上穿既有地铁的综合管廊三维地震响应研究

Research on the Three-dimension Seismic Dynamic Response of Integrated Pipe Gallery above-crossing Existing Subway

以北京城市副中心城市综合管廊工程为背景,基于有限元理论,采用ANSYS程序建立上穿既有地铁的综合管廊计算模型,分析在EL Centro波作用下引起的动力数值响应特征。研究表明:(1)沿垂直管廊水平走向输入地震波,引起的最大水平及竖向位移分别为0.073 m和0.033 m;而竖向输入地震波只引起竖向位移,最大值为0.145 m;双向(垂直管廊水平走向和竖向)同时输入地震波引起水平的位移响应与单独水平方向输入有明显的差别,而产生竖向位移与单独竖向输入有良好的一致性。(2)双向输入地震波引起管廊在水平和竖向的加速度峰值分别为0.886g、0.819g,明显大于单向输入引起的加速度响应(0.52g、0.75g)。(3)结构的应力峰值主要在第2~5s持续波动,双向输入产生的Mises应力峰值为2.46 MPa,远大于单方向地震输入产生的Mises应力(0.92 MPa、0.71 MPa)。

Taking the integrated pipe gallery project of Beijing City Sub-center City as the background,a utility pipe gallery above-crossing existing subway was modeled by ANSYS based on the finite element theory.The dynamic numerical response characteristics caused by the EL Centro wave were analyzed in the program.The research shows that:(1)The maximum horizontal and vertical displacements caused by the input seismic waves along the horizontal direction of the vertical pipe gallery are 0.073 m and 0.033 m respectively;while the vertical input only causes vertical displacement,and the maximum value is 0.145 m;the two-way(the horizontal direction of the vertical gallery and vertical direction)input seismic waves generate horizontal displacement response to be significantly different from separate horizontal input,and vertical displacement is in good accord with individual vertical input.(2)The two-way input seismic waves cause the acceleration peaks of the pipe gallery in horizontal and vertical directions to be 0.886 g and 0.819 g respectively,which is clearly larger than the acceleration response(0.52 g,0.75 g)caused by one-way input.(3)The stress peak of the structure mainly fluctuates continuously in the 2~5 s,and the peak of the Mises stress generated by the bidirectional input is 2.46 MPa,which is much larger than the Mises stress(0.92 MPa,0.71 MPa)generated by the unidirectional seismic input.