顶进工作坑开挖对下方隧道影响分析  

Influence of Excavation of Jacking Working Pit on the Tunnel Below

作　　者：张俊龙 ZHANG Jun-long(Southwest Survey and Design Group Co.,Ltd.,China Railway Siyuan Group,Kunming,Yunnan,650200,China)

机构地区：[1]中铁四院集团西南勘察设计有限公司,云南昆明650200

出　　处：《建材技术与应用》2023年第4期43-46,共4页Research and Application of Building Materials

基　　金：安徽省自然科学基金项目(2008085ME168)。

摘　　要：当顶进工作坑位于既有地铁隧道上方时,工作坑开挖需对下方既有隧道保护。通过对某顶进工作坑工程计算表明:既有隧道位于基坑正下方时,随着基坑开挖深度的增加,隧道拱顶和拱底的竖向沉降(隆起)逐渐增大;隧道拱顶竖向沉降随着卸载率的增大而增大;在隧道两侧及顶部进行注浆加固能明显减小或约束隧道周边土体变形,且隧道径向收敛会大幅度降低。When the jacking working pit is located above the existing subway tunnel,the protection of the existing tunnel below shall be considered for the excavation of the working pit.Through the calculation of a jacking work pit,it is shown that when the existing tunnel is located directly under the foundation pit,the vertical settlement(uplift)of the tunnel arch top and arch bottom gradually increases with the increase of the excavation depth of the foundation pit.The excavation depth of foundation pit is an important parameter that affects the deformation of soil and tunnel.The vertical settlement of tunnel vault increases with the increase of unloading rate.Grouting reinforcement is carried out on both sides and the top of the tunnel.The grouting reinforcement can significantly reduce and restrict the deformation of the soil around the tunnel,and the radial convergence of the tunnel after grouting reinforcement is also greatly reduced.

关 键 词：顶进工作坑 下方隧道 竖向沉降 注浆加固 

分 类 号：TU47[建筑科学—结构工程]