敏感地层中近距离基坑开挖对运营地铁隧道保护技术研究  

RESEARCH ON PROTECTION TECHNOLOGY OF SUBWAY TUNNEL IN SENSITIVE STRATUM BY EXCAVATION OF SHORT DISTANCE FOUNDATION PIT

作　　者：林泽辉 Lin Ze-hui

机构地区：[1]广州地铁设计研究院股份有限公司,广州510000

出　　处：《建筑技术开发》2022年第14期156-158,共3页Building Technology Development

摘　　要：以长沙市湘府路隧道明挖基坑上跨地铁1号线工程为依托,运用数值分析模拟和现场监测验证的方式,对敏感地层中近距离基坑开挖对运营地铁变形影响开展了研究,针对性提出了基底加固后的分段分步卸载封闭法基坑开挖技术。结果表明:数值计算结果与监测数据变化情况基本吻合,基坑开挖完成后最不利的竖向隆起值及水平收敛值分别达到5.71 mm,2.47 mm,均小于现行规范要求,可认为该措施能有效控制敏感地层中近距离基坑开挖下既有隧道结构的变形。In changsha city of hunan province road tunnel cut across the subway line 1 on foundation pit engineering as the backing,with the method of numerical simulation and field monitoring,close to sensitive formation in foundation pit excavation deformation influence of operating metro has carried out research,targeted put forward the basal step by step in different sections of the reinforced unload closed fermentation pit excavation technology.The results show that the numerical calculation results are basically consistent with the monitoring data.The most unfavorable vertical uplift value and horizontal convergence value after foundation pit excavation are 5.71mm and 2.47mm,respectively,which are both lower than the requirements of the current code.It can be considered that the method can effectively control the deformation of the existing tunnel structure under close foundation pit excavation in sensitive strata.

关 键 词：敏感地层 基坑开挖 分段分步卸载封闭法 变形控制 

分 类 号：TU753[建筑科学—建筑技术科学]