摘要
研究目的:随着城市的持续扩张和发展,地铁结构周边的工程开发愈发密集,尤其在软土地区,群基坑施工引起的结构变形影响复杂、风险高,已成为地铁运营部门关注的焦点。明确群基坑引起的结构变形非线性叠加特性,对邻近地铁结构安全运维至关重要。本文建立一种群基坑引起的非线性叠加增长规律的评价方法,构建群基坑开挖的邻近结构非线性变形叠加因子,基于某工程案例的数值计算结果,分析和探讨该叠加因子在群基坑多重卸载扰动下的变化规律,探究不同群基坑布局与开挖顺序对邻近地铁高架桥墩变形非线性叠加特征的影响。研究结论:(1)群基坑开挖影响下,邻近地铁桥墩表现出明显的非线性变形叠加变化特征;(2)对称双坑开挖在基坑距桥墩约3.5H(H为基坑开挖深度)范围内产生叠加变形影响;(3)不同开挖方式对桥墩总竖向位移影响差异较小,而对称基坑能显著减小桥墩水平位移;(4)采用同步开挖方式有利于控制群基坑对邻近环境影响,在先后开挖的情况下,应提出更严格的变形控制标准;(5)本研究成果对邻近群基坑等群体工程下地铁结构变形控制有一定的指导意义。
Research purposes:In the face of ongoing urban expansion and development,the density of engineering projects in proximity to metro structures has significantly increased,particularly in areas characterized by soft soil.The sophisticated and high-risk structural deformations induced by the construction of group foundation pits have garnered substantial attention from metro operations departments.Deciphering the non-linear cumulative characteristics of deformation triggered by grouped foundation pits is key to ensuring safe operations and systematic maintenance of metros.This paper establishes an evaluation method for the nonlinear superposition caused by group foundation pits,constructs a nonlinear deformation superposition factor of adjacent structures during group foundation pit excavation,analyzes the variation law of this superposition factor under multiple unloading disturbances of group pits based on the numerical calculation results of a case,and explores the influence of different group foundation pit layouts and excavation sequences on the nonlinear superposition characteristics of deformation of adjacent metro viaduct piers.Research conclusions:(1)Under the influence of group pits excavation,the neighboring metro piers show obvious nonlinear deformation superposition change characteristics.(2)The superimposed deformation influence of symmetrical double pits occurs within the range of approximately 3.5H from the foundation pit to the pier.(3)Different excavation methods have slight differences in the influence of the total vertical displacement,while symmetrical foundation pits can significantly reduce the horizontal displacement.(4)The use of simultaneous excavation is conducive to controlling the impact of group pits on the neighboring environment,and in the case of successive excavation,more stringent deformation control standards should be proposed.(5)The research findings are instructive for deformation control of metro structures under conditions of group engineering activities such as group foundation pits.
作者
吴楠
陈佩佩
杨光昌
吴鋆杰
单杰
WU Nan;CHEN Peipei;YANG Guangchang;WU Junjie;SHAN Jie(Suzhou City University,Suzhou,Jiangsu 215104,China;Intelligent Construction Research Base of Jiangsu Urban Underground Space Development and Utilization and Safety Protection Engineering Research Center,Suzhou,Jiangsu 215104,China;Beijing University of Civil Civil Engineering and Architecture,Beijing 100124,China;University of Science and Technology Beijing,Beijing 100083,China;Shanghai Key Laboratory of Rail Infrastructure Durability and System Safety,Tongji University,Shanghai 201804,China)
出处
《铁道工程学报》
北大核心
2025年第7期88-93,共6页
Journal of Railway Engineering Society
基金
江苏省第六期“333高层次人才培养工程”((2022)3-2-070)
苏州城市学院国家级项目预研课题(2022SGY012)
苏州城市学院科研启动费用资助(3110701923)。
关键词
群基坑
地铁
高架桥墩
变形特征
数值模拟
group foundation pits
metro
viaduct pier
deformation characteristic
numerical simulation
作者简介
吴楠,1980年出生,男,教授。
