模拟土体本构特性的热力学方法  

Thermomechanical approach to modeling constitutive behaviors of geomaterials

作　　者：孔亮[1] Ian F. Collins 

机构地区：[1]宁夏大学固体力学研究所,宁夏银川750021 [2]奥克兰大学工程学院,新西兰奥克兰92019

出　　处：《岩土力学》2008年第7期1732-1740,共9页Rock and Soil Mechanics

基　　金：国家自然科学基金项目(10402014);新世纪优秀人才支持计划项目(NCET-05-0895)

摘　　要：简要介绍了建立岩土材料弹塑性本构模型的热力学方法。它不仅具有紧凑的数学结构,而且自动满足热力学定律,仅从两个热力学势函数,即自由能函数与耗散增量函数出发,就足以导出弹塑性理论必须的屈服条件,流动法则,硬化定律和弹性定律。通过理论证明指出,只要耗散增量函数依赖于当前应力,流动法则必然是非关联的,岩土材料的摩擦特性与非关联流动法则密不可分。介绍该方法在三维模型,岩土材料的微细观力学特性,应力应变的均匀化以及剪胀和各向异性方面应用的主要研究进展,并对一些重要的概念,诸如"储存的塑性功","Reynolds-Taylor状态"等,进行分析与解释。最后给出近期需进一步深入研究的几点建议。The thermomechanical approach to establishing elastoplastic constitutive model for geomatefials is introduced briefly. The major attraction of this approach is that it not only provides a tight mathematical structure, but also satisfies the laws of thermodynamics automatically. The whole of the constitutive structure （yield condition, flow rule, hardening laws and elasticity law） is determined just from two thermodynamic potentials （the free energy and the increment of dissipation function）. It is demonstrated that, whenever the dissipation potential depends on the current stress; the flow rule is necessarily non-associated; and the concepts of friction and of non-associated flow rule are intimately linked. Then, some research advances, including three-dimensional problems, characteristic of geomaterials on micro and meso level, homogenization of stress-strain relation, dilation and anisotropy, are given. Several important concepts, such as ＂stored plastic work or frozen elastic energy＂ and ＂Reynolds-Taylor State＂, are explained and analyzed. Finally, some proposals for further research are made.

关 键 词：热力学 本构方程 弹塑性 土力学 岩土材料 

分 类 号：TU43[建筑科学—岩土工程] O344[建筑科学—土工工程]