考虑桩土滑移和鼓胀影响的碎石桩复合地基沉降分析方法  

A study of settlement calculation of the gravel pile composite ground considering the influence of slip between pile and soil as well as lateral displacement

作　　者：曹文贵[1] 杨泽华[1] 

机构地区：[1]湖南大学岩土工程研究所,长沙410082

出　　处：《水文地质工程地质》2012年第5期42-48,共7页Hydrogeology & Engineering Geology

基　　金：国家自然科学基金(51078137);高等学校博士学科点专项科研基金(20090161110005)

摘　　要：本文在深入研究柔性基础下碎石桩复合地基变形力学机理的基础上,结合单元体桩周土位移模式建立出柔性基础下碎石桩复合地基沉降分析方法。首先,根据柔性基础下碎石桩复合地基桩土界面上存在相对滑移的特点对现有竖向位移模式进行改进,然后,考虑到碎石桩复合地基桩体侧向鼓胀不可忽视的特征,在位移模式分析方法中计入径向位移的影响,并且由此得到桩侧摩阻力的分析方法,最后,通过对该模型的受力分析得到复合地基加固区压缩变形分析方法。该方法不仅能反映桩土间的相互作用以及复合地基桩土滑移的特征,而且能考虑碎石桩体鼓胀变形对复合地基沉降分析的影响。最后通过工程实例分析,表明了本文方法的可行性与合理性。Based on a thorough study of the deformation mechanism for gravel pile composite ground under flexible foundation, a new method for gravel pile composite ground settlement analysis is set up by using the soil displacement in a unit cell mode. Firstly, the existing vertical displacement model is improved for considering the relative slip between pile and soil in gravel pile composite ground under flexible foundation . Secondly, because the lateral displacement for gravel pile in composite ground cannot be ignored, the analysis method is combined with the influence of the radial displacement. The method for analyzing the friction on pile-soil interface is established. Finally, through the analysis of the unit cell model the analysis method for the displacement in the treated area is obtained. The analysis method can not only reflect the interaction between pile and its surrounding soils as well as the characteristics of slip between piles and soil, but also consider the influence of the lateral deformation of the gravel pile in composite ground settlement analysis. The engineering examples show that the method proposed in this paper is of feasibility and rationality.

关 键 词：柔性基础 碎石桩复合地基 桩土相对滑移量 鼓胀 沉降 

分 类 号：TU472.35[建筑科学—结构工程]