多因素作用下含连拱隧道边坡地震动力响应特性研究  

Seismic dynamic response characteristics of slope with double-arch tunnel under multiple factors

作　　者：江学良[1,2] 张继琪 杨慧[1,2] 赵富发 范文臣 JIANG Xue-liang;ZHANG Ji-qi;YANG Hui;ZHAO Fu-fa;FAN Wen-chen(School of Civil Engineering,Central South University of Forestry and Technology,Changsha 410004,China;Institute of Geotechnical Engineering,Central South University of Forestry and Technology,Changsha 410004,China)

机构地区：[1]中南林业科技大学土木工程学院,湖南长沙410004 [2]中南林业科技大学岩土工程研究所,湖南长沙410004

出　　处：《振动工程学报》2020年第6期1291-1301,共11页Journal of Vibration Engineering

基　　金：国家自然科学基金资助项目(51204125,51404309,31971727);湖南省自然科学基金资助项目(2018JJ3882,2020JJ4944)。

摘　　要：为了研究含连拱隧道边坡地震动力响应特性,设计了一个几何相似比为1∶20的含连拱隧道软弱围岩边坡,并完成了振动台试验。以峰值为0.4g的汶川(WC)波、Kobe波和EL-Centro波(EL波)为激振波,探究了地震波类型和激振方向等多因素作用下含连拱隧道边坡地震动力响应特性。研究表明:(1)随着地震波类型、激振方向、测点位置等因素的变化,边坡加速度放大系数表现出明显的非线性放大趋势。(2)在地震波水平(X)向激振下边坡岩体主要产生水平向的地震响应,在竖直(Z)向激振下边坡岩体主要在竖直向产生地震响应;在双向(XZ)地震波激振下,加速度响应整体上由大到小依次是K-XZ>WC-XZ>EL-XZ。(3)竖直加速度放大系数在岩体分界面处汶川波与Kobe波、EL波产生不同的变化趋势。(4)整体上,地震波双向激振下边坡的动位移响应幅度依次是ELXZ>WC-XZ>K-XZ,单向激振相对于双向激振动位移响应幅度较弱。(5)在地震波双向激振下,边坡岩体分界面处加速度响应较大,岩体容易被破坏,建议在实际工程中提前进行加固处理。In order to study the seismic dynamic response characteristics of the slope with double-arch tunnel,a large-scale shaking table model test of the slope with multi-arch tunnel whose scale is 1∶20 is designed and finished.A series of tests is performed with different excitation direction seismic waves including Wenchuan(WC),Kobe and EL-Centro(EL)seismic waves whose peaks are 0.4 g.The influence of multiple factors including seismic wave type and excitation direction on the dynamic response of the slope with double-arch tunnel is discussed.The results show that:(1)The dynamic response of the seismic acceleration presents obvious nonlinear amplification trend with change of seismic waveform,excitation direction and the location of transducers.(2)Under the unidirectional seismic wave excitation in the X or Z direction,the dynamic response of the rock slope mainly occurs along the same direction of inputted seismic wave.The order of the acceleration seismic response amplitude of slope under the coupled excitation of horizontal and vertical(XZ)direction is K-XZ>WC-XZ>EL-XZ.(3)The three kinds of seismic waves have different trends at the boundary of rock strata.(4)As a whole,the order of seismic displacement response amplitude of the rock slope is EL-XZ>WC-XZ>K-XZunder the bidirectional seismic wave excitation,and the seismic displacement response under the bidirectional excitation is stronger than that under the unidirectional excitation.(5)The position near the separatrix of the rock strata is easy to generate a shear failure under the coupled excitation.In practical engineering,some measures of pre reinforcement processing should be taken.

关 键 词：地震工程 地震动力响应特性 振动台试验 加速度响应 动位移响应 

分 类 号：TU435[建筑科学—岩土工程] TH825[建筑科学—土工工程]