3-D random packing of polydisperse particles and concrete aggregate grading

A new computer simulation method is presented in this paper for random packing of particles with variable sizes in the 3-D space. This method consists of two steps of simulation: kinematics and dynamics simulations. The kinematics simulation uses a 3-D cellular registration system for efficient particle deposition. The dynamics simulation models further packing of the matrix of particles using the Discrete Element Method (DEM). The numerical model can include a large numbers of particles in the matrix for packing. A number of important details omitted in previously proposed models now can be included to increase the fidelity, allowing one to consider random sizes and the 3-D locations of particles. Application examples show that this approach is effective, compared with physical experiment results. Its application to aggregate grading for Portland cement concrete is also presented here.