复杂地质下临近地铁车站的深基坑支护变形研究

Study on deformation of deep foundation pit support near subway station under complex geology

临近的地铁车站会对基坑支护的变形情况产生一定的影响,研究基坑支护桩的变形规律对于基坑施工过程的稳定性及安全性至关重要,以盐田区梅沙街道小梅沙片区城市更新单元02-09、02-10地块基坑支护、土石方及桩基础工程为研究对象,建立其数值分析模型,分析其变形情况,得出以下结论:基坑中部存在“角部效应”,会导致支护桩的实测水平位移偏小,但是模拟值与实测值间的差值较小,且变化趋势具有一致性,说明采用数值模拟对基坑支护水平位移进行分析的可行性较高。在基坑开挖的前期,土体受到施工的扰动,其发生的水平位移较大,随着开挖的进行,在基坑支护的作用下,基坑周围的土体逐渐区域稳定,其水平位移增长较为缓慢。

The nearby subway station will have a certain influence on the deformation of foundation pit support,and it is very important to study the deformation law of foundation pit support piles for the stability and safety of foundation pit construction.Taking the foundation pit support,earthwork and pile foundation engineering of urban renewal units 02-09 and 02-10 in xiaomeisha area of Meishan Street in Yantian District as the research object,the numerical analysis model is established to analyze its deformation,and the following conclusions are drawn:there is"corner effect"in the middle of foundation pit.It will lead to the measured horizontal displacement of the supporting pile is small,but the difference between the simulated value and the measured value is small,and the changing trend is consistent,which shows that it is feasible to analyze the horizontal displacement of foundation pit support by numerical simulation.In the early stage of foundation pit excavation,the soil was disturbed by construction,and its horizontal displacement was large.With the progress of excavation,the soil around the foundation pit gradually stabilized under the action of foundation pit support,and its horizontal displacement increased slowly.