Mesoscale fracture analysis of three-point bending concrete beams based on cohesive zone model

Abstract

Two-dimensional numerical simulations are carried out to investigate the fracture process of concrete three-point bending notched beams based on the mesostructure incorporating the cohesive zone model (CZM). The concrete mesostrucutre consists of aggregate particles, cement matrix, voids and the interfacial transitional zones (ITZ). The results show that the load–displacement curves and crack paths of the simulations are able to consistent with the experimental results. The study of model parameters highlights the initial stiffness (K0) for artificial compliance and the viscosity coefficient for improving numerical convergence. And the models with different softening laws (bilinear, exponential and linear softening) have noteworthy distinction in load-carrying capacity and energy dissipation. Moreover, the shapes of aggregate particles and void content are found to have significant influence on concrete cracking.