A container comprising 5,000 particles was simulated to investigate the role of particle shape on the bed structure of particulate materials. The effect of particle shape on the packing structure of granular beds was investigated in terms of bed height, the distribution of solid fraction, coordination number and the force acting at the bottom of the container. The solid fraction of the beds, which ranged from 0.7–0.9 for spherical particles and 0.6–0.8 for elongated particles, shows a compacted structure for beds of spherical particles. The average bed’s solid fraction was 0.825 and 0.750 for beds of spherical and elongated particles, respectively. The overall reduction in the average solid fraction was about 8% as aspect ratio of particles changed from 1 to 4. The solid fraction frequency distribution of the beds implied a wider variety of void shape and size for elongated particles. There was also a significant difference between the coordination number of spherical particles and nonspherical particles. The coordination number was 4.7 and 3.6 for spherical and elongated particles, respectively. However, the change in the magnitude of coordination number was greater (15.1%) in between beds of spherical and nonspherical particles (particles of aspect ratio 2), than in between beds with aspect ratio 2 and 4 (11.3%). The numerical results indicated that for a reliable prediction of real material behavior via discrete element models, the employed model should be capable of manipulating individual elements with shape as close as possible to the shape of real particles.

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