土岩复合地层坑中坑开挖变形及环境影响分析  

Analysis of Excavation Deformation and Environmental Impact due to Pit-in Pit Excavation in Soil-Rock Composite Strata

作　　者：白圻业 邱晨杰 蔡宗金 张小倩 陈锦剑[2] Bai Qiye;Qiu Chenjie;Cai Zongjin;Zhang Xiaoqian;Chen Jinjian(China Railway 24th Bureau Group Shanghai Construction Investment Co.,Ltd.,Shanghai 200020,China;Department of Civil Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]中铁二十四局集团上海建设投资有限公司,上海200020 [2]上海交通大学土木工程系,上海200240

出　　处：《科技通报》2025年第3期58-63,122,共7页Bulletin of Science and Technology

基　　金：国家自然科学基金项目(42377136)。

摘　　要：内坑紧贴外坑围护墙开挖时,内坑开挖将对外坑支护结构和临近环境产生较大影响。本文基于福州北站南广场综合改造工程,利用有限元软件建立土岩复合地层坑中坑开挖数值模型。基于数值模拟结果,分析了内坑开挖引起的围护结构变形、地表沉降、土压力分布以及应力场分布的演化特征,并研究了伺服轴力补偿系统对共用墙及环境变形的控制效果。结果表明:对于内外坑共用围护结构的基坑,内坑开挖引起共用墙被动区土压力减小,被动区土体有效应力减小,进而引起共用墙变形显著增加。先补偿轴力后开挖的方式可以有效减小共用墙的侧移增量和环境变形。研究内容对于超深超大基坑考虑坑中坑开挖工况对基坑支护结构及周边环境影响,掌握基坑变形机理以及控制环境变形具有借鉴及参考意义。When the inner pit is excavated close to the outer pit retaining structure,the inner pit excavation will have a significant impact on the retaining structure of the outer pit and the surrounding environment.Based on the comprehensive renovation project of Fuzhou North Station South Square,a numerical model of excavation in soil-rock composite strata is established.Through numerical simulation,the evolution characteristics of the deformation of the retaining structure,ground settlement,soil pressure,and stress field distribution caused by the inner pit excavation were presented in detail.The control effect of the servo axial force compensation system on the deformation of the shared wall and the environment was studied.The results show that the inner pit excavation causes a decrease in the passive soil pressure of the shared wall,a decrease in the effective stress of the soil,and a significant increase in the deformation of the shared wall.The method of compensating for axial force before excavation can effectively reduce the displacement increment of the environment and shared wall.The research content has reference and significance for considering the impact of pit-in-pit excavation conditions on the support structure and surrounding environment of deep-large foundation pits,clarifying the deformation mechanism of foundation pits,and controlling environmental deformation.

关 键 词：土岩复合 坑中坑 基坑变形 土压力 应力场 

分 类 号：TU476[建筑科学—结构工程]