摘要
本文通过黄土的三轴剪切试验,基于综合结构势的概念,建立了一个能够反映湿陷性黄土含水状态、应力状态和应变状态影响的结构性参数数学表达式。将结构性参数引入剪应力剪应变关系分析中,得到了考虑黄土结构性的应力应变关系。试验揭示了湿陷性黄土具有剪缩剪胀性,表明应力比与剪缩剪胀应变比之间具有良好的线性关系;固结围压越大,剪缩剪胀临界点的应力比越大,含水率越大,剪缩剪胀临界点的应力比越小。最终,建立了反映黄土结构性变化、应力应变软化与硬化、剪缩剪胀变形特性的本构模型。通过本构关系描述湿陷性黄土的应力应变发展过程,得到了与试验结果一致的变化曲线。
Based on the results of tri-axial compression tests of collapsible loess, a quantitative parameter of soil structural property, named as comprehensive soil structural potential, changing with the shear strain, was revealed. This soil structural parameter can be expressed by a function with some parameters related with water content, stress state and strain state, which is applied to the shear stress and shear strain relation. A constitutive model of unsaturated intact loess was obtained by the generalizing shear stress dividing by the structural parameter increasing monotonously with shear strain. The relation between dilatancy strain ratio and shear stress ratio can be described by a linear relation which is also verified by tri-axial compression tests. The critical state shear stress ratio increases with consolidation pressure, and decreases with the water content. Comparing the calculating stress strain curves with the testing curves the rationality of comprehensive soil structural potential constitutive model was verified by the consistency between simulating and measuring data.
出处
《水利学报》
EI
CSCD
北大核心
2006年第11期1315-1322,共8页
Journal of Hydraulic Engineering
基金
国家自然科学基金项目(101720701)
陕西省自然科学基金项目(2001c51)
关键词
综合结构势
黄土
欠压密
本构关系
structural parameter
unsaturated intact loess
dilatancy of loess
constitutive relation
