基于孔隙介质模型的散体材料桩复合地基沉降分层总和分析方法  

A Layer-wise Summation Analysis Method for the Settlement of Composite Ground with Friable Material Piles Based on Porous Medium Model

作　　者：曹文贵[1] 唐旖旎[1] 王江营[1] 

机构地区：[1]湖南大学岩土工程研究所,湖南长沙410082

出　　处：《湖南大学学报（自然科学版）》2014年第11期87-95,共9页Journal of Hunan University:Natural Sciences

基　　金：国家自然科学基金资助项目(51378198);高等学校博士学科点专项科研基金资助项目(20130161110017)

摘　　要：复合地基沉降计算是地基加固处理及相关设计的重要依据.基于刚性基础下散体材料桩复合地基沉降变形的特点,从桩与土微观变形力学机理研究入手,考虑其孔隙性质并引入孔隙介质分析方法,分别建立了反映桩与土表观变形力学参数与其骨架实际变形力学参数之间关系的孔隙介质模型.在此基础上,考虑桩与土变形力学参数的非线性特征,引进分级加载的思想,分别建立了附加应力和初始地应力对桩与土变形力学参数的影响模型,进而,建立了一种改进的散体材料桩复合地基沉降分层总和分析方法.通过工程实例分析并与现有方法计算结果进行对比,发现该方法不仅能反映桩和土变形力学参数随埋深和附加应力变化而变化的非线性特征,还能避免地基沉降计算中压缩试验曲线的使用,而且具有更高的计算精度,表明了该模型和方法的合理性与优越性.The settlement calculation of composite ground is an important basis of ground foundation reinforcement and design.Based on the characteristics of settlement and deformation of composite ground with friable material piles under rigid foundation,and considering the micro deformation mechanics mechanism of piles and soils,the porous medium models were developed by thinking over the porous nature of friable material piles and soils and introducing the analysis method of porous medium,which describe the relationships of the apparent deformation mechanics parameters of piles or soils versus the actual deformation mechanics parameters of their skeleton.Afterwards,by taking the nonlinear characteristics of the deformation mechanics parameters of piles and soils into account and importing an idea of step-loading,the patterns of the effect of additional or initial stress in composite ground on the deformation mechanics parameters of piles or soils were proposed,and then,an improved layer-wise summation method of settlement analysis of composite ground with friable material piles was put forward.Through the computation with practical engineering and the comparison with the calculated results by other existing methods,it shows that the method proposed can not only reflect the nonlinear characteristics that the deformation mechanics parameters of piles or soils change with depth or additional stress,but also avoid using the curves of compression tests,and has higher measurement accuracy,which indicates the feasibility and superiority of the proposed model and method.

关 键 词：地基沉降 散体材料桩复合地基 刚性基础 孔隙介质模型 分级加载 分层总和法 

分 类 号：TU472.1[建筑科学—结构工程]