Geometrical Modelling of Concrete Microstructure

Daniel Rypl, Tomáš Bým

Department of Structural Mechanics
Faculty of Civil Engineering
Czech Technical University in Prague
Thákurova 7, 166 29 Prague, Czech Republic


This paper deals with the geometrical modelling of concrete microstructure. While there are many advanced models analyzing behaviour of concrete, they are mostly based on very simplified geometry of aggregate inclusions using either spherical or ellipsoidal shape. However, in many simulations such an approach may be unsatisfactory because realistic shape and distribution of aggregate particles is crucial for proper response. In such cases, it is highly desirable to properly incorporate aggregates of real shape in the geometrical model of concrete microstructure. In this work, the geometrical model of concrete is built using a suitable packing procedure, assembling individual aggregate particles, represented in terms of spherical harmonic expansion, into a representative volume. The model is then discretized into a finite element mesh by triangulating the surfaces of individual particles followed then by the tetrahedrization of the representative volume.