含子盆地的二维沉积盆地非线性地震反应分析  

Nonlinear seismic response analysis of two-dimensional sedimentary basin with sub-basin

作　　者：陈树培 温卫平[1,2] 翟长海[1,2] 白克生 CHEN Shupei;WEN Weiping;ZHAI Changhai;BAI Kesheng(Key Laboratory of Structures Dynamic Behavior and Control of the Ministry of Education,Harbin Institute of Technology,Harbin 150090,China;Key Laboratory of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information Technology,Harbin Institute of Technology,Harbin 150090,China)

机构地区：[1]哈尔滨工业大学结构工程灾变与控制教育部重点实验室,黑龙江哈尔滨150090 [2]哈尔滨工业大学土木工程智能防灾减灾工业与信息化部重点实验室,黑龙江哈尔滨150090

出　　处：《世界地震工程》2023年第4期66-76,共11页World Earthquake Engineering

基　　金：国家自然科学基金(U1939210,52178469)。

摘　　要：在沉积盆地中,由于地表河流和湖泊等的长期沉积作用,容易在盆地内形成新的沉积盆地,称为子盆地。子盆地土体物理性质和周围土体有显著差别,因此子盆地的存在会对整个盆地的地震响应产生显著的影响。本文基于ABAQUS有限元计算平台,以理想二维梯形沉积盆地为例,针对盆地-子盆地这一特殊场地,重点分析了盆地尺寸、盆地-子盆地相对位置、子盆地介质波速和外围盆地倾角等影响因素对盆地-子盆地地震反应的影响。结果表明:子盆地的存在显著影响了盆地内的地震动,子盆地位于盆地中央区域时,对地震动的放大效果最为显著,PGA最大可被放大2倍左右;此外,子盆地介质波速越小,对盆地地震反应的影响最显著,但子盆地介质波速的变化对远离子盆地区域的地震动影响不明显;随外围盆地边缘倾角的增大,子盆地区域PGA幅值随之减小并向左移动,沉积盆地中央区域PGA幅值也随之减小。Within the sedimentary basins,it is easy to form new sedimentary due to the long-term sedimentation of rivers and lakes,which is widely known as sub-basin.The soil physical properties of the sub-basin are very different from the surrounding soil,so the existence of sub-basin would have a significant impact on the seismic response of the whole basin.Based on the ABAQUS finite element calculation platform,this paper studied the earthquake response of basin-and-sub basin model.The basin shape was assumed as an ideal two-dimensional trapezoidal.The influence of basin size,basin-sub-basin relative position,shear wave velocity of sub-basin medium and peripheral basin dip angle on the basin-and-sub basin seismic response was analyzed.The results show that the presence of sub-basins significantly affects the ground motion within the basin.When the sub-basins were in the central area of the basin,the amplification effect of ground motion is the most significant,and the maximum amplification of PGA can be about 2 times with respect to the no-sub basin model.In addition,the smaller the shear wave velocity of sub-basin medium,the most significant effect on the basin seismic response,but the change of the shear wave velocity of sub-basin medium has no obvious effect on the ground motion far away from the sub-basin.With the increase of the marginal dip angle of the peripheral basin,the PGA amplitude of the sub-basin decreases and moves to the left,and the PGA amplitude of the central area of sedimentary basin also decreases.

关 键 词：盆地效应 子盆地 地震反应 有限元数值模型 

分 类 号：TU435[建筑科学—岩土工程]