Fracture mechanics of concrete and its role in explaining structural behaviour

Major steps forward in the history of the development of fracture mechanics, as a tool for describing or predicting the behaviour of concrete structures, have been the fictitious crack model, introduced by Hillerborg, and the compressive damage zone model, introduced by Markeset. In structural elements, however, often the conditions are less clear than in concentric tension or compression tests. The behaviour of concrete beams subjected to shear and slabs subjected to punching are illustrating examples, especially when size effects are concerned. Another phenomenon that required further study is the rotation capacity of slabs at intermediate supports. Since mostly the ultimate rotation is reached at failure of…