摘要
地铁车站浅埋暗挖大跨度隧道施工过程中,不可避免地需要拆除临时支撑,而拆除参数不合理或措施不当,极易发生支护体失稳、地面大面积沉降等问题。本文依托青岛地铁某暗挖大跨度车站,依据现场变形监测数据建立优化的数值模型,模拟开挖引起的变形分布规律和应力集中区域,在此基础上,通过分析不同拆撑长度下的二次沉降规律,确定了8m范围内交替拆撑、以8m为工作单元间隔拆撑的施工方案。并分析了经过锚索加固后,单次拆撑长度可由8m增加至12m。研究结论为实现信息化和安全高效施工提供了依据,也为今后类似工程积累了相关经验。
It is inevitable to remove the temporary support for the shallow buried and large-span tunnel in the subway station.However,the removal parameters are unreasonable,the measures are improper,and it is easy to cause the instability of the support body and the large area settlement of the ground.Therefore,based on the excavation of the large-span station in Qingdao Metro,an optimized numerical model is established according to the field deformation monitoring data to simulate the deformation distribution and stress concentration area caused by the excavation,and on this basis,by analyzing the secondary subsidence law under different brace removal lengths,the alternative brace removal within the range of 8 m is determined,and the brace removal construction with the interval of 8 m as the working unit is carried out.It is also analyzed that the length of single support removal is extended from 8 m to 12 m after the reinforcement with anchor cable.The study conclusion provides the basis for the realization of the information and safety construction and accumulates the relevant experience for similar projects in the future.
作者
王小凤
徐磊磊
Wang Xiaofeng;Xu Leilei(Shaanxi Railway Institute,Weinan 714000,China;The No.1 Engineering Co.,Ltd.of China Railway Beijng Engineering Group,Xi'an 710100,China)
出处
《工程勘察》
2022年第11期26-30,74,共6页
Geotechnical Investigation & Surveying
基金
陕西铁路工程职业技术学院2020年度教育教学改革基金项目(2020JG-30)
陕西省职业教育学会2019年度职业教育研究课题(SZJYB19-212)。
关键词
浅埋大跨隧道
数值模拟
拆撑优化
变形控制
shallow large span tunnel
numerical simulation
support removal optimization
deformation control
