From damage to fracture mechanics and conversely: A combined approach

Fracture mechanics and damage mechanics are two correlated theories. In some instances, e.g., for large specimens, crack propagation may be viewed equivalently as a sudden localization of damage. Relationships based on thermodynamic considerations between the two theories are presented in this paper. They lead to the definition of the equivalent crack concept, in passing from a damage zone to a fracture problem and, conversely, a damage zone is determined which is equivalent to a crack. Different possible applications are presented showing that, for the same problem, the two concepts can be used depending on the situation. Furthermore a solution to calculate fracture energy for large specimens, when damage parameters deduced from classical tests are known, is proposed to illustrate the capability of these equivalences. Copyright 0 1996 Elsevier Science Ltd.