基于圆孔扩张理论的静压楔形桩沉桩挤土效应研究  

Study on Pile Sinking Compaction Effect of Hydrostatic Wedge Pile Using Cavity Expansion Theory

作　　者：周航[1,2] 孔纲强[1,2] 刘汉龙[1,2] 

机构地区：[1]河海大学岩土力学与堤坝工程教育部重点实验室,江苏南京210098 [2]河海大学土木与交通学院,江苏南京210098

出　　处：《中国公路学报》2014年第4期24-30,共7页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(51008116;51278170);高速铁路基础研究联合基金项目(U1134207);江苏省普通高校研究生科研创新计划项目(CXZZ13_02)

摘　　要：针对扩底楔形桩沉桩挤土效应特性方面的研究相对较少的状况,基于圆孔扩张理论,考虑扩底楔形桩的楔形角和扩大头等截面尺寸变化,建立扩底楔形桩施工中静压沉桩过程中沉桩阻力、桩周土体位移场以及超静孔隙水压力的理论计算方法。通过对楔形桩沉桩模型试验与理论分析的对比,分析了楔形角、沉桩深度、土体参数等因素对沉桩阻力、桩周挤土效应的影响规律。研究结果表明：所建立的理论计算方法能够较好的模拟楔形桩沉桩过程;沉桩完毕后侧摩阻力和桩端阻力之比在2~4之间,土体径向位移在距桩中心距离约为10倍桩径处递减为0。For the researches focusing on pile sinking effect of belled wedge pile are relatively few, base on cavity expansion theory, with the cross section of belled wedge pile （such as wedge angle and enlarged pile base etc. ） considered, theoretical calculation methods during wedge pile driving for pile sinking resistance, soil compaction displacement and excess pore water pressure were set up. Pile sinking effect model tests and theoretical analysis were performed for comparative analysis. The influences of wedge angle, pile sinking depth, and soil parameters on pile sinking resistance and soil compaction displacement were analyzed. The results show that the theoretical calculation methods established in this paper can simulate wedge pile driving effectively; the ratio of the side resistance and tip resistance is approximately 2 to 4 times and the soil radial displacement decreases to zero at the distance of 10 times of pile radius from the pile center.

关 键 词：道路工程 扩底楔形桩 圆孔扩张理论 沉桩阻力 挤土位移 超静孔隙水压 

分 类 号：TU473.1[建筑科学—结构工程]