桩基变刚度调平设计的实施方法研究  

Study on implemention method for optimization design of pile foundation stiffness to reduce differential settlement

作　　者：王涛[1] 高文生[1] 刘金砺[1] 

机构地区：[1]中国建筑科学研究院,北京100013

出　　处：《岩土工程学报》2010年第4期531-537,共7页Chinese Journal of Geotechnical Engineering

基　　金：建设部科技项目(97-07-02);十一.五国家科技支撑计划课题-城市地下空间建造技术研究(20070106110131016)

摘　　要：针对高层建筑桩–箱、桩–筏基础反力、变形的实测结果显示,按常规理念设计的桩–箱、桩–筏基础有两点不足:一是碟形差异沉降引起上部结构较大次生应力;二是马鞍形的反力分布导致基础筏板内力增大。通过大比例尺模型试验结果分析,提出了以调整桩土支承刚度分布为主线,根据荷载、地质特征和上部结构布局,考虑相互作用效应,采取增强与弱化结合、减沉与增沉结合、局部平衡、整体协调,实现差异沉降、承台(基础)内力和资源消耗的最小化。对于变刚度调平设计,进行上部结构–基础–地基(桩土)共同作用分析,进一步优化布桩和承台配筋,结合工程实例对变刚度调平设计中的具体强化指数和弱化指数的取值进行分析说明。The measured data of foundations of high-rise buildings indicate that there are two shortcomings for those pile-box and pile-raft foundations designed by using the traditional design concept.One is disk-shape settlement distribution,which may result in the significant secondary forces in the super structure,and the other is the saddle-shape reaction distribution,which may result in the increase of punch force and moment in foundation slabs.In view of superstructure-soil-foundation interaction effect,the optimization design method for pile foundation and soil stiffness is put forward based on the loads,geological characteristics and superstructure layout by analyzing the field experimental results.The optimization design method adopts strengthening and reducing settlement,coupling hardness with softness,local balances,entirety harmony to realize differential settlement,cap internal force（foundation） and minimized resources consumption.Based on the conceptual design,the analysis of the interaction of superstructure-foundation-pile-soil helps to further optimize pile arrangement and reinforcements in the slab.An engineering case is taken as an example to analyze and interpret the application of strengthening index and avianizing index in the optimization design of pile foundation stiffness to reduce differential settlement.

关 键 词：桩基础 强化指数 弱化指数 共同作用 变刚度调平设计 

分 类 号：TU473[建筑科学—结构工程]