考虑土体非线性山-谷耦合复杂场地空间相关多点地震动模拟  

Simulation of the spatially correlated multi-point ground motions of the coupled alluvial valley-hill terrain considering the soil nonlinearity

作　　者：何颖 尹奔驰 刘中宪 丁晓凡 HE Ying;YIN Benchi;LIU Zhongxian;DING Xiaofan(School of Civil Engineering,Tianjin Chengjian University,Tianjin 300384,China;Tianjin Key Laboratory of Civil Structure Protection and Reinforcement,Tianjin 300384,China)

机构地区：[1]天津城建大学土木工程学院,天津300384 [2]天津市土木建筑结构防护与加固重点实验室,天津300384

出　　处：《振动与冲击》2024年第16期118-128,158,共12页Journal of Vibration and Shock

基　　金：国家自然科学基金联合基金重点支持项目(U2139208);国家自然科学基金(51908401)。

摘　　要：采用考虑局部场地非线性地震波散射效应的空间相关多点地震动模拟方法,对山-谷耦合场地的地震动进行定量模拟分析。非线性地震波散射效应基于有限元-间接边界元耦合法和等效线性土体模型进行计算。结果表明,山体的存在会增大沉积内的地震动反应,对短周期的地震波的放大效应更为显著,增幅可达50%。相较于单一沉积谷地地形的沉积谷地外部,山-谷耦合场地中山体地震响应有所减小。相比线性模型,考虑土体非线性时,沉积谷地地震动强度较线性时的结果有所降低,反应谱峰值位置也会发生改变,但山体影响更为显著。不同山体形状对谷地影响不同,对于谷地内部分点位影响的差别可达40%。该研究为山-谷耦合场地工程结构抗震设防提供了部分理论依据和计算方法。A spatially correlated multi-point ground motion simulation method considering the nonlinear scattering effect of seismic waves in local site is adopted.The ground motion simulation of mountain-valley coupling site is quantitatively compared and analyzed.Based on the coupled finite element-indirect boundary element method(FEM-IBEM)and the equivalent linear soil model,the nonlinear scattering effect of seismic waves is calculated.The results show that:The presence of mountains will increase the ground motion response in sediments,and the amplification effect on short period seismic waves is more significant,with an increase of up to 50%.Compared to the outside of a single sedimentary valley terrain,the seismic response on the mountain with basin-mountain coupled terrain is reduced.When considering the nonlinearity of the soil,the ground motion intensity of the sedimentary valley is lower than that of the linear model.The peak position of the response spectrum will also change.However,the impact of mountains is more significant.Different mountains have different influences on the valley,the difference in impact on some points within the valley can reach 40%.The research provides some theoretical basis and calculation methods for the seismic fortification of engineering structures in mountain-valley coupled sites.

关 键 词：地震动模拟 等效线性化 局部场地效应 有限元-边界元耦合法 山-谷耦合场地 

分 类 号：TU435[建筑科学—岩土工程] P315.9[建筑科学—土工工程]