An effective stress-based DSC model for predicting hydromechanical shear behavior of unsaturated collapsible soils subjected to initial shear stress  

作　　者：Saman Soleymani Borujerdi S.Mohsen Haeri Amir Akbari Garakani Chandrakant SDesai 

机构地区：[1]Civil Engineering Department,Sharif University of Technology,Tehran,Iran [2]Power Industry Structures Research Department,Niroo Research Institute,Tehran,Iran [3]Department of Civil and Architectural Engineering and Mechanics,University of Arizona,Arizona,USA

出　　处：《Journal of Rock Mechanics and Geotechnical Engineering》2025年第1期539-555,共17页岩石力学与岩土工程学报(英文)

摘　　要：Evaluation of hydromechanical shear behavior of unsaturated soils is still a challenging issue. The time and cost needed for conducting precise experimental investigation on shear behavior of unsaturated soils have encouraged several investigators to develop analytical, empirical, or semi-empirical models for predicting the shear behavior of unsaturated soils. However, most of the previously proposed models are for specimens subjected to the isotropic state of stress, without considering the effect of initial shear stress. In this study, a hydromechanical constitutive model is proposed for unsaturated collapsible soils during shearing, with consideration of the effect of the initial shear stress. The model implements an effective stress-based disturbed state concept (DSC) to predict the stress-strain behavior of the soil. Accordingly, material/state variables were defined for both the start of the shearing stage and the critical state of the soil. A series of laboratory tests was performed using a fully automated unsaturated triaxial device to verify the proposed model. The experimental program included 23 suction-controlled unsaturated triaxial shear tests on reconstituted specimens of Gorgan clayey loess wetted to different levels of suctions under both isotropic and anisotropic stress states. The results show excellent agreement between the prediction by the proposed model and the experimental results.

关 键 词：Unsaturated collapsible soil Initial shear stress Hydromechanical shear behavior Effective stress Disturbed state concept Critical state 

分 类 号：TU443[建筑科学—岩土工程]