隧道爬坡开挖与水平开挖掌子面稳定性对比分析  

Contrastive Analysis of Working Face Stability in Cases of Climbing Excavation and Horizontal Excavation

作　　者：赵智涛[1,2] 曹伍富 王霆[1,2] ZHAO Zhitao;CAO Wufu;WANG Ting(Beijing MTR Construction Administration Corporation,Beijing 100037;Key Laboratory of Fully Automatic Operation and Safety Monitoring for Urban Rail Transit,Beijing 100037)

机构地区：[1]北京市轨道交通建设管理有限公司,北京100037 [2]城市轨道交通全自动运行系统与安全监控北京市重点实验室,北京100037

出　　处：《现代隧道技术》2018年第6期94-100,共7页Modern Tunnelling Technology

基　　金：轨道交通工程建设安全风险管控标准化研究(SCJJ2018001)

摘　　要：地铁附属结构施工时受场地及工期影响往往采取爬坡开挖方式。为了确定其掌子面的安全状态,文章通过理论分析并结合数值模拟,对比分析了爬坡开挖与水平开挖下掌子面的稳定性。其中,采用极限分析上限法掌子面破坏区假定,对比分析了爬坡开挖与水平开挖的破坏区影响范围及位置;采用数值分析方法,研究了爬坡与水平开挖不同工况下等值应变区的位置和掌子面水平位移变化规律。分析结果表明:隧道爬坡开挖造成的影响区范围略大于水平开挖,影响区位置比水平开挖略低;掌子面0～1/3高度范围内爬坡开挖引起的水平位移比水平开挖略大,掌子面1/3高度以上范围内略小;爬坡与水平开挖下掌子面最大水平位移均位于掌子面1/3高度处,且爬坡开挖下掌子面变形并不大于水平开挖;在不考虑超前支护的情况下,爬坡与水平开挖的掌子面稳定性基本一致,而在选取适宜的超前支护措施前提下,能够保证掌子面的稳定性。Restricted by site and construction period of ancillary structure of metro project,climbing excavation is often adopted.In order to determine tunnel face 's stability,the stabilities of working face in the cases of climbing excavation and horizontal excavation were analyzed by theoretical analysis and numerical simulation.With upperbound limit analysis,the affected scope and positions of failure zone were compared;the position of equivalent strain zone and the law of horizontal displacement changes were studied by simulation analysis.The results show that the scope of failure zone caused by climbing excavation was slightly larger than that by horizontal excavation and the position of affected zone is slightly lower than that by horizontal excavation;the horizontal displacement caused by climbing excavation within a scope of 0-1/3 height of tunnel face is slightly larger than that by horizontal excavation while it is slightly smaller beyond the scope of 0-1/3 height of tunnel face;the maximum horizontal displacements in the cases of climbing and horizontal excavation both occur at the place where is 1/3 height of work face and the deformation of work face in the case of climbing excavation is not larger than that of horizontal excavation;the work face stabilities are mostly the same in the cases of climbing and horizontal excavation without regard to advanced support,and the work face stability is to be guaranteed with proper advanced support.

关 键 词：地铁工程 斜井 掌子面稳定性 极限上限分析 数值模拟 

分 类 号：TU443[建筑科学—岩土工程]