A microstructure-dependent hydro-mechanical coupled constitutive model for unsaturated soils
CAI Guo-qing1,2, WANG Ya-nan2, ZHOU An-nan3, ZHAO Cheng-gang1,2
1. Key Laboratory of Urban Underground Engineering of Ministry of Education, Beijing Jiaotong University, Beijing 100044, China; 2. School of Civil Engineering and Architecture, Beijing Jiaotong University, Beijing 100044, China; 3. School of Transportation Science and Engineering, Beihang University, Beijing 100191, China;
Abstract：Stress and hydraulic paths significantly affect the microstructure of unsaturated soil. On the other hand, different pore types and structures also have different impacts on mechanical and hydraulic behavior of soils with double-pore structures such as expansive soils and compacted soils. Based on the hydro-mechanical coupled constitutive model developed by Wheeler (GCM), the effective degree of saturation considering the different effects of macro and micro pores on the hydro-mechanical characteristics is introduced into the Bishop effective stress equation to take the influence of pore structure into account. On the basis of the effective degree of saturation, a microstructure-dependent hydro-mechanical coupled constitutive model for unsaturated soils is then proposed. The performance of the model is verified by various experimental data of isotropic compression tests and the predictions match the observations well, indicating the validity of the proposed model.
蔡国庆, 王亚南, 周安楠, 赵成刚. 考虑微观孔隙结构的非饱和土水-力耦合本构模型[J]. 岩土工程学报, 2018, 40(4): 618-624.
CAI Guo-qing, WANG Ya-nan, ZHOU An-nan, ZHAO Cheng-gang. A microstructure-dependent hydro-mechanical coupled constitutive model for unsaturated soils. Chinese J. Geot. Eng., 2018, 40(4): 618-624.
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