摘要
异型的桩体几何形式增加了抗拔螺旋桩的桩土相互作用复杂性,抗拔试验研究有利于了解螺旋桩基础的承载机制和影响因素。通过16次原型桩抗拔试验,实测了单桩上拔荷载-位移曲线(U-Z曲线),该曲线表现出多拐点、渐进型特点,采用单位荷载的桩顶位移变化率、桩顶位移增量以及结合地基变形特征的方法判定了3种桩型的抗拔极限荷载。用U-Z曲线、lgU-Z曲线和P/Pu-Z曲线初步分析了桩体埋深、深宽比、首层叶片埋置深度以及叶片距宽比等参数对螺旋桩基础抗拔承载性状的影响。试验表明,抗拔螺旋桩的埋深、首层叶片埋置深度和叶片距宽比存在临界点,影响桩土的工作性状和破坏模式。
The pile-ground interaction of screw pile foundation is complicated because of the geometric abnormity body of pile; The pullout test of screw pile foundation has been carried out to analyze its bearing mechanism and influential factors. Through 16 groups of prototype pull-out test of screw pile foundation; the pullout load-displacement curves of single pile are measured. The curves of load-displacement （U-Z curves） show some inflection points and successive character. Using the U-Z curves, lgU-Z curves and P/Pu-Z curves, the pull-out working character of screw pile is analyzed in aspects of depth of pile, RDW （the ratio of depth of pile to the width of lamina）, DFL （the depth of first lamina） and RPDD （the ratio of distance between laminas to the net diameter）. It is shown there are some critical values of depth of pile, DFL or RPDD for pull-out test of screw pile foundation; and the working character and the failure mode of screw pile are affected by them.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2009年第1期186-190,共5页
Rock and Soil Mechanics
关键词
螺旋桩基础
抗拔试验
荷载位移关系
screw pile foundation
pullout test
relation between load and displacement
