Anisotropy and Mechanical Behaviour of Sand Pile Using 3D DEM Simulation

Abstract

Because of the anisotropy of the deposited granular material, its accumulation body has hidden danger in engineering. The problems of landslide and uneven surface settlement often occur in engineering. Drained triaxial compression tests under various pressure conditions were simulated by using MatDEM, aiming to investigate the macro-and mesoscopic mechanics and critical state characteristics of sand. Fabric tensors were introduced to quantitatively analyze the shearing-induced anisotropy, and the obtained data validates the stress-force-tensor relationship. Ten samples after isotropic consolidation and triaxial compression were then adopted to simulate the sand piling tests by removing the boundary. The stabilized sand piles were compared to examine the repose angle, distribution of base pressure, force chain, and anisotropy. The results indicate that the sample with higher initial anisotropy results in larger repose angle after piling, and the initial force arch and fabric anisotropy within the sheared sample lead to the pressure dip of sand pile. It was also found that the normal contact force anisotropy plays a leading role in the macro scopic characteristics of sand pile.

Keywords

• sand pile
• dem simulation
• fabric anisotropy
• repose angle