紧邻既有车站和钢便桥的超大异形基坑施工方案优化  

Optimization of Construction Scheme of Ultra‑Large Special‑Shaped Foundation Pit Adjacent to Existing Station and Temporary Steel Bridge

作　　者：陈登伟 CHEN Dengwei(China Railway Southern Investment Group Co.,Ltd.,Shenzhen,Guangdong 518060,China)

机构地区：[1]中铁南方投资集团有限公司,广东深圳518060

出　　处：《中外公路》2024年第6期11-19,共9页Journal of China & Foreign Highway

基　　金：国家自然科学基金资助项目(编号:52008263);中国中铁股份公司科技研究开发计划课题(编号:2020-重点-14);中铁南方2020科技研发计划项目(编号:4403012022004346)。

摘　　要：随着中国城市地下空间开发密度不断增加,超大基坑施工对紧邻结构正常运营的影响不容忽视。该文依托深圳黄木岗综合交通枢纽工程,研究了超大异形基坑开挖引起围护结构和土体变形,以及紧邻既有车站变形和钢便桥的结构响应,并对该异形基坑开挖施工方案进行优化。结果表明:基坑南北侧围护结构的变形趋势整体一致,但北侧阳角处变形量较大;既有车站围护结构整体发生向坑内位移,最大水平位移达9.4 mm;基坑开挖后钢箱梁桥桩的水平位移较大,最大值达到10.5 mm。通过在负一层加设临时混凝土支撑和坑内钢便桥桥墩上增设钢套筒,保证了整体施工安全。With the intensifying development density of urban underground space in China,the impact of ultralarge foundation pit construction on the normal operation of adjacent structures cannot be ignored.Relying on the Huangmugang Comprehensive Transportation Hub Project in Shenzhen,this paper studied the deformation of the envelope structure and soil caused by the excavation of the ultra-large special-shaped foundation pit,as well as the structural response of the deformation of the adjacent existing station and the temporary steel bridge.The paper optimized the construction scheme of the special-shaped foundation pit excavation.The results show that the deformation trend of the envelope structure on the north and south sides of the foundation pit is the same as a whole,but the deformation at the external corner on the north side is large.The envelope structure of the existing station as a whole is displaced into the pit,with a maximum horizontal displacement of 9.4 mm,and the horizontal displacement of the steel box girder bridge pile after excavation of the foundation pit is large,with the maximum value reaching 10.5 mm.The overall construction safety is ensured by adding temporary concrete supports on the lower ground and adding steel sleeves on the piers of the temporary steel bridge in the pit.

关 键 词：超大异形基坑 基坑开挖 紧邻结构 数值计算 变形分析 

分 类 号：U416[交通运输工程—道路与铁道工程]