A thermodynamics-based three-scale constitutive model for partially saturated granular materials  

作　　者：Jianqiu Tian Enlong Liu Yuancheng Guo 

机构地区：[1]State Key Laboratory of Hydraulics and Mountain River Engineering,College of Water Resource and Hydropower,Sichuan University,Chengdu,610065,China [2]School of Geoscience and Technology,Southwest Petroleum University,Chengdu,610500,China [3]College of Civil Engineering,Zhengzhou University,Zhengzhou,450001,China

出　　处：《Journal of Rock Mechanics and Geotechnical Engineering》2024年第5期1813-1831,共19页岩石力学与岩土工程学报（英文版）

基　　金：the financial support from the National Key Research and Development Program of China(Grant No.2017YFC1501003).

摘　　要：A three-scale constitutive model for unsaturated granular materials based on thermodynamic theory is presented.The three-scale yield locus,derived from the explicit yield criterion for solid matrix,is developed from a series of discrete interparticle contact planes.The three-scale yield locus is sensitive to porosity changes;therefore,it is reinterpreted as a corresponding constitutive model without phenomenological parameters.Furthermore,a water retention curve is proposed based on special pore morphology and experimental observations.The features of the partially saturated granular materials are well captured by the model.Under wetting and isotropic compression,volumetric compaction occurs,and the degree of saturation increases.Moreover,the higher the matric suction,the greater the strength,and the smaller the volumetric compaction.Compared with the phenomenological Barcelona basic model,the proposed three-scale constitutive model has fewer parameters;virtually all parameters have clear physical meanings.

关 键 词：Unsaturated granular material Unsaturated porous material GEOMATERIALS Multi-scale constitutive model Water retention curve PLASTICITY 

分 类 号：TU41[建筑科学—岩土工程]