开展砂质粉土层中矩形截面隧道的动力离心模型试验研究,共进行3组试验,包括土体自由场试验、浅埋隧道试验以及深埋隧道试验,得到土体和隧道结构的地震反应规律,包括不同深度的土体地震反应加速度、土体水平地震反应位移、地表沉降以及隧道横截面方向的动应变。对比几组试验结果,研究隧道的存在对场地地震反应的影响,并探讨不同埋深隧道地震响应的差别。研究结果表明:隧道的4个角点位置地震变形最大,隧道的存在改变了场地的动力特性,深埋隧道的地震响应大于浅埋隧道。
Dynamic centrifuge tests of seismic response of rectangular tunnels in sandy silt are performed. Three experiments are conducted,including free-field test,shallow tunnel test and deep tunnel test. Dynamic behaviour of the soil and tunnel is presented,including soil acceleration at different depths,soil displacement in the horizontal direction,settlement of the ground surface and dynamic strain of tunnels in the transverse direction. Effect of the presence of tunnel on site earthquake response as well as the difference of seismic response of tunnels at different buried depths are analyzed through contrasting the three sets of experimental data. It is concluded that the maximal seismic deformation occurs at four corners of the tunnel,presence of the tunnel changes the dynamic property of site,and seismic response of the deep tunnel is larger than that of the shallow one.