超高层建筑桩筏基础的桩顶反力计算研究

Study of computation of load on pile top of piled raft foundation for superhigh buildings

根据上海高88层、筏板厚度为4 m的金茂大厦和高101层、筏板厚度为4.5 m的上海环球金融中心桩筏基础的实测沉降资料,论证超高层建筑的桩筏基础为弹性体。对以上两幢超高层建筑和正在建造中的高121层、筏板厚度为6 m的上海中心大厦的桩筏基础,采用偏心受压公式和高层建筑与地基基础共同作用理论方法(混合法)进行详细对比计算,论证按弹性体计算桩顶反力的合理性,阐明《建筑桩基技术规范》(JGJ 94–2008)的3.1.8条的正确性和合理性。期望能够改变过去按偏心受压公式计算桩顶反力的传统观念,提高设计水平。

Based on the settlement data of the piled raft foundation in 88-storey, 4 m thick raft of Jinmao Building and 101-storey, 4.5m thick raft of Shanghai World Financial Center （SWFC）, it is demonstrated that piled raft foundation is a real elastic body. Meanwhile, the eccentric compression formula and method on interaction between superstructure and foundation （mixed method） are used to compute the load on pile top of piled raft foundation for two superhigh buildings just mentioned and 121-stroey, 6 m thick raft of Shanghai Tower which is under construction and compare each other in detail. The computed results have shown that the mixed method used is feasible and reasonable. It is hoped that the article 3.1.3 in China Technical Code for Building Pile Foundations （JGJ 94 - 2008） can change the traditional conception to use the eccentric compression formula for computing the load on pile top of piled raft foundation.