上跨地铁双线隧道基坑工程MJS加固及分区卸载施工研究
Research on MJS reinforcement and sectional unloading construction of foundation pit engineering of double track subway tunnel
宋卫华1
作者信息
- 1. 徐州市产城发展集团有限公司,江苏徐州 221116
- 折叠
摘要
跨线基坑工程空间交叉施工会不可避免地对既有盾构隧道结构受力和变形产生影响,特别是当基坑开挖距离隧道施工完成时间较短时,施工卸载引起临界范围隧道的上浮量将会叠加,甚至造成管片上浮进而危害隧道的使用和运营.基于两阶段分析法和Pasternak地基梁模型,将注浆压力、水的浮力等因素考虑进隧道总变形中,推导出既有隧道变形的解析解.利用FLAC3D软件,基于土与结构相互作用模型,研究基坑分区开挖作用下隧道隆起值的变化规律,分析MJS法加固作用下隧道的应力场和位移场的变化规律,并进行了对比分析.研究结果可为同类工程施工提供一定的借鉴意义.
Abstract
The spatial cross-construction of cross-line pit projects will inevitably affect the stress and deformation of existing shield tunnel structures,especially when the excavation of the pit is carried out shortly after the tunnel construction is completed.The unloading caused by construc-tion will lead to an accumulation of the uplift amount within the critical range of the tunnel,and may even cause segmental uplift,thereby endangering the tunnel's usage and operation.Based on the two-stage analysis method and the Pasternak foundation beam model,taking into account fac-tors such as grouting pressure and the buoyancy of water,an analytical solution for the deforma-tion of existing tunnels is derived.Using FLAC3D software and based on the soil-structure inter-action model,the study investigates the variation pattern of tunnel uplift values under the action of segmented pit excavation,analyzes the changes in the stress field and displacement field of the tunnel under the reinforcement effect of the MJS method,and conducts a comparative analysis.The research results provide certain reference significance for similar engineering construction.
关键词
基坑开挖/上跨/MJS加固/数值模拟Key words
Pit excavation/over crossing/MJS reinforcement/numerical simulation引用本文复制引用
基金项目
江苏省高等学校自然科学研究项目(20KJA560003)
江苏省住建厅指导项目(2019ZD079)
出版年
2024
NETL
NSTL
万方数据