摘要
以成渝高速宋家沟一号隧道为工程背景,针对既有隧道原位扩建的三种扩挖方式(变形CRD法、层层剥皮法、三台阶法)的拱顶沉降、围岩收敛、塑性区、围岩竖向应力、初支最小主应力等进行分析对比,并将数值分析的结果同施工监测数据进行对比,得出以下结论:⑴在扩挖过程中,建议扩挖完成后尽早将支护结构封闭成环,这样不仅对围岩的稳定性有利,也同样有利于对扩挖隧道附近的围岩中的地下水保护;⑵采用变形CRD法、层层剥皮法,三台阶法进行开挖时,围岩稳定性、支护结构内力等均差异不大,在地下水发育不明显的情况下,建议根据当地的工程地质进行恰当选择。
Taking Chengdu-Chongqing high-speed Songinagou No.1 tunnel as the engineering background,in view of the existing tunnel in situ of the expansion of the three expansion digging ways(deformation of CRD method,layer upon layer peeling method,three stage method),the vault subsidence,convergence,the plastic zone,the vertical stress of surrounding rock and initial the minimum principal stress were analyzed comparatively.And the results of numerical analysis and construction monitoring data were analyzed,the following conclusions were obtained:(1)in the process of expansion to dig,suggestion is enlargement dig as soon as possible after the completion of supporting structure closed loop,it is not only good for the stability of surrounding rock,also conducive to the expansion of the surrounding rock near the groundwater protection;(2)in the case that deformation CRD method,layer peeling method and three-step method are adopted for excavation,and the stability of surrounding rock and the internal force of supporting structure are not significantly different.In the case that the development of groundwater is not obvious,it is suggested to choose appropriately according to the local engineering geology.
作者
赖勇
张帅
Lai Yong;Zhang Shuai(Hehai College,Chongqing Jiaotong University,Chongqing 400045,P.R.China)
出处
《地下空间与工程学报》
CSCD
北大核心
2019年第S01期311-320,共10页
Chinese Journal of Underground Space and Engineering
关键词
隧道扩建
流固耦合
扩挖方式
数值分析
tunnel expansion
fluid-splid coupling
enlarge dig way
numerical modeling
