摘要
与远场地震动相比,近断层地震动往往有较大的速度和位移脉冲效应,且由于其发震断层埋深较浅,地震波垂直地表向上入射假定一般不再适用。目前关于水电站厂房抗震研究均未考虑近断层脉冲型地震动斜输入的影响。选取符合某水电站场地条件的近断层脉冲型和非脉冲地震动记录各5条,依据波动理论,采用黏弹性动力人工边界法,推导了SV波三维斜入射下的人工边界等效结点力计算公式,并进行了算例验证。建立了水电站厂房三维塑性损伤有限元分析模型,分析了水电站厂房在脉冲型和非脉冲地震动垂直和斜输入条件下的非线性地震响应。结果表明,近断层脉冲型地震动斜输入可以激起厂房结构的高阶振型,引起水电站厂房下部结构较大的损伤、位移、及应力响应,对厂房的破坏作用最强。
Compared with remote ground motions,near-fault ground motions perhaps have larger velocity and displacement pulse effect.As the buried depth of seismic fault is shallow,the assumption of vertical surface incidence of seismic waves is generally no longer applicable.Until now,the aseismic study on hydropower house has not considered influences of near-fault pulse-type ground motion oblique input.Here,5 near-fault pulse-type ground motion records and 5 near-fault non-pulse type ground motion ones were chosen to meet site conditions of a certain hydropower house and taken as inputs.According to the wave theory,the viscoelastic dynamic artificial boundary method was used to derive calculation formulas of equivalent node forces of artificial boundary under SV wave 3-D oblique incidence.These formulas were verified with examples.A finite element analysis model for 3-D plastic damage of hydropower house was established to analyze its nonlinear seismic responses under vertical and oblique incidences of near-fault pulse-type and non-pulse type ground motions.The results showed that near-fault pulse-type ground motions oblique input can excite high-order modal shapes of a hydropower house structure,cause its lower structure’s larger damage,displacement and stress responses,and have the strongest destructive effect on it.
作者
王飞
宋志强
卢韬
WANG Fei;SONG Zhiqiang;LU Tao(Institute of Water Resources and Hydro-Electric Engineering,Xi’an University of Technology,Xi’an 710048,China;Jiangxi Provincial Water Conservancy Planning Design and Research Institute,Nanchang 330029,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2020年第5期63-73,共11页
Journal of Vibration and Shock
基金
国家自然科学基金(51479165)
陕西省创新人才推进计划-青年科技新星项目(2017KJXX-64)。
关键词
近断层脉冲型地震动
斜入射
水电站厂房
非线性分析
损伤
near-fault pulse-type ground motions
oblique incidence
hydropower house
nonlinear analysis
damage
