Simplified two-dimensional mesoscopic model for evaluating mechanical properties and crack paths near interfaces in concrete

•A new model (KAT model) of concrete that contains an interface is presented.•The coarse aggregate is uniquely modeled by hexagons of uniform size.•A new box-counting-method and finite element method are adapted to the model.•The crack paths and mechanical properties are analyzed with both methods.•The results are verified by comparison with experimental ones from concrete beam.

A new model for evaluating the crack paths and mechanical properties of concrete that contains an interface is presented. In this two-dimensional model, the coarse aggregate is modeled by hexagons of uniform size even though the real aggregate is mixture of various sizes. This simplified model is used for FEM analysis and also for analysis using the box counting method newly developed by the authors, which searches for the weakest route. The results from both analyses are verified by comparison with experimental results.