考虑群桩加筋效应的桩基沉降计算方法研究  

Study on settlement computation method for pile foundation by considering pile group reinforcing effect

作　　者：王卫东[1,2] 王阿丹[1] 吴江斌[2] 黄昱挺 

机构地区：[1]同济大学地下建筑与工程系,上海200092 [2]华东建筑设计研究院有限公司地下空间与工程设计研究院,上海200002

出　　处：《建筑结构学报》2016年第6期212-218,共7页Journal of Building Structures

基　　金："十二五"国家科技支撑计划(2012BAJ01B00);国家自然科学基金项目(51508522)

摘　　要：基于弹性半空间的Mindlin位移解的数值积分,结合叠加原理的Poulos弹性理论方法,对群桩进行沉降分析,但在工程应用中,对大型群桩的沉降结果偏大。为了得到合理的桩基沉降值,提出了三桩模型方法,该模型考虑了群桩加筋效应。为了进一步提高群桩加筋效应的计算效率,提出了加筋系数的概念,并推导了群桩加筋系数的矩阵表达式,进而提出了考虑遮拦-群桩加筋效应的群桩加筋系数分析法,并进行了相关的算例分析。结果表明:分析小型群桩沉降时,文中方法与Poulos法和Butterfield的边界元解结果均吻合较好;分析上海中心大厦的大型群桩沉降时,与Poulos法相比文中方法更接近实测值。Poulos elastic theory method based on the Mindlin solution in elastic half-space is suitable to study the settlement of the pile group by using superposition principle. This method may not be sufficiently accuracy when applied to large pile groups. The ignored but important pile group reinforcing effect was then supported by the proposed three-pile model in this paper. In order to improve the computation efficiency of this pile group reinforcing effect, reinforcement coefficient was proposed based on Poulos two-pile analysis. And then, the matrix expression of pile group reinforcement coefficient was derived and the pile group reinforcement coefficient method considering ＇sheltering-pile group reinforcing effect＇ was proposed finally. The relative example analysis shows that the proposed method agrees with the Poulos interaction factor method and the Butterfield＇ s boundary element method （BEM） for the settlement of small pile group. Calculation of the pile foundation of the Shanghai Center Tower indicates that the proposed method is more accurate than the Poulos interaction factor method.

关 键 词：群桩沉降 Poulos弹性理论法 群桩加筋效应 群桩加筋系数 

分 类 号：TU473.12[建筑科学—结构工程]