新建隧道“零距离”下穿既有地铁车站结构变形分析

随地铁工程的迅速发展,下穿工程越发常见,如何预测和控制新建隧道下穿施工中对既有结构的影响,以保证既有机构的正常使用已成为设计者和科研人员的重要课题。结合深圳地铁7号线"零距离"下穿既有福民车站工程,通过数值模拟、监控分析等方法,研究下穿施工对车站既有结构的影响程度和范围。研究表明:下穿施工过程中,整体车站结构呈现轻微上浮的趋势,较大变形出现在隧道上方底板结构处及其两侧,与监测数据分析结果相符;车站楼板结构主应力主要以承受压应力为主,与隧道相接处承受最大主应力拉应力。通过数值模拟和监测对比分析,研究下穿施工影响规律,为类似工程提供参考和借鉴。

Deformation Analysis of Existing Subway Station Influenced by Newly-built Tunnel Passing Underneath it in"Zero Distance"

Along with the rapid development of subway projects ,underpass projects are increasing rapidly ,therefore how to forecast and control the influence of underpass projects to existing structures and ensure there operation have become an important issue .Based on the project of Shenzhen Metro 7th line passing underneath the existing Fumin station in "zero distance" ,this paper analyzed the influence degree and scope of underpass project to existing structure through numerical simulation and monitoring analysis methods . The results show that the whole station structure emerges slightly raised trend ,while large deformation occurs on floor which is above the newly-built tunnel ,and the monitoring data shows the same thing .The station structure mainly bear compression stress ,while the portion that connect with tunnel bear tension of major principal stress .It is effective to forecast the influence of tunnel construction through comparison analysis of nu-merical simulation and monitoring data which could provide reference for similar projects .