破碎板岩隧道两台阶带仰拱一次开挖工法特性研究  

Study on the Continuous Two-bench Excavation Method for Inverts of Tunnels in Broken Slate

作　　者：崔光耀[1] 熊泳 王庆建[2] CUI Guangyao;XIONG Yong;WANG Qingjian(North China University of Technology,Beijing 100144,China;China Railway Tunnel Group,Nanning 530000,China)

机构地区：[1]北方工业大学,北京100144 [2]中铁隧道集团四处有限公司,南宁530000

出　　处：《高速铁路技术》2023年第1期7-12,19,共7页High Speed Railway Technology

基　　金：国家自然科学基金(52178378);昆明铁路局科技项目重点课题(K17G43)。

摘　　要：为保证破碎板岩隧道施工的安全性及稳定性,本文以玉磨铁路立新隧道为研究背景,对破碎板岩隧道的破坏特征和工法特性进行了研究。结果表明:(1)破碎板岩隧道的破坏特征可分为应力重分布作用下的层理破坏、重力作用下的块体滑落、掉块导致的大范围塌方3个阶段;(2)两台阶带仰拱一次开挖工法较传统台阶法拱顶沉降最大值减小10.66%,仰拱隆起最大值减小8.22%;开挖阶段最大水平位移值减小7.92%;(3)两台阶带仰拱一次开挖工法下收敛值较传统台阶法有所减小,控制效果为12.22%;(4)在支护完成时,两台阶带仰拱一次开挖工法较传统台阶法最大主应力、最小主应力、最大剪切应力分别减小14.29%、13.33%、13.17%;(5)破碎板岩隧道中两台阶带仰拱一次开挖工法优于传统台阶法。研究成果可为破碎板岩隧道的安全施工提供参考。In order to ensure the safety and stability of the construction of the tunnels in broken slate,a case study of the Lixin Tunnel of Yuxi-Mohan Railway is made to study the failure characteristics and construction method characteristics for the tunnels in broken slate.The results show that:(1)The failure characteristics of tunnels in broken slate can be divided into three stages:bedding failure under stress redistribution,block sliding under gravity,and large-scale collapse caused by block falling.(2)Compared with the conventional benching method,the maximum settlement of the crown excavated with the continuous two-bench excavation method for inverts is reduced by 10.66%,and the maximum uplift of the invert is reduced by 8.22%,and the maximum horizontal displacement in the excavation stage is reduced by 7.92%.(3)The convergence value of the continuous two-bench excavation method for inverts is reduced compared with the conventional benching method with a control effect of 12.22%.(4)When the support is completed,the maximum principal stress,minimum principal stress,and maximum shear stress of the continuous two-bench excavation method for inverts are reduced by 14.29%,13.33%,and 13.17% respectively compared with those of the conventional benching method.(5)The continuous two-bench excavation method for inverts is superior to the traditional bench cut method in tunnels of broken slate.The research results can provide a reference for the safe construction of tunnels in broken slates.

关 键 词：破碎板岩 两台阶带仰拱一次开挖工法 破坏特征 数值模拟 

分 类 号：U455.4[建筑科学—桥梁与隧道工程]