DCM桩复合地基受力变形性能有限元分析  

Deformation analysis of composite foundation with DCM piles by finite element method

作　　者：宋二祥[1] 付浩 郑天亮 李贤杰 SONG Er-xiang;FU Hao;ZHENG Tian-liang;LI Xian-jie(Key Laboratory of Civil Engineering Safety and Durability of Ministry of Education,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学土木工程安全与耐久教育部重点实验室,北京100084

出　　处：《地基处理》2019年第2期1-7,共7页Journal of Ground Improvement

基　　金：国家自然科学基金项目(51778339);国家973计划课题(2014CB047003)。

摘　　要：结合实际工程,就深层搅拌桩复合地基数值分析模型及作用机理进行研究。研究表明,对于带加筋垫层的复合地基,采用有限变形理论才能较好反映水平加筋垫层的承载作用;对于施工周期较长的工程,有必要模拟其饱和软土的固结过程,以正确计算桩土荷载分担及复合地基的变形;当桩与桩间土刚度相差悬殊的情况下,路堤的工后变形将高度依赖于其内所形成压力拱的长期稳定性,运营寿命内发生差异沉降的风险需要引起重视。In combination with the deformation analysis of an engineering project,the numerical model and mechanical mechanism of composite foundation with DCM piles are studied.It is revealed that finite deformation theory should be employed in the analysis to better reflect the bearing effect of the horizontally installed geotextiles in the cushion layer on top of the composite foundation;and staged construction as well as the consolidation process of the saturated soft soil should be simulated in order to calculate correctly the load sharing of piles and soil and the deformation of the composite foundation.The simulated results show that for such a composite foundation,where huge difference in stiffness exists between the piles and soil,the post-construction deformation of the filled embankment on top of the composite foundation will be highly dependent on the long-term stability of the pressure arches formed within the embankment,and the risk of differential settlement during the operation life should be taken into consideration.

关 键 词：搅拌桩复合地基 数值模拟分析 加筋垫层 有限变形理论 

分 类 号：TU43[建筑科学—岩土工程]