碎石桩复合地基性状的弹塑性分析  

Elastoplastic analysis of character for composite foundation with gravel columns

作　　者：刘杰[1] 赵明华[2] 

机构地区：[1]湖南工业大学岩土工程研究所,株洲412008 [2]湖南大学岩土工程研究所,长沙410082

出　　处：《岩土力学》2006年第10期1678-1684,共7页Rock and Soil Mechanics

基　　金：湖南省教育厅重点课题资助(No.04A058)。

摘　　要：基于双剪统一强度理论,利用复合地基中碎石桩与桩周土的竖向位移相等、侧向变形协调与连续的条件,通过弹塑性理论对碎石桩复合地基在竖向荷载作用下的应力、应变状态进行了弹塑性分析,探讨了权系数b的取值方法;讨论了b的大小对复合地基承载及变形性状的影响,并推出了作用在复合地基上的荷载、碎石桩所分担的荷载及加固区压缩量与桩周土的塑性区半径的关系的系列解析算式;提出了对于碎石桩复合地基的设计应该实行承载力和沉降双重控制的设计思想。为验证该方法的可行性,将模型试验的结果与计算结果进行了对比,结果表明该方法对碎石桩复合地基的设计具有指导意义。Based on the twin shear unified strength theory, and using vertical displacements equality, lateral deformation compatibility and continuum between gravel column and surrounding column soil in the composite foundation, stress-strain state of the composite foundation with gravel columns is analyzed by the elastoplastic theory under vertical load. Ascertaining methods for weight coefficient b are established. Influences of weight coefficient b on bearing and deformation character of the composite foundation are discussed. A series of analytical formulae, for example, between load exerted on the composite foundation or share load of gravel column or compression value of the reinforcement area and plastic area radius of surrounding pile soil, are drived. Design idea of double control on bearing capacity and settlement is suggested for the composite foundation with gravel columns. To make sure feasibility proposed method, results of model tests are compared with those of calculation; the comparison indicates that the proposed method has guidance significance for the composite foundation design with gravel columns.

关 键 词：双剪统一强度理论 碎石桩 复合地基 弹塑性理论 

分 类 号：TU472[建筑科学—结构工程]