浅埋衬砌隧道-邻近建筑地震动力相互作用IBEM模拟

采用高精度间接边界元方法(IBEM)考察地震波入射下隧道-邻近建筑物二维地震动力相互作用的规律。结果表明:建筑物与邻近隧道存在着明显的相互作用,整体动力反应规律取决于隧道,建筑物之间的空间位置关系、隧道埋深、入射波的频率和角度等因素。隧道位于建筑物正下方时,刚性衬砌隧道(相对围岩)对上部结构主要表现为隔震效应;隧道位于建筑物两侧时,隧道对建筑顶部位移有明显放大效应,最大可放大约40%。同时隧道应力也明显增大,最大可放大约43%。因此实际中需根据隧道-建筑物的空间位置关系,适当调整衬砌隧道与沿线建筑物的抗震设防水平。

IBEM Simulation of Seismic Dynamic Interaction between a Lined Tunnel and-Adjacent Buildings

A high-precision indirect boundary element method (IBEM) is adopted to investigate the seismic response characteristics and the interaction laws between a tunnel and its adjacent buildings under seismic wave incidence. The results show that there is a distinct interaction between the buildings and the adjacent subway tunnel. The whole dynamic response depends on the spatial location of tunnels and buildings, the buried depth of tunnel, the frequency and the angle of incident wave, etc. The isolation effect is obvious when the rigid lined tunnel is just below the building. The displacement at the ground surface and the top of the building amplifies obviously when the tunnel is located on either side of the building, and the maximum amplification can reach 40%. Moreover, the stress in the tunnel lining also amplifies when the tunnel is located at either side of the building, and the maximum amplification is about 43%. In practice, it is necessary to adjust the seismic fortification levels of lined tunnels and the buildings along the tunnels according to their spatial location.