刚性荷载下现浇X形桩复合地基桩侧摩阻力数值分析  

Numerical analysis of side resistance of composite foundation with X-section cast-in-place concrete piles under rigid load

作　　者：吕亚茹[1,2] 丁选明[1,3] 刘汉龙[1,2] 吴宏伟[4] 

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]河海大学岩土工程科学研究所,江苏南京210098 [3]河海大学水资源高效利用与工程安全国家工程研究中心,江苏南京210098 [4]香港科技大学土木工程系,香港999077

出　　处：《岩土工程学报》2012年第11期2134-2140,共7页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金青年项目(51008115;51008116);国家自然科学基金高铁联合基金重点项目(U1134207);2012江苏省普通高校研究生创新计划(CXZZ12-0234)

摘　　要：作为异形截面桩,现浇X形桩承载特性主要受侧摩阻力特性的影响。采用有限元软件ABAQUS建立了三维X形桩和圆形桩单桩复合地基计算模型,对比分析了两种桩型的侧摩阻力分布特点和侧阻承载能力的差异。分别分析了X形桩侧摩阻力沿桩周和桩长的分布特性。结果表明:X形桩侧摩阻力和侧阻承载能力都优越于等截面积的圆形桩,在理想成桩条件下,X形桩侧摩阻力在0.9倍桩长深度处比圆形桩侧摩阻力有较大的提高。在水平方向,由于土拱效应,X形桩凸出段侧摩阻力为凹弧段的1.5～3倍。深度方面,X形桩凸出段侧摩阻力与凹弧段侧摩阻力比值沿深度逐渐增大。这些结论为X形桩的承载力设计计算提供了一定的理论依据。The bearing capacity of X-section cast-in-place concrete pile（XCC pile）,a special cross-section pile,is significantly influenced by side resistance.The single-piled composite foundation including XCC pile and circular pile is simulated by means of the finite element program ABAQUS.The side resistance and side bearing capacity are compared between XCC pile and circular pile.The distribution of side resistance of XCC pile is analyzed via cross-section plan and depth.The results indicate that both the side resistance and the side bearing capacity for XCC pile are better than those of circular pile,and that the side bearing capacity of XCC pile is significantly larger than that of circular pile at the relative depth of 0.9.At the cross-section plan,because of the soil arching,the side resistance of convex arc is about 1.5 to 3 times as large as that of concave arc for XCC pile.The ratio of the side resistance for convex arc to that of concave arc increases with the relative depth.The results are available for the design of XCC pile.

关 键 词：现浇X形混凝土桩 侧摩阻力 承载力 正应力 复合地基 

分 类 号：TU473[建筑科学—结构工程]