Issue 51

B. Zaoui et alii, Frattura ed Integrità Strutturale, 51 (2020) 174-188; DOI: 10.3221/IGF-ESIS.51.14 177 quarter of a distance from the nodes belonging to the considered crack head. The mesh of the crack head was exclusively refined using this special type element (Fig. 2). Figure 2: The finite elements model. a) Boundary conditions, b) Total mesh of structure, c) Refined mesh in the vicinity of the crack heads. The side sizes of an element, far from the crack and in the crack vicinity, were represented in Tab. 1, these sizes and types of mesh, remains the same for all the simulations in this study, to avoid any influence of the mesh on the results. The different components of the analysed structure Numbers of elements Sizes of elements metal matrix 115200 0.001mm Crack front 280 0.001mm Fibres 104000 0.001mm Composite material globally 219480 0.001mm Table 1: Numbers and sizes of the mesh elements. Reinforcement materials are assumed to be elastic linear isotropic and the matrix is elastic linear isotropic also, whose mechanical and physical characteristics are grouped in Tab. 2. The criterion to predict the angle at which a pre-existing crack is propagate used in this work, is the maximum energy release rate criterion (MERR), it is based on the work of Hussain et al. (1974), Nuismer (1975), Palaniswamy and Knauss (1978), as well as Wu (1978). This criterion proposed in abaqus documentation.