深厚粉细砂层深基坑临近地铁双排桩变形控制研究

Research on deformation control of double-row piles near metro deep foundation pit with deep silty sand layer

以郑州市中原科技城项目基坑临近运营地铁4号线车站为例,分析了黄河冲积平原区深厚粉细砂层基坑临近运营地铁车站变形控制时所面临的技术难点,在设计阶段进行有限元分析,分析计算基坑开挖土体卸载后对地铁产生的竖向和水平变形,并收集现场监测的测点数据与其测点相对应的计算结果进行对比,研究表明双排桩支护结构形式能够有效控制运营地铁变形,地铁变形最大值小于所允许的控制值,基坑开挖到最深处时,地铁工程变形达到最大值,随着地下室结构施工完成,变形增长会发生转折,朝着减小趋势发展。

Taking zhengzhou zhongyuan city science and technology project of foundation pit adjacent operating metro line 4 station as an example, analyzes the Yellow River alluvial plain silty sand layer deep foundation pit deformation control near the operating metro station, and the technical difficulties faced in the design phase of the finite element analysis, the analysis and calculation on the subway after excavation unloading of soil vertical and horizontal deformation. And collect the field monitoring point data comparing the calculation results, corresponding to its measuring point study form of retaining structure with double-row piles can effectively control the deformation. of the operating metro subway deformation is less than the maximum allowed by the control values, excavation to most deep place, the metro project reach maximum deformation. With the basement structure construction completion, the deformation of growth will change, the trend is towards reduction.