Computational Modelling of Particle Packing in Concrete

Physical particle packing is becoming a hot topic in concrete technology as more and more types of granular materials are used in concrete either for ecological or for engineering purposes. Although various analytical methods have been developed for optimum mixture design, comprehensive information on particle packing properties is still missing, e.g. on the impact of the packing method on such properties. Computer simulation therefore provides a promising perspective for particle packing simulation. However, developing flexible algorithms for simulation of arbitrary shaped particle packing still remains a challenge for concrete researches. This study aim offers a solution for these problems. The strategy of simulating particles of arbitrary shape is based on an experimental approach to this problem. The simulation strategies are thereupon implemented into a DEM-based dynamic concurrent algorithm-based simulation (CAS) approach for particle packing. Finally, influences of particle shape, particle size and packing method on packing density are evaluated and discussed. This methodology renders possible producing virtual concrete on meso-level. In combination with FEM, the influence of particle packing on mechanical properties of concrete has been assessed in this way. In the same way the simulation of cement particle packing can be realized on micro-level. Upon simulation of hydration, the capacity of self-healing of cracks due to unhydrated cement is assessed by a DEM-based simulation system for different cement types and packing densities.Design and Construction - Section of Materials and Environment (M&E) and Section of Structural MechanicsCivil Engineering and Geoscience