Collective random packing of disks in a plane under the influence of a weak central force

Some special effects in a 2D or 3D packing appear when this packing is made with particles belonging to an initially dense system. In order to achieve a better understanding of 'arching effects', a computer simulation of the collective random packing of disks in a plane under the influence of a weak central force has been set up. This work can be regarded as the first approach to the modelling of actual granular stackings resulting from mixing, pouring or fluidising particles. The dependence of the final packing fraction and mean coordination number on the initial density and on the step length has been studied on stackings of uniform disks. These functions can reach values as low as 0.76 and 3.40.