软土地层地铁盾构隧道结构病害数值模拟及分析  

Numerical Modeling Analysis of Structural Defects of Shield Tunnel in Soft Soil Area

作　　者：李庆桐 LI Qingtong(Shanghai Shentong Metro Group Co.,Ltd.,Shanghai 201103,China)

机构地区：[1]上海申通地铁集团有限公司,上海201103

出　　处：《铁道标准设计》2021年第1期95-103,共9页Railway Standard Design

基　　金：国家自然科学基金项目(51778474)。

摘　　要：地铁盾构隧道在服役过程中,其衬砌结构表面难以避免地存在不同严重程度的结构病害,如裂缝和渗漏水。为了能够客观地评定结构病害的严重程度,迫切需要研究结构病害主要参数与结构服役性能之间的力学关系。以地铁盾构隧道衬砌结构表面的裂缝和渗漏水病害为研究对象,基于地层结构法,采用接头弱化的盾构隧道三维实体有限元模型,建立可以同时模拟裂缝和渗漏水两种结构病害的三维实体有限元模型,揭示裂缝和渗漏水病害共同存在情况下衬砌结构服役性能的变化规律。研究表明:随着裂缝病害长度、宽度和渗漏水病害渗透系数等参数大小的单调递增,裂尖最大应力均呈现出单调增大的趋势;十字缝处发生渗漏时的裂尖最大应力最大,其次是纵缝处,最小的是环缝处;病害参数对裂尖最大应力影响的主次顺序为裂缝宽度、裂缝长度、渗漏水渗透系数、渗漏水位置。During the course of service,metro shield tunnel inevitably has some structural defects of different severities,such as cracks and water leakage.In order to evaluate the severities of structural defects objectively,it is urgent to study the mechanical relationship between the main parameters of structural defects and the service performances of structures.This paper takes cracks and water leakage on the lining surface of metro tunnel as the study objects,and adopts three-dimensional solid finite element model(FEM)of shield tunnel based on layer structure method.The FEM of joint-weakening is established to simulate cracks and water leakage simultaneously and reveal the variation law of lining structure service performance in case of the coexistence of cracks and water leakage.The results show that with the monotone increase of crack length,width and permeability coefficient of water leakage,the maximum stress of crack tip increases monotonously.When water leakage occurs at the cross joint,the maximum stress of crack tip is the largest,followed by the longitudinal joint,and the smallest is at the circular joint.The order of principal factors affecting the maximum stress of crack tip are crack width,crack length,permeability coefficient and position of water leakage.

关 键 词：地铁 盾构隧道 衬砌结构 裂缝病害 渗漏水病害 数值模拟 软土地层 

分 类 号：U457.2[建筑科学—桥梁与隧道工程] U445.43[交通运输工程—道路与铁道工程]