地铁隧道二次衬砌钢筋网防裂性能研究  

Research on crack prevention performance of reinforced mesh in the secondary lining of subway mountainous tunnel

作　　者：李强 郑国平 Li Qiang;Zheng Guoping

机构地区：[1]杭州市地铁集团有限责任公司

出　　处：《现代城市轨道交通》2020年第1期44-49,共6页Modern Urban Transit

基　　金：浙江省交通运输厅科研计划项目资助——隧道结构补偿收缩无缝施工及钢筋网综合防裂技术研究(2015J05)

摘　　要：为了定量分析防裂钢筋网提高隧道衬砌结构抗裂性能的机理和幅度,以地铁双线隧道二次衬砌结构为研究对象,采用荷载结构法和杆系有限元数值模拟方案,定量分析二次衬砌结构不设置与设置钢筋网这2种情况下的开裂临界荷载。其中素混凝土结构以达到极限拉应变为临界状态,衬砌结构增设钢筋网后以达到GB 50157-2013《地铁设计规范》允许的最大裂缝宽度0.2mm为临界状态。分析结果表明,配置防裂钢筋网后,Ⅲ级和Ⅳ级围岩衬砌结构抗裂性能可分别提高22.4%和19.3%,Ⅴ级围岩衬砌结构抗裂性能提高15.2%;Ⅲ级和Ⅳ级围岩二次衬砌结构的破坏形式由脆性破坏变为延性破坏,从而提高了其安全性能。In order to quantitatively analyze the mechanism and range of improving cracking prevention performance of tunnel lining structure by using cracking prevention steel mesh,taking the secondary lining structure of double track tunnel as a research object,using the load structure method and the bar system finite element numerical simulation scheme,quantitatively analyzes the critical cracking load of the secondary lining structure without setting or with setting the steel mesh.The critical state of plain concrete structure is to reach the ultimate tensile strain,and the critical state of the lining structure is to reach the maximum crack width of 0.2 mm allowed by GB 50157-2013 for metro design.The results show that the crack resistance of class III and class IV surrounding rock lining structure is improved by 22.4%and 19.3%respectively,and that of class V surrounding rock lining structure is improved by 15.2%.The failure mode of class III and class IV surrounding rock secondary lining structure changes from brittle failure to yielding failure,thus improving its safety performance.

关 键 词：地铁 隧道 二次衬砌 钢筋网 荷载结构法 杆系有限元数值法 防裂机理 

分 类 号：U456.2[建筑科学—桥梁与隧道工程]