岩土力学2011，Vol.32Issue(10)：3148-3154,7.
桩基础双折减系数有限元强度折减法极限分析
Strength reduction of limit analysis finite element method for pile foundation by two reduction-factors
摘要
Abstract
The present safety factor of pile foundation judges the safe characteristic of pile-soil system integrally; but the mechanical character of pile is not clear for the end resistance and side friction of pile by using this safety factor. So, based on the bearing mechanism of end resistance and side friction of pile, and different proportion of two resistances to the total bearing capacity, the safety reserve factor of end resistance (F1) and the safety reserve factor of side friction (F2) are put forward; these two different safety reserve factors (SRFs) are objectively judged by strength reduction of nonlinear limit analysis FEM. The inflection points of F1-s curve and F2 - s curve, and the previous reduction-factors on the sharp point of V type of F1 - Qu curve and F2 - Qs curve are estimated as the safety reserve factor of end resistance and the safety reserve factor of side friction under the load condition. The analysis of FEM shows that the results of two reduction-factors method are near to the results of static load tests, the load increment method and a safe reserve factor method when the strength parameters of ground (c and <p) near to real parameters; and these inflection points of F1-s curve and F2 - s curve, and the sharp point of V type of F1-Qu curve and F2 - Qs curve have the specific physic purport; and the safety reserve factors of pile-soil system (F) by two reduction-factors method are close to the safety reserve factors of single reduction-factors method; and double safety reserve factors of F1 and F2 have some practicality in practice engineering.关键词
桩基础/有限元/极限分析/强度折减法/极限荷载/双折减系数Key words
pile foundation/ finite elements/ limit analysis/ strength reduction method/ ultimate load/ two reduction-factors分类
建筑与水利引用本文复制引用
董天文,郑颖人..桩基础双折减系数有限元强度折减法极限分析[J].岩土力学,2011,32(10):3148-3154,7.基金项目
辽宁省自然科学基金项目资助(No.20102103). （No.20102103）
