Meso-scale fracture modelling and fracture properties of rubber concrete considering initial defects

•A meso-scale fracture modelling with initial defects of rubber concrete is proposed.•The micropores and microcracks in ITZ are considered as initial defects in the model.•The fracture toughness reaches the maximum at 10% of rubber content.•The dimension-independent tensile strength and fracture toughness of rubber concrete were determined.