Modeling and mechanical influence of meso-scale concrete considering actual aggregate shapes

•Actual aggregate database was established combined with laser scanning technique and random cutting method.•The overlapping detection method of actual aggregate based on rectangular fitting was proposed.•Aggregate shape statistics of several meso-scale models with various sizes were provided.•Numerical experiments validate the significance of aggregate shape on concrete mechanical properties. Aggregate shape modeling is critical to concrete failure in mesoscale numerical simulation, However, most studies replaced actual aggregate with basic geometry, which caused the imprecise results. Combined with laser scanning technique and spatial random cutting, an actual aggregate database containing 1568 2D particles was formed. To realize rapid placement of particles with complex boundary, an indirect overlapping detection method based on rectangular fitting of aggregate is proposed, and the corresponding modeling method is also established. Uniaxial compression simulations of 30 cubes with different particle size groups were carried out, and parameter statistics of aggregate shape (elongation ratio, circularity and roughness) in the models were calculated. The results show that the effect of large size aggregate on the crack and strength is more obvious, and the difference in elongation ratio and roundness distribution of aggregate cause the fluctuation of concrete strength.