基于热力学定律的土体动力Hardin-Drnevich模型再认识  

Recognition of dynamic Hardin-Drnevich model for soils based on generalized thermodynamics

作　　者：郭晓霞[1] 迟世春[1] 林皋[1] 

机构地区：[1]大连理工大学海岸与近海工程国家重点实验室,大连116085

出　　处：《岩土力学》2008年第9期2335-2340,共6页Rock and Soil Mechanics

基　　金：国家自然科学基金资助项目(No.50479057)

摘　　要：从Masing二倍法构造的Hardin-Drnevich模型的卸荷再加荷滞回曲线出发,以热力学定律为基础,考虑了塑性中心的移动为直线和骨架曲线两种情况下的耗散函数表达形式,应用Ziegler正交条件,通过对耗散函数求一阶偏导,得到耗散应力空间中的屈服函数表达式,并引入耗散应力和真实应力之间的差别项即转移应力,从而得到真实应力空间中的屈服函数。屈服曲线的绘制表明了对于塑性中心的不同转移规律,屈服曲线遵循同样的变化规律:应变在某一范围内,剪切形的屈服曲线是直线形式;当应变超过某一阈值时,剪切形的屈服曲线呈现弯曲。此外,还给出了应变的阈值。Starting from the unloading and reloading hysteretic curves of the Hardin-Drnevich model, different expressions of dissipation function are formulated in order to reconsider the energy dissipation mechanism of H-D model based on the thermodynamics principle. Two kinds of different translation rules of the back stress are assumed： one is the straight line; the other is the skeleton curve; and then the yield function expressions in the dissipative stress space are obtained by using of Ziegler＇s orthogonality condition. Moreover, adding the shift stresses to the dissipative stresses, the form of the yield condition in the true stress space is deduced. The plotting of yield curve in true stress space indicates that the form of the shear yield curve is straight line for the two different shift rules when the shear strain is below the threshold value. However, when the shear strain is above the threshold value, the shear yield curves appear bending.

关 键 词：动力本构模型 热力学 Ziegler正交条件 Masing准则 耗散函数 

分 类 号：TU435[建筑科学—岩土工程]