Numerical investigations on early indicators of fracture in concrete at meso-scale

Fracture is a major reason of the global failure of concretes. The understanding of fracture is important to ensure the safety of structures and to optimize the material behaviour. In particular an early prediction possibility of fracture in concretes is of major importance. In this paper, concrete fracture under bending was numerically analysed using the Discrete Element Method (DEM). The real mesoscopic structure of a concrete beam was modelled based on mu CT images. The calculations were performed under 2D and 3D conditions. The special attention was laid on the evolution of a macro-crack and different micro-structural phenomena during fracture before macro-cracking.