反井施工下竖井纵向变形曲线的研究  

Study on longitudinal deformation profile of shaft under raise-boring method

作　　者：陈航 侯义辉 王薇[3] 张燕飞 CHEN Hang;HOU Yihui;WANG Wei;ZHANG Yanfei(China Railway Tunnel group co.LTD.Municipal Engineering Company,Hangzhou,Zhejiang 310000,China;Shaoxing Traffic Construction Co.LTD,Shaoxing,Zhejiang 312000,China;School of Civil Engineering,Central South University,Changsha,Hunan 410075,China)

机构地区：[1]中铁隧道局集团有限公司市政工程公司,浙江杭州310000 [2]绍兴市交通建设有限公司,浙江绍兴312000 [3]中南大学土木工程学院,湖南长沙410075

出　　处：《石河子大学学报（自然科学版）》2021年第4期446-453,共8页Journal of Shihezi University(Natural Science)

基　　金：浙江省交通科技项目(2017041);湖南省自然科学基金项目(2018JJ2519)。

摘　　要：纵向变形(LDP)曲线是收敛约束法的重要组成部分,目前对LDP曲线研究主要集中于隧道开挖过程中各因素对LDP曲线的影响,较少探讨竖井开挖过程中围岩LDP曲线,因此,本文以杭绍台高速公路某隧道反井法施工竖井工程,采用有限元软件建立三维竖井开挖模型,考虑开挖面深度变化及围岩级别等因素,提出量化竖井正向扩挖过程的LDP曲线的函数表达式,并与隧道传统LDP曲线进行了对比分析。结果表明:竖井正向扩挖过程中,开挖面空间效应范围约为6倍开挖半径;开挖面深度及围岩亚类分级对LDP曲线影响较小,基本分级下,围岩越好,竖井开挖面下方曲线越陡峭,开挖面处位移突变越明显,开挖面上方曲线较平缓;竖井LDP曲线与隧道相比存在显著差异,表明开展反井施工下竖井LDP曲线的研究具有重要意义。LDP曲线的获得能为确定支护架设前井壁径向位移提供指导,并为本工程准确运用收敛约束法进行竖井支护设计及稳定性分析提供理论基础。Longitudinal deformation(LDP)profile is an important part of convergent constraint method.At present,researches on LDP curve mainly focus on the influence of various factors on LDP curve during tunnel excavation,but seldom discuss the LDP curve of sur-rounding rocks during shaft excavation.In this paper,based on a shaft by rasise-boring method in Hangzhou Taizhou Expressway tunnel,a three-dimensional shaft excavation model is established by finite element software.Functions of longitudinal deformation profile which consider the variation of excavation depth and surrounding rock grade during positive expanding excavation of shaft are given and are compared with tunnel traditional LDP curve.The results indicate that during positive expanding excavation of shaft,spatial excavation effect range are about 6 times shaft radius.Excavation depth and surrounding rock subclass classification have little influence on the LDP curve.Under the basic grading,the better the surrounding rock,the steeper the curve below the shaft excavation surface,the more obvious the displacement change at the excavation surface,and the curve above the excavation surface is gentler.The LDP curve have a significant difference between the shaft and the tunnel,which indicates that the study of the LDP curve under the anti-shaft construction is of great significance.The acquisition of the longitudinal deformation profile will provide guidance for determining the radial displace-ment of the shaft before the support is erected,and then provide a theoretical basis for the engineering to accurately use the convergence constraint method for shaft support design and stability analysis.

关 键 词：公路隧道 纵向变形曲线 数值计算 竖井 正向扩挖 

分 类 号：U455[建筑科学—桥梁与隧道工程]