盾构井基坑围护结构数值模拟与现场变形监测分析研究

NUMERICAL SIMULATION AND FIELD DEFORMATION MONITORING ANALYSIS OF THE FOUNDATION PIT RETAINING STRUCTURE OF SHIELD WELL

以徐州市某始发盾构井基坑为研究对象,制订了基坑围护结构水平变形监测方案,重点分析了基坑开挖过程中围护结构水平变形与开挖深度的动态规律。通过有限元数值模型对基坑开挖过程施工进行动态模拟分析,并将数值模拟的理论值与现场监测结果进行对比分析,结果表明:有限元计算结果与现场监测结果比较一致,证明计算模型是合理的;基坑开挖深度与桩身水平变形值近似呈线性变化;桩身水平位移最大值在土层坑底上1~2m处;预应力及岩层可有效限制桩身水平位移。

Taking the foundation pit of shield well in Xuzhou as the research object,the horizontal deformation monitoring scheme of foundation pit retaining structure is formulated,and the dynamic law of horizontal deformation and excavation depth of retaining structure in the process of foundation pit excavation is emphatically analyzed.Through the finite element numerical model,the dynamic simulation analysis of the excavation process of the foundation pit is carried out,and the theoretical value of the numerical simulation is compared with the field monitoring results.The results show that the finite element calculation results are in good agreement with the field monitoring results,which proves that the calculation model is reasonable.The excavation depth of the foundation pit and the horizontal deformation value of the pile body are approximately linear.The maximum horizontal displacement of the pile is 1~2 m above the bottom of the soil pit.Prestress and rock can effectively limit the horizontal displacement of the pile.