High fidelity 3D mesoscale modeling of concrete with ultrahigh volume fraction of irregular shaped aggregate

Abstract

High fidelity mesoscale modeling techniques are of vital importance for exploration of mechanical behaviors and failure mechanisms of concrete. This paper presents an innovative approach in construction of 3D mesoscale models of concrete with ultrahigh volume fraction of randomly distributed irregular-shaped aggregate. The new modeling method combines Voronoi diagram-based method with take-and-place strategy. In this method, a database of irregular-shaped aggregate models is built based on computed tomography (CT) scan of real aggregates. Then the geometric models of concrete are constructed with the coarse aggregates generated by shrinking Voronoi cells and the fine aggregates packed through a modified take-and-place procedure. 3D mesoscale models of 50 mm × 50 mm × 50 mm concrete specimens are created by the proposed method and proven to bear a close resemblance to the real ones. Ultrahigh aggregate volume fraction up to 66.2 vol% is achieved in the model following the Fuller gradation. To demonstrate the reliability of the generated models, the results of finite element analysis for the epoxy polymer concrete under uniaxial compression is compared with the experimental data. The simulation well reproduces the mechanical behaviors of the epoxy polymer concrete.