ABSTRACT
Numerical simulation tests were carried out using the distinct element method (DEM) paying much attention to the micro-deformation mechanism of granular materials flow in a silo. To do this, a modified version of DEM (MDEM), which can take into account the effect of rolling resistance at contacts, is used since it provides a powerful tool to investigate micro-deformation mechanism of granular assemblies under quasi-static loading. By using the DEM and MDEM, two-dimensional dry granular-material flows in a silo are simulated. Based on the simulations, we reach the following conclusions: (1) friction coefficient, as well as rolling resistance at contacts, has much influence on the discharge rate of the granular materials in the silo, (2) along the side-wall the shear band is generated, (3) a column-like structure is also generated near the sidewall. The column-like structure supports the load of granular materials and prevents the discharge rate from increasing, like a liquid. According to the shear deformation in the shear band, the column-like structures are destroyed and re-generated.
