【作者】 杨光；

【导师】 侯艳娟；

【作者基本信息】 北京交通大学 ， 土木工程， 2017， 硕士

【摘要】 随着我国经济社会的持续快速发展,我国城镇化进程的加快推进,各大城市都已开通运营地下轨道交通系统,不少中型城市也已将建设轨道交通列入发展规划。然而在城市轨道交通系统服务区域经济发展、提高生活品质的同时,频繁发生的地铁隧道施工事故也一次又一次给社会经济造成严重损失,威胁到了社会公众的安全,动摇公众对地下轨道交通系统的期待和信心。城市地层中埋藏着许多管线,地铁隧道施工会不可避免地引起周围地层的扰动,导致埋设在地层中的管线发生变形甚至破坏。对于地下管线,在隧道施工之前及施工过程当中如何准确预测这些管线的变形规律及变形量、准确判断管线状态对于施工安全至关重要;对于隧道施工,如何准确判断地下管线的渗漏水对地层造成的影响、预测管线渗漏造成的地层影响范围,进而提高隧道施工安全性。针对这些问题,本文主要工作及研究成果如下:1.利用Midas-NX数值模拟软件以及FLAC3D有限差分软件,根据隧道与地下管线的三种空间位置关系(管-隧垂直、管-隧平行、管-隧斜交),研究了在不同空间位置关系的情况下隧道施工对地下管线的影响规律,得出了隧道以0°角穿越地下管线为最有利穿越角度的结论。2.利用Midas-NX数值模拟软件以及FLAC3D有限差分软件,研究了与地下管线沉降变形相关的因素,如管线材质、管线强度、衬砌强度、管-隧间距、管-隧夹角、刀盘推力等因素的影响规律。3.利用Geo-Studio渗流分析软件,研究了地下管线在隧道施工扰动发生渗漏水的情况下,管线内压力、管-隧相对位置以及管线破裂程度这三个因素对渗漏水在地层中产生渗流场的影响规律。4.以京广桥地铁隧道施工事故案例为背景,综合利用Geo-Studio、Midas-NX以及FLAC3D软件对事故演化过程进行了全过程数值模拟分析,结果显示该事故的发展演化过程为存在初始渗漏的污水管线在隧道施工扰动下发生变形破坏而最终导致隧道涌水以及地层塌陷,地下管线渗漏水是影响隧道施工安全的重要因素。更多还原

【Abstract】 With the sustained and rapid development of China’s economy and society,with the accelerated process of urbanization in China,the major cities have already opened operations underground rail transit system,many medium-sized cities have also included the construction of rail transportation in the development plan.However,while the urban rail transit system is making contributions to the economic development,and improving the quality of life at the same time,the frequent occurrence of subway tunnel construction accidents caused social and economic losses again and again,which not only seriously threat public safety but also shake the public expection and confidence on the underground rail transit system.There are many pipelines buried in the urban strata,and subway tunnel construction will inevitably cause disturbance of the surrounding strata,resulting in deformation or even damage to the pipeline.For underground pipelines,how to accurately predict the deformation law and deformation value of these pipelines before and during the construction of the tunnel,how to accurately determine the pipeline status is critical to the construction safety.For the tunnel construction,how to accurately determine the impact of underground water leakage on the formation,how to predict the scope of the impact caused by the pipeline leakage on the formation is also very important.In view of these problems,this paper has made the following research results:1.By means of the numerical simulation software Midas-NX and the finite difference software FLAC3D,in terms of three spatial positions between pipeline and tunnel(pipe-tunnel vertical,pipe-tunnel parallel,pipe-tunnel oblique),the influence of tunnel construction on underground pipelines under different spatial position relations is studied,concluded that the tunnel passes through the underground pipeline at the angle of 0° is the most favorable crossing angle.2.By means of the numerical simulation software Midas-NX and the finite difference software FLAC3D,the factors related to the settlement and deformation of underground pipeline are studied,such as pipeline material,pipeline strength,lining strength,pipe-tunnel spacing,pipe-tunnel angle,cutter thrust and other factors.3.By means of the seepage analysis software Geo-Studio,the influence of the pressure in the pipeline,the relative position of the pipe-tunnel and the degree of fracture of the pipeline on the seepage in unsaturated soil were studied.4.To Jing Guangqiao subway tunnel construction accident as a real case,the whole process of numerical simulation is carried out.The simulation results show that the evolution of the accident is that the sewage pipeline had initial leakage,the water weakened the ground,then the tunnel construction disturbance caused the deformation and damage of sewage pipeline,and eventually lead to formation subsidence and tunnel gushing.更多还原