（1 汉嘉设计集团股份有限公司， 杭州 310005；2 浙江大学滨海和城市岩土工程研究中心， 杭州 310058；3 浙江大学宁波理工学院土木建筑工程学院，宁波 315100；4 浙江理工大学建筑工程学院，杭州 310018）

［摘要］根据某续建工程桩筏基础加固方案的设计实践，利用ABAQUS软件建立了具有代表性的筏板-桩-土共同作用的三维有限元分析模型，分析了补桩桩长、补桩桩身强度和加固筏板厚度对桩筏基础的内力及变形特性的影响。分析结果表明：补桩桩长对筏板的沉降、弯矩均有较大的影响；补桩桩身强度对筏板沉降及原有桩的桩顶反力影响较小；加固筏板厚度的增大对筏板调节差异沉降和均衡原有桩筏系统内力有利，但同时也会导致整个筏板的自重增大、沉降增大。将桩顶反力和筏板应力的数值计算结果与实测结果进行了比较分析，两者较为吻合。

［关键词］桩筏基础; 筏板-桩-土共同作用; 数值分析; 内力特性; 变形特性

分类号：TU473.1       文献标识码：A       文章编号：1002-848X(2014)16-0091-05

Analysis on internal force and deformation characteristics of piled raft foundation of a continued project

Cen Zhengping1, Wang Guohua2,3, Xie Xinyu2,3, Ye Jun1, Liu Kaifu4, Zheng Lingwei2, 3

 (1 Hanjia Design Group Co., Ltd., Hangzhou 310005, China; 2 Research Center of Coastal and Urban Geotechnical Engineering, Zhejiang University, Hangzhou 310058, China; 3 School of Civil Engineering and Architecture, Ningbo Institute of Technology, Zhejiang University, Ningbo 315100, China; 4 College of Civil Engineering and Architecture,jiang Sci-Tech University, Hangzhou 310018, China)

Abstract: According to the reinforcement design practice for the piled raft foundation of a continued project, the three-dimensional finite element analysis model considering typical raft-pile-soil interaction was established by using ABAQUS software. The influences of the length and strength of supplementary pile and raft thickness on internal force and deformation characteristics of piled raft foundation were discussed. The results show that the length of supplementary pile has a great impact on the settlement and bending moment of the raft. The strength of supplementary piles has less effect on the settlement of the raft and the reaction force at the top of original pile. The increasing thickness of the raft, which brings positive effects on the adjustment of uneven settlement and internal forces of original piled raft foundation, increases the self-weight and settlement of the raft. The calculated results and field measured results on the reaction forces at the top of the pile and the stress of raft are in good agreement by comparing and analysis.

Keywords: piled raft foundation; raft-pile-soil interaction; numerical analysis; internal force characteristic; deformation characteristic

作者简介：岑政平，硕士，高级工程师，Email: yjhz0706@sina.com。

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