot be ignored.The near-fault ground motion is often composed of P-waves and SV-waves.When the seismic waves reach the surface,they often hit the ground at a certain angle,and the assumption of vertical incidence is no longer applicable.Therefore,it is necessary to clarify the impact of combined oblique incidence of near-fault pulse-like ground motions on the seismic response of asphalt concrete face rockfill dams.Based on the surface two-dimensional seismic motion inversion,the oblique incidence time history of P-waves and SV-waves were obtained,and a combined oblique incidence model of near-fault ground motions was constructed.Five pulse-like and non-pulse-like ground motions were selected to study the influence of the combined oblique incidence of near-fault ground motions on the acceleration,stress,and permanent deformation of asphalt concrete panels.The results show that compared to the vertical incidence of ground motions,the horizontal acceleration of the panel increases with the increase of P-wave angle and decreases with the increase of SV-wave angle,while the vertical acceleration of the panel and permanent deformation of the dam body are on the opposite;the tensile stress of the panel increases with the increase of P-wave and SV-wave angles;the pulse-like characteristics of near-fault ground motions have a significant amplification effect on the seismic response of the dam,with a maximum increase of 116%in panel tensile stress.

关 键 词：沥青混凝土面板堆石坝 近断层地震动 组合斜入射 脉冲效应 地震响应 

分 类 号：TV641.4[水利工程—水利水电工程] TV312