软土地区某高层建筑截桩纠倾关键技术研究  

Research on key technology for inclination rectification of cutting pile below a high-rise building in soft soil area

作　　者：杨学林[1] 祝文畏[1] 王擎忠 张林波 周豪毅 Yang Xuelin;Zhu Wenwei;Wang Qingzhong;Zhang Linbo;Zhou Haoyi(Zhejiang Prov-Institute of Architectural Design and Research,Hangzhou 310005,China;SenKee Construction Special Engineering Co.,Ltd.,Hangzhou 310030,China)

机构地区：[1]浙江省建筑设计研究院,浙江杭州310005 [2]杭州圣基建筑特种工程有限公司,浙江杭州310030

出　　处：《土木工程学报》2023年第9期136-145,共10页China Civil Engineering Journal

摘　　要：软土地区截桩纠倾技术复杂,桩基通过发生刺入变形而引起建筑物回倾。以往工程往往注重定性分析和防控措施的布置,目前尚缺乏合理的计算分析理论对端阻力与刺入变形的发展进行描述,无法准确预测截桩的数量,更无法计算纠倾期间的桩基及上部结构内力变化。截桩纠倾过程中,基桩内力处于动态变化之中,不同基桩甚至同一基桩不同阶段的荷载分布差异巨大,桩周以及桩端土的应力随之处在大幅度变化之中;导致建筑物倾斜的桩基缺陷难以准确参数化。文章在常规静载荷试桩Q-S曲线基础上,通过沉降监测对Q-S曲线进行调整和修正,建立基于考虑群桩效应、桩土相互作用以及桩基缺陷的等效Q(n)-S(n)曲线,并以此构建带缺陷基础与上部结构协同作用力学模型,在成功纠倾上海某软土地区高层建筑的基础上,为软土地区高层截桩纠倾提供一种分析、设计、施工和监测反馈同步的信息化纠倾方法。In the soft soil area,the inclination rectification method of pile cutting technique is complicated due to the tilting of building caused by the piercing deformation of piles.In the past projects,more attention was particularly paid to qualitative analysis and control measures,while in the present projects,the appropriate quantitative analysis theory for the description on the development of piercing settlement and base resistance is still absent,and it is difficult to accurately predict the amount of piles to be cut and impossible to further calculate the internal force of pile foundation and superstructure during the inclination rectification period.The internal forces of piles changes dynamically throughout the cutting process of pile.The load distribution on the piles varies tremendously during the pile cutting process,which causes the significant change in the stress of soil at the base and along the shaft.This variation finally leads to the difficulties in the parameterization of pile inclination.Hence,based on ordinary static load testing,an equivalent Q(n)-S(n)curve concerning the pile group effect,pile defect and the interaction of piles and the soil is established,by applying the monitored settlement results to the adjustment and correction of the Q-S curve.On basis of the Q(n)-S(n)curve,a mechanical model for a coordinately working system composed of the defective foundation and superstructure is proposed.As this method has been successfully applied to the rectification of the inclination of a high-rise building on soft ground in Shanghai,it may provide an informationized inclination rectification method of synchronized feedback for analysis,design,construction and monitoring.

关 键 词：截桩纠倾 软土地区 等效Q-S曲线 刺入变形 信息化 

分 类 号：TU470[建筑科学—结构工程]