ABSTRACT
Keywords: Concrete, Fracture Models, Cohesive Crack, Nonlocal Models, Softening Function, R curve, Equivalent Elastic Crack.
1 Introduction
Today, most experts accept that both the classical stress-strain formulations (plasticity and damage) and the classical linear elastic fracture mechanics (LEFM) are insufficient to deal with many practical structural problems involving fracture of cementitious materials and rocks. About 15 years ago, the pioneering works of Hillerborg on the single crack modelization and of Bazant on the band approach, led to the surge of the many models and approximations that emerged during these years. Most of the models, particularly the so called nonlocal, are very recent and there is not yet a comprehensive survey aimed at understanding their interrelation.
