原状湿陷性黄土的结构性本构模型

研究目的:黄土的应力和含水率状态对应着一定的结构状态,微观结构性的改变,引起宏观力学性状的改变。湿陷性黄土在力与水的共同作用下,产生原生结构性的损伤和湿陷变形,对增湿和加荷耦合作用下的结构性变化规律,应力应变关系和增湿变形等力学特性的研究有重要的意义。研究结论:不同含水率和固结围压条件下原状结构性黄土的应力应变变化规律,以及由增湿、固结作用和剪切变形反映了土体结构性损伤规律;统一考虑增湿和加荷对土体结构的损伤破坏,建立的反映结构性变化的非线性本构模型,能够描述应变软化和硬化型应力应变关系曲线,实现了土的结构性与其本构模型研究的统一。

Non- Linear Constitutive Model for Intact Collapsible Loess

Research purposes: The stress state and the rate of water content of the loess is corresponding to the special soil structure.That is to say the microcosmic structure variation results in the change of the macroscopical mechanics.Under the joint action of loading and moistening,the natural structure of the loess will be damaged and there will be collapse deformation.It is important to explore the variation laws of the structure and the mechanics characteristic of stress-strain relation and the moistening deformation under the joint action of the loading and moistening. Research conclusions:The variation law of stress-strain with the different rates of water content and the deformation due to the moistening,consolidation and shearing reflect the constitutive damage law of the soil body.On consideration of the damage of the soil body due to the moistening and loading,using the non-linear constitutive model for the constitutive variation can describe the relation curve between the strain softening and hardening stress-strain to realize the uniformity of the constitutive property and the research on the constitutive model.