偏压深基坑开挖排桩围护结构变形规律分析

Deformation of Row Pile Retaining Structureforthe Biasof Deep Foundation Pit

基坑在开挖过程中，由于受到周边环境条件及工程地质条件的影响，围护结构的变形规律差别很大。本文以合肥地铁一号线6#风井深基坑为研究对象，依据排桩结构变形的实际监测数据与数值模拟的方法相结合，详细分析了在偏压荷载的作用下，基坑施工的各阶段围护桩体的变形规律，并分析了路基偏压对于基坑开挖的影响。研究结果表明：随着基坑开挖与支撑的架设，围护桩变形曲线呈现”弓形”变化，桩体的变形规律与支撑的架设位置、支撑的架设时间密切相关，围护桩体最大水平位移发生在基坑开挖深度的2／4～3／4的位置。通过对该基坑的分析，可以为相关工程提供参考。

During the construction of deep foundation pit, because of the environment and the engineering geological conditions, the deformation of the retaining structure vary greatly. In this paper, a deep foundation pit of No. 6 air shaft is taken as an example, combined actual monitoring data and the numerical simulation of row pile retaining structures, the deformation rules of the retaining structures wereanalyzed during every construction stage of deep foundation pit under the bias load, and the influence of foundation pit during excavation were also exploredunder the bias load. The results show that with the excavation of foundation pit and the erection of braces, the retaining pile is in a shape of bow, The deformation of pile is closely related to the erection position and the erection time, The maximum horizontal displacement of retaining pile happens at 2/4～3/4 depth of pit. The results can provide reference for related engineering.