Fracture mechanics parameters of concrete

The purpose of this paper is to set a scenario for discussing and comparing different models of concrete fracture. Using as a reference the cohesive crack model, as conceived by Hillerborg, it was found that simpler models—the equivalent elastic crack, the R-Δa curve approach, or models based on two parameters such as Bazant's and Jeng-Shah's—fit inside this scheme and are hierarchically related. For each approach, the theoretical background is reviewed, the experimental aspects are discussed, and the relevance to size effect predictions is considered. This review supplies criteria for comparing the different models and provides interpretation for the measured parameters with a unified language.