%0 Journal Article %T 不同场地沉管隧道振动台模型试验研究<br>Research of Shaking Table Model Tests on Immersed Tunnels under Different Conditions %A 程新俊 %A 景立平 %A 崔杰 %A 李永强 %A 董瑞< %A br> %A CHENG Xinjun %A JING Liping %A CUI Jie %A LI Yongqiang %A DONG Rui %J 西南交通大学学报 %D 2017 %R 10.3969/j.issn.0258-2724.2017.06.011 %X 为了研究不同场地条件下沉管隧道的地震反应规律和抗震性能，对干砂、饱和砂土以及水下饱和砂土三种场地条件下沉管隧道体系进行缩尺比为1：30的振动台模型试验.试验结果表明：当输入加速度峰值为0.1g的小震时，三组场地中的土层加速度均保持放大趋势，饱和砂土没有出现液化状态；当输入幅值为0.2g和0.4g时，干砂场地中的土层加速度继续增大，饱和砂土发生液化，表层土体加速度呈现衰减现象；在输入加速度峰值为0.4g时，3组试验的中间管段较端部管段加速度减小百分比最大分别可达11.1%、7.6%和9.4%，柔性接头表现出一定的减震效果；饱和砂土与水下饱和砂土中的土体孔压发展规律基本一致；3组场地中均是隧道底板与中墙角点处的应变较大，是抗震的薄弱部位.<br>：To study the seismic response and anti-seismic behaviour of immersed tunnels at different sites, shaking table tests were conducted in three sets. The reduced-scale ratio of the tests was 130. The site conditions adopted in the tests were dry sand, saturated sand, and saturated sand under an overlying water layer. The experimental results show that when the peak ground acceleration (PGA) of the input excitation is 0.1g, the acceleration amplification factors of dry sand, saturated sand, and saturated sand under an overlying water layer exhibit a magnifying trend. No soil liquefaction occurred in the saturated sand sites. When the input PGAs are 0.2g and 0.4g, the acceleration of the soil deposits of the dry sand site continues to increase, whereas the acceleration of the surface points in the saturated sand sites decreases owing to sand liquefaction. When the input PGA is 0.4g, the maximum reduced acceleration percentages of the middle tunnel elements in the three sets of tests are11.1%, 7.6%, and 9.4%, respectively, compared with those of the end tunnel elements. The flexible joints have a shock absorption effect during the shaking process. The development trends of pore water pressure of the soil deposits correlate well for the saturated sand and saturated sand under an overlying water layer. In addition, the results of the three sets of tests indicate that the nodes between the middle wall and the base slab are the weak positions of the tunnel model %K 沉管隧道 %K 地震反应 %K 振动台试验 %K 接头 %K 上覆水 %K < %K br> %K immersed tunnel %K seismic response %K shaking table test %K joint %K overlying water %U http://manu19.magtech.com.cn/Jweb_xnjd/CN/abstract/abstract12510.shtml