现浇X形桩复合地基桩侧摩阻力分布特性  

Behavior of Side Friction of X-section Cast-in-place Concrete Pile Composite Foundation

作　　者：刘汉龙[1,2] 吕亚茹[1,2] 丁选明[1,3] 金辉[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

出　　处：《中国公路学报》2012年第6期17-23,共7页China Journal of Highway and Transport

基　　金：国家自然科学基金青年科学基金项目(51008115);江苏省普通高校研究生科研创新计划项目(CXZZ12-0234);高速铁路基础研究联合基金重点项目(U1134207)

摘　　要：依托南京市桥北污水处理厂现场静载荷试验,应用ABAQUS软件分别建立了现浇X形单桩复合地基、群桩(梅花形布置和正方形布置)复合地基桩侧摩阻力的模型。结果表明:现浇X形桩中性点出现在桩长1/4～1/3深度处,负摩阻区明显存在但小于正摩阻区,是典型的摩擦型桩;侧摩阻力随桩体模量、土体参数和一定范围内桩长的增大而增大,随褥垫层厚度的增大而减小;布桩间距影响侧摩阻力的发挥,在允许的承载范围内,应尽量增大布桩间距,优化侧摩阻力的分布。Based on static load tests in Qiaobei sewage treatment plant in Nanjing,finite element models were established by ABAQUS for single pile and pile group with the configurations of equilateral triangle and square to simulate the distribution of side friction.The results show that the neutral points emerge at the 1/4 to 1/3 of pile depth.The area of negative friction is smaller than that of positive friction,in other words,X-section cast-in-place concrete pile（XCC pile） is a typical friction pile.The side friction increases with the increasing of pile modulus,surrounding soil modulus and pile length,and decreases with the increasing of cushion thickness.The capacity of side friction is affected by pile configurations.In order to improve the side friction,the pile spacing should be large enough within bearing capacity.

关 键 词：道路工程 现浇X形混凝土桩 有限元分析 桩侧摩阻力 群桩复合地基 

分 类 号：U416.1[交通运输工程—道路与铁道工程]