摘要
本文针对地基土变形模量变化影响地基沉降分析的问题。首先,从细观力学机理入手,引入本征应变的概念并利用Eshelby等效夹杂原理,研究土体细观结构与宏观性能之间的关系,建立了土体变形模量、土颗粒骨架变形模量与土孔隙率之间的关系模型。随后,针对地基变形的非线性特征,引进分级加载思想,建立了在初始地应力和附加应力作用下的地基土变形模量以及孔隙率的递推变化关系模型。然后,引进分层总和和分级加载思想以及增量广义虎克定律,建立了能反映地基土变形模量变化影响的地基沉降计算方法。该方法充分体现了地基沉降变形的非线性特征,不仅能反映变形模量变化对地基沉降分析的影响,还能有效避免地基沉降分析须采用地基土压缩试验曲线或地基静载试验曲线。最后,通过工程实例计算,并与现有同类方法进行比较分析,表明了本文方法的合理性与优越性。
The focus of this paper is on the effect of changes in soil deformation modulus on the analyses of foundation settlement. Beginning with the mechanism of micro-mechanics, the concept of eigenstrain and the Eshelby equivalent inclusion are introduced. The relationship between the micro structure and macroscopic properties of soil is examined. The relation model between the soil deformation modulus, the deformation modulus of soil particles skeleton and the soil porosity is established. The nonlinear characteristic of foundation deformation is considered, the step-loading method is introduced, and a recurrence relation model between the soil deformation modulus and soil porosity under the initial ground stress and the additional stress is established. The layer-wise summation method, the step-loading method and the general Hooke＇ s law are introduced, a new ground foundation settlement analysis method which can reflect the changes in the deformation modulus is proposed. This method can reflect the nonlinear characteristics of the foundation settlement. It not only can reflect the effect of the change in soil deformation modulus on the analyses of foundation settlement, but also can avoid the use of the compression curves of ground soils and the static load test curves of ground foundation. The computation and analysis with practical engineering examples as well as comparisons between the measured and calculated settlement results with the other existing methods show that the model and method are more reasonable and feasible.
出处
《水文地质工程地质》
CAS
CSCD
北大核心
2016年第6期59-65,共7页
Hydrogeology & Engineering Geology
基金
国家自然科学基金项目资助(51378198)
高等学校博士学科点专项科研基金项目资助(20130161110017)
关键词
地基沉降
变形模量变化
体积应力
分层总和
分级加载
ground foundation settlement
variation of deformation modulus
volume stress
layer wisesummation method
step-loading
