A 2D elliptical model of random packing for aggregates in concrete

Abstract

In the present work, a computer model was developed to simulate random packing of aggregates. For the sake of simplicity, two dimensional situation was considered and all of the aggregates in concrete were assumed as ellipse. 2D elliptical models of random packing were firstly demonstrated in periodic boundary condition. In addition, the ellipse random packing model was employed for the influence of aspect ratios on the packing fraction of ellipses. The modeling results demonstrate that the packing fraction of ellipses firstly increases then drops down with increasing aspect ratio. The maximal random packing fraction is 0.66 when aspect ratio is 1.04 in the periodic boundary condition.

Keywords

ellipse / overlap / random packing / periodic boundary / aspect ratio / packing fraction

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