Visualization of Crushing Evolution in Granular Materials under Compression Using DEM

Granular materials forming part of natural slopes, embankments, subgrades of foundations, and pavement structures are subjected to both static and dynamic loads during their engineering lives. As a result of these loads, particle crushing may occur. The present study demonstrates that the discrete-element method (DEM) can be used to visualize the evolution of this breakage process. In particular, the evolution of crushing in a simulated granular material subjected to uniaxial compression is presented. Even though DEM does not normally consider particle breakage, it is possible to simulate crushing by replacing one particle that has failed in tension with a combination of many particles of different sizes. The results from the simulation indicate that crushing does not develop uniformly throughout the sample, but rather concentrates in certain regions. These observations agree with experimental results of uniaxial tests conducted on sand. Other results from the simulation satisfactorily agree with experimental results previously reported by other researchers. In this way, by using a simplified failure criterion, DEM can be used to visualize and understand the evolution of granular crushing. This is something that is very difficult to do with laboratory tests alone.