基于剪切位移折减法的深厚软土基坑支护桩墙沉降研究

Study on settlement of retaining pile wall in deep soft soil foundation pit based on shear displacement reduction method

以香港科技大学(广州)基坑支护工程为背景,考虑桩侧泥皮和桩底沉渣的影响,初步建立了剪切位移折减法的沉降估算模型。同时,详细分析了在小荷载作用下,深厚软土基坑中的支护桩墙的竖向受力变形特征。采用了剪切位移折减法,对未固结、欠固结及高灵敏度软土的工程实例和正常固结及微超固结软土的工程实例进行支护桩墙沉降估算,结果表明:剪切位移折减法较为简单实用,该法对未固结、欠固结和高灵敏度软土较为合适;对正常固结与微超固结软土,仅可作研究估算和定性判断使用。

Taking the foundation pit support project of Hong Kong University of Science and Technology(Guangzhou) as the background,considering the influence of pile side mud and pile bottom sediment,the settlement estimation model of shear displacement reduction method was preliminarily established.At the same time,the vertical stress and deformation characteristics of retaining pile wall in deep soft soil foundation pit under small load were analyzed in detail.The shear displacement reduction method was used to estimate the settlement of retaining pile wall in unconsolidated,underconsolidated and highly sensitive soft soil engineering examples and normal consolidated and slightly overconsolidated soft soil engineering examples.The results show that the shear displacement reduction method is simple and practical,and the method is suitable for unconsolidated,underconsolidated and highly sensitive soft soil.For normal consolidated and slightly overconsolidated soft soil,it can only be used for research estimation and qualitative judgment.