A three-dimensional cementation contact model for unsaturated structural loess
JIANG Ming-jing1, 2, 3, SUN Ruo-han1, 2, LI Tao1, 2, LIU Jun3
1. Department of Civil Engineering, School of Civil Engineering, Tianjin University, Tianjin 300072, China; 2. State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University, Tianjin 300072, China; 3. Department of Geotechnical Engineering, Tongji University, Shanghai 200092, China
Abstract：An adaptable three-dimensional (3D) contact model is necessary to perform discrete element simulation (DEM)on unsaturated structural loess, in which the effects of adhesive force and chemical cementation bond have to be taken into account. A 3DDEM contact model is introduced to simulate the macroscopic and microscopic mechanical behaviors of unsaturated and structural loess by considering the effects of adhesive force and chemical cementation. Interparticle adhesive force is composed of van der Waals attractions and capillary forces. Both bond stiffness and strength are associated with the bond size to represent unrecoverable chemical cementation. By using the relationships between water content and suction, a new 3D contact model for loess is established considering the coupling effects of water content-void ratio-suction. The DEM is used to simulate the triaxial and wetting tests at different deviator stress levels and the results show that the 3D contact model can well reproduce the macroscopic mechanical behaviors of unsaturated structural loess.
蒋明镜, 孙若晗, 李涛, 刘俊. 一个非饱和结构性黄土三维胶结接触模型[J]. 岩土工程学报, 2019, 41(S1): 213-216.
JIANG Ming-jing, SUN Ruo-han, LI Tao, LIU Jun. A three-dimensional cementation contact model for unsaturated structural loess. Chinese J. Geot. Eng., 2019, 41(S1): 213-216.
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