可控刚度桩筏基础变刚度调平的工程实践  

Engineering practice of controllable stiffness pile-raft foundation for variable stiffness for balance

作　　者：朱锐 周峰 翟德志 常银生 屈伟 Zhu Rui;Zhou Feng;Zhai Dezhi;Chang Yinsheng;Qu Wei(College of Transportation Science and Engineering,Nanjing Tech University,Nanjing 210009,China;Nanjing Housing Safety Management Office,Nanjing 210009,China;Changshu Institute of Technology,Changshu 215500,China;Geotechnical Engineering Department,Nanjing Hydraulic Research Institute,Nanjing 210024,China)

机构地区：[1]南京工业大学交通运输工程学院,江苏南京210009 [2]南京水利科学研究院岩土工程研究所,江苏南京210024 [3]南京市房屋安全管理处,江苏南京210009 [4]常熟理工学院,江苏常熟215500

出　　处：《建筑科学》2018年第7期139-146,共8页Building Science

基　　金：国家自然科学基金面上项目(51778287);国家自然科学基金面上项目(51278244)

摘　　要：基底下的地基土支承刚度不均匀导致的建筑基础差异沉降问题在中软土及土岩溶组合地区较为突出,因此,减少其差异沉降是高层建筑桩筏基础设计中的关键点。本文介绍的典型工程采用以天然地基为主、部分区域内采用桩顶设置刚度调节装置的人工挖孔桩的变刚度调平设计方法,在解决因地基土差异沉降过大引起的差异沉降问题的同时,还充分利用了良好的天然地基承载力,取得了良好的经济效益和社会效益。通过现场测试数据与结果进行对比分析,验证可控刚度桩筏基础应用于该项目的合理性与可靠性。现场实测结果显示,本工程D区域采用可控刚度桩筏基础后,建筑物总沉降和差异沉降均满足设计要求,地基土分担了上部结构65%的荷载,充分发挥了地基土体承载力。设计思路及相关经验可供类似工程借鉴与参考。The uneven foundation settlement due to the uneven soil stiffness under the base in the soft soil and karst area is obvious,Therefore,reducing the differential settlement is the key point in the design of piled raft foundation of high-rise building. The typical engineering introduced in this paper adopts the variable stiffness method which is mainly based on natural foundation with manual digging pile equipped with deformation adjustors in partial area. The problem of differential settlement caused by uneven soil foundation stiffness is solved. It also makes full use of the good bearing capacity of the natural foundation,and good economic and social benefits are achieved. Through comparing and analyzing the field test data and results,the rationality and reliability of the application of the controllable rigidity pile raft foundation to the project are verified. Field measurement results show that,in this project,the total settlement and differential settlement of the building meet the design requirements when manual digging pile with deformation adjustors are used in the D area. And the ground soil shares sixty-five percent of the load of the superstructure,which means it gives full play to the bearing capacity of foundation soil.The design idea and relevant experience can be used for the similar projects.

关 键 词：地基土支承刚度 刚度调节装置 天然地基 变刚度调平 差异沉降 

分 类 号：TU473.1[建筑科学—结构工程]