地铁站间临近联络线基坑施工过程变形力学特性数值模拟  

Numerical Simulation of Deformation Mechanical Characteristics of Foundation Pit near Connecting Line between Subway Stations during Construction

作　　者：芮勇勤[1] 于晓莎 RUI Yongqin;YU Xiaosha(School of Resources and Civil Engineering,Northeastern University,Shenyang,China,110819)

机构地区：[1]东北大学资源与土木工程学院,辽宁沈阳110819

出　　处：《沈阳建筑大学学报（自然科学版）》2022年第1期33-41,共9页Journal of Shenyang Jianzhu University：Natural Science

基　　金：国家重点研究发展计划(973)项目(2017YFC1503101,2016YFC0801602)。

摘　　要：目的研究既有地铁站造成的土体应力重分布对临近联络线基坑开挖及回填稳定性的影响,并确定基坑及联络线楼板薄弱区域。方法应用Midas GTS^(3D)有限元计算软件建立从地铁站开挖及围护结构施工到联络线回填完成全过程数值模型,并与工程实测值进行对比,分析地铁站存在对联络线基坑施工过程中土体及楼板力学性能及稳定性的影响。结果地铁联络线施工过程中,基坑周围土体位移从上到下依次减小,垂直及侧向位移均在联络线连续墙附近达到最大值,分别为25.7 mm及7.0 mm;楼板应力及挠度在联络墙及车站连接处达到最大值,分别为1.4 MPa和7.5 mm。结论联络线基坑回填完成时,其背向车站连续墙处地表沉降接近规范限值,应作为基坑监测着重关注点;楼板应力及挠度远小于限值,地铁站的存在对联络线工程起有利作用,在一定程度上可提高施工过程中的稳定性。To study the influence of the redistribution of soil stress caused by the existing subway station on the stability of the excavation and backfilling of the adjacent connection line,and determine the weak area of the foundation pit and the connection line floor,the Midas GTS^(3D) finite element calculation software was used to establish a numerical model for the entire process from subway station excavation and construction of the enclosure structure to completion of the backfill of the connecting line,with which the measured value of the project is compared with to analyze the influence of the presence of the subway station on the mechanical properties and stability of soil and floor slab during the construction of the connecting line foundation pit.During the construction of the subway connecting line,soil around the foundation pit displacement decreases sequentially from top to bottom.The vertical and lateral displacements both reach the maximum near the continuous wall of the connecting line,which are 25.7 mm and 7.0 mm respectively.The stress and deflection of the floor slab reach the maximum at the connection between the connecting wall and the station,respectively 1.4 MPa and 7.5 mm.When the backfilling of the foundation pit of the tie line is completed,the surface settlement at the back of the diaphragm wall of the station is close to the specification limit.Analyzing the existence of subway stations has a beneficial effect on the construction of the connecting line,and it can improve the stability during the construction process to a certain degree.

关 键 词：地铁车站 基坑开挖 联络线施工 基坑监测 数值模拟 

分 类 号：TU391[建筑科学—结构工程]