Determination of intergranular and transgranular failure of mesoscale model concrete under mode-I fracture

This paper presents a theoretical study on the determination of intergranular and transgranular failure of mesoscale concrete under mode-I fracture. The material model for concrete is set up based on the three main meso structures, i.e. mortar, interface and aggregate. The failure of concrete is characterized by its morphological fracture features in direct tension. Concept of meso-level fracture criterion is proposed based on the mesoscale model concrete. A self-consistent finite stress model (SFSM) for concrete-like cementitious materials is established and the meso-level crack path criterion of concrete is presented based on the SFSM. Two kinds of determination method for the mesoscopic fracture index are presented. The probability of aggregate fracture is formulated based on the variation of aggregate fracture index. Moreover, sensitivity analysis indicates that, the main factors in the formulation of aggregate fracture index should receive sufficient attention in future experimental and numerical works.