消减沉桩挤土效应对大口径出水管影响的数值模拟与现场实测研究

Study on Numerical Simulation and Field Measurement of Reducing Soil Squeezing Effect of Pile Sinking on Large Diameter Outlet Pipe

结合上海某项目,测试沉桩施工对周边环境的影响过程,采用有限差分仿真软件先分别模拟在单一消减沉桩挤土效应措施工况下的出水管位移,再模拟综合消减措施工况下的位移,并对比验证了综合措施工况下的模拟数据与实测数据。在单一措施工况下,施加防振隔离沟、钢板桩隔断以及应力释放孔等措施能在一定程度上消减沉桩产生的挤土效应,应力释放孔工况下的消减效果优于其他两种单一工况;而对于施工场地范围内存在大口径出水管等敏感构筑物时,施加上部防振隔离沟+U形钢板桩阻断+应力释放孔相结合的综合性措施更能保证其安全。

Combined with a project in Shanghai,the impact process of pile sinking construction on the surrounding environment is tested.The finite difference simulation software is used to simulate the displacement of the outlet pipe under the condition of single measure to reduce the soil squeezing effect of pile sinking,and then the displacement under the condition of comprehensive measures.The simulation data and the measured data under the condition of comprehensive measures are compared and verified.Under the condition of single measure,anti-vibration isolation ditch,steel sheet pile partition and stress release hole can reduce the soil squeezing effect of pile sinking to a certain extent,and the reduction effect of stress release hole is better than the other two single conditions.For sensitive structures such as large-diameter outlet pipe in the construction site,the comprehensive measures of upper anti-vibration isolation ditch+U-shaped steel sheet pile blocking+stress release hole can ensure its safety.