深基坑施工对邻域钢管桩基础变形影响研究

Study on the Dynamic Response of the steel pipe pile foundation during Construction of Neighborhood Deep Excavation

钢管桩基础建筑物具有刚度大、施工周期短、工程质量高等特点,在建筑领域被广泛采用。若建筑桩基础侧方发生大面积卸荷,会对钢管桩基础建筑物造成严重影响。结合工程实测数据和数值计算结果,以厦门市某典型地铁车站深基坑工程为例,分析了深基坑施工对邻域建筑钢管桩基础变形的影响。研究结果表明:(1)在厦门地区土岩复合地层条件下,深基坑施工对邻域钢管桩基础的影响范围为2h(h为基坑深度),随着基坑开挖深度地增加,桩基沉降量及水平位移逐步增大;(2)钢管桩基础与混凝土桩基础沉降变形响应规律基本相同,钢管桩基础水平位移呈线性分布,混凝土桩基础水平位移存在明显拐点,拐点以下与钢管桩基本相同,拐点以上水平位移约为钢管桩的2倍。

Compared with concrete pile,the steel pipe pile has an advantage as high stiffness,high bearing capacity,high bearing capability,high quality and short construction term.Construction of deep foundation pit causing the unloading of neighborhood soil,inevitable role in the steel pipe pile foundation building.Combining with the actual measurement engineering data and finite element analysis,the deep foundation pit at the typical station on Xiamen metro line1is taken as the engineering background of this paper,the dynamic response of the steel pipe pile foundation during construction of neighborhood deep excavation was studied.The results indicate that,Under the condition of soil-rock compound stratum in Xiamen city,when the steel pipe pile location away from the edge of deep foundation pit1.7h(h:depth of deep excavation),the displacement of the steel pipe pile was generally small.The settlement displacement of concrete pile foundation and steel pipe pile foundation are basically the same,the horizontal displacement of the steel pipe pile foundation has a simple linear distribution.the horizontal displacement of the concrete pile foundation has obvious inflection point,under inflection point,the same as the steel pipe pile foundation,above inflection point,the horizontal displacement two times than the steel pipe pile foundation.Conclusions in this study can provide theoretical references for protection measures to similar projects.