地震动入射角度对盆地地震响应的影响  

Seismic response analysis of basin site under SV wave with different incident angles

作　　者：李传勋[1] 丁文昌 金丹丹[1] 刘恒[2] LI Chuanxun;DING Wenchang;JIN Dandan;LIU Heng(Faculty of Civil Engineering and Mechanics,Jiangsu University,Zhenjiang,Jiangsu 212013,China;College of Tranportation Science&Engineering,Nanjing Tech University,Nanjing,Jiangsu 210009,China)

机构地区：[1]江苏大学土木工程与力学学院,江苏镇江212013 [2]南京工业大学交通学院,江苏南京210009

出　　处：《江苏大学学报（自然科学版）》2018年第2期199-203,共5页Journal of Jiangsu University：Natural Science Edition

基　　金：国家自然科学基金资助项目(51109092);国家青年基金资助项目(51308292);中国博士后基金资助面上项目(2016M591785);江苏省青年基金资助项目(1721480042);江苏省普通高校研究生科研创新计划项目(SJZZ16_0198)

摘　　要：为了研究不同入射角度地震动作用下盆地地表地震响应,基于ABAQUS软件显式有限元计算平台,针对某一45°坡角的盆地,以狄拉克脉冲作为输入SV波,探讨了地震波倾斜入射角度改变时盆地地表峰值位移(PGD)等的变化特征.结果表明:入射波作用角度由0°,5°,10°,15°,20°,25°,30°依次增加时,盆地地表PGD表现出先增大后减小的趋势;当入射角度为10°时,地表PGD达到最大值,为输入地震波位移幅值的7.69倍,说明若按垂直入射进行地震响应分析所得结果将偏于不安全;较垂直入射情形,地震波倾斜入射时盆地表现出更为显著的边缘效应,边缘PGD最大值约为盆地中心PGD的1.3倍;地震动响应聚焦区域会随入射角度的增大逐渐向盆地右侧偏移.To analyze the ground motion response of basin site under seismic wave with different incident angles,based on computing platform of ABAQUS,the basin model with fixed slope angle of 45°and Dirac pulse as inputting SV wave was established by explicit FE method,and the peak ground displacements(PGD)were obtained.The results show that when the incident angles of input waves are increased in sequence from 0°to 5°,10°,15°,20°,25°and 30°,the surface PGD of basin are increased with latter decreasing.The surface PGD reaches the maximum value when the incident angle is 10°,which is 7.69 times of the amplitude of input seismic wave.The analysis results are partially unsafe if the vertical incidence is considered.Compared with vertical incidence case,the edge effect of basin is more significant under seismic wave with different incident angles,and the maximum value of edge PGD is about 1.3 times of that in the center of basin.The seismic response focus area gradually shifts to the right side of basin when the incident angle is increased.

关 键 词：盆地 地表峰值位移 聚焦效应 斜入射 黏弹性人工边界 

分 类 号：TU435[建筑科学—岩土工程]