Abstract:A stereological type of fractal cohesive law is presented in this paper in order to describe more reasonably the soften behaviors of concrete under quasi-static uniaxial tensile loadings, in which the damage evaluation process of the fracture cross-sections and their distribution along the specimens’ axis are both considered. The derived numerical results are found to be in good agreement with the experimental data published in previous open literature. Additionally, the effects of aggregate grading type on the soften characteristic of concrete are analyzed by using the new cohesive model, which shows, under tensile loadings, that the more homogeneous the size distribution of the aggregates is, the stronger soften of concrete will be.