散体材料桩复合地基桩土应力比分析  

Bearing capacity calculating method of discrete material pile composite foundation

作　　者：赵明华[1] 张玲[1] 刘敦平[1] 

机构地区：[1]湖南大学岩土工程研究所,湖南长沙410082

出　　处：《中南大学学报（自然科学版）》2007年第3期555-560,共6页Journal of Central South University:Science and Technology

基　　金：国家"863"计划项目(2006AA11Z104)

摘　　要：对散体材料桩复合地基承载力机理及影响桩土应力比的主要因素进行分析与探讨;针对散体材料桩受荷时不仅产生竖向固结,而且伴有侧向鼓胀这一变形特性,基于弹性理论解析,导出线弹性状态下桩体及桩周土的应力-应变关系,进而得出正方形布桩和梅花形布桩这2种典型布桩方式下桩土应力比的计算公式,并在此基础上,分别对桩体和桩间土体进行时效分析;基于弹性理论及太沙基一维固结理论,导出考虑时间效应的桩土应力比计算公式。采用所提出的计算方法对某工程实测结果进行分析与比较,其结果表明,考虑时效后桩土应力比随时间的增加而逐步提高,且理论的桩土应力比变化曲线与实测曲线较吻合。The bearing capacity of discrete material pile composite foundation and the main influencing factors of pile-soil stress ratio were discussed, respectively. Based on elastic theory analytic solution, a new calculating method for stress concentration ratio was presented, which was directed towards the deformation performance, that is, the discrete material pile not only had a vertical deformation but also had a lateral deformation under the vertical upper loads. This method can consider both the lateral deformation of discrete material pile under the vertical load and the influence of pile＇s arrangement. In addition, the aging effect of both discrete material pile and surrounding soil were analyzed. Based on the elastic theory and Terzzaghi＇s one dimension consolidation theory, a modificatory method for stress concentration ratio which took the aging effect into account was proposed. Lastly, a model experiment was analyzed to validate the method proposed. The result shows that the calculated curve agrees well with the measured one.

关 键 词：散体材料桩 复合地基 桩土应力比 侧向鼓胀 时效 

分 类 号：TU473.1[建筑科学—结构工程]