Granular materials forming part of embankments, foundations, pavement structures, and rail trackstructures are subjected to both static and dynamic loads. As a result of these loads particle breakage may occur. Particle breakage causes settlements and a reduction in the hydraulic conductivity of the granularmaterial. Moreover, the elastic modulus and the shear strength of the granular material are also negatively affected. Granular crushing is a detrimental phenomenon that deserves to be sudied in order to understand its causes, consequences, and ways to avoid it. Laboratory tests conducted on a weak granular material (sugar) and computer simulations (in the form of the Discrete Element Method, DEM) were usedto visualize, analyze, and understand the evolution of crushing in granular materials. The original DEM was modified to include the possibility of particle fragmentation. A tensile failure criterion developed by the author was programmed and incorporated into a commercial DEM code (PFC2D). The breakage model was also used to study the evolution of crushing in practical geotechnical applications. Fractal theory was used to quantify the amount of crushing produced under different conditions of stress and strain. In particular, the fragmentation fractal dimension was used to describe the changes on the grain sizedistribution of the analyzed materials.
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