上软下硬地层大跨暗挖地铁车站拱盖法施工力学效应研究  

Study on construction mechanics effect of arch cover method for underground subway station with upper soft and lower hard strata

作　　者：麻凤海[1] 张雨 MA Fenghai;ZHANG Yu(School of Architectural Engineering,Dalian University,Dalian 116622,China)

机构地区：[1]大连大学建筑工程学院,辽宁大连116622

出　　处：《辽宁工程技术大学学报(自然科学版)》2025年第1期52-61,共10页Journal of Liaoning Technical University (Natural Science)

基　　金：国家自然科学基金项目(51474045);大连市科技创新基金项目(2023JJ12GX012)。

摘　　要：为研究上软下硬地层大跨暗挖地铁车站拱盖法施工的力学效应,以大连地铁4号线东南山站为研究背景,采用数值模拟和现场监测相结合的方法,运用MIDAS-GTS/NX有限元软件,研究地铁车站拱盖法施工全程的围岩变形及稳定性并与现场实测数据对比分析。研究结果表明:地表沉降由车站中线向两侧逐渐递减,影响区域约为车站开挖跨度的2倍;围岩变形和应力具有明显对称性,拱部围岩以沉降为主,高边墙以隆起为主,拱部跨中向隧道净空入侵,大拱脚向围岩入侵;围岩最大主应力均为压应力,拱脚尖角部位存在应力集中现象;围岩塑性区作用位置随车站施工不断变化,最终集中作用于高边墙位置处;通过Peck公式预测地表沉降,验证在上软下硬地层中采用拱盖法施工的可行性,为实际工程施工提供参考。To study the mechanical effects of the arch cover method in the construction of large-span underground subway station with upper soft and lower hard excavation,taking the construction of Southeast Mountain Station on Dalian Metro Line 4 as the research background,a research method adjoining numerical simulation and on-site monitoring was adopted.MIDAS-GTS/NX finite element software was used to study deformation and stability of surrounding rock and contrastive analysis with on-site measured data.The research results indicate that surface subsidence shows a decreasing trend from the centerline of the station to both sides,and the affected region is about twice the excavation skip distance of the station.The variant and stress of country rock have apparent symmetrical characteristics,the surrounding rock of the arch is mainly caused by settlement,while the high side wall is mainly uplift,the arch spans invades towards the tunnel clearance,the large arch foot invades towards the surrounding rock;the von mises stress of the country rock is under compression,and there is a phenomenon of concentration of stresses at the closed angle of the arch foot;the location of the plastic region of the country rock change continuously with the build of the depot,and ultimately funnel into the high side walls.The verification of surface settlement is predicted using the Peck formula,and the feasibility of using the arch cover method for construction in upper soft and lower hard strata is verified,which provides a reference for similar practical projects.

关 键 词：暗挖地铁车站 拱盖法施工 围岩变形 Peck沉降预测 围岩塑性区 围岩最大主应力 

分 类 号：TU94[建筑科学—建筑技术科学]