Mechanical behavior and shear band formation in idealized cemented sands by DEM
JIANG Ming-jing12, ZHANG Wang-cheng12, SUN Yu-gang12, ZHANG Fu-guang12
1. Department of Geotechnical Engineering, Tongji University, Shanghai 200092, China ; 2. Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education, Tongji University, Shanghai 200092, China
Abstract：Focus is placed on the mechanical behavior and shear band formation in idealized cemented sands by a series of DEM biaxial compression tests involving different bond strengths and confining pressures. The DEM software PFC2D is applied with user-defined contact model, which is resulted from the mechanical tests on the bonded granules idealized by two glued aluminum rods. The results show that the cemented sands have a higher strength and more significant post-peak softening and dilatancy than the reconstituted sands, and that the simulation is consistent with the laboratory tests and closely associated with the micro bonded contact mechanism. In addition, the shear bands in the cemented sands form with the simultaneous localization of micro parameters, such as deformed specimens, void ratio, averaged pure rotation rate (APR), displacement field and distribution of bond breakage.
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