考虑桩顶刺入变形的刚性桩复合地基桩土应力比计算  

Calculation of Pile-soil Stress Ratio of Rigid Pile Composite Foundation with Consideration of Piles upward Puncture Deformation

作　　者：赵明华[1] 陈庆[1] 张玲[1] 

机构地区：[1]湖南大学岩土工程研究所,湖南长沙410082

出　　处：《公路交通科技》2009年第10期38-43,共6页Journal of Highway and Transportation Research and Development

基　　金：国家高技术研究发展计划(八六三计划)资助项目(2006AA11Z104);湖南省研究生创新基金资助

摘　　要：对荷载作用下刚性桩复合地基的变形特性进行了分析。在此基础上探讨了桩侧摩阻力与桩土相对变形的关系,进而根据桩-土-垫层变形协调条件,基于荷载传递法,引入"等沉面"概念,假定桩与桩间土均是理想线弹性体,等沉面上、下桩侧负、正摩阻力均沿桩长均匀分布,导得了刚性桩复合地基桩土应力比计算新公式,该公式综合考虑了桩侧正、负摩阻力,桩体上、下刺入变形以及桩径,桩长和土层性质等影响因素。最后应用所得公式对一个群桩复合地基试验的桩土应力比进行了计算,结果表明,当桩侧摩阻力充分发挥时,计算结果和试验结果较为接近。The deformation performance of rigid pile composite foundation under loading was discussed, and the relationship between the pile lateral friction and the piles-soil relative deformation was studied. By adopting the concept of the equal settlement section, the piles and the surrounding soil were assumed to be linear elastic masses, and the distributions of pile lateral frictions above and under the equal settlement section were assumed to be linear along the pile, respectively. On the basis of the deformation coordination condition of pile-soil-cushion and the load transfer method, a calculation formula of the pile-soil stress ratio of rigid pile composite foundation was proposed ~th consideration of positive and negative friction on piles, the upward and downward puncture deformations of piles, and the influence factors such as diameter and length of piles and soil layer property, etc. Finally, the pile-soil stress ratio in a group-pile composite foundation test was analyzed by the proposed formula.The result shows that the calculated result is close to the test result when the pile lateral friction exert sufficiently.

关 键 词：道路工程 刚性桩复合地基 桩土应力比 变形协调 刺入变形 负摩阻力 

分 类 号：U416.1[交通运输工程—道路与铁道工程] TU473.1[建筑科学—结构工程]