Issue 50

B. Benamar et alii, Frattura ed Integrità Strutturale, 50 (2019) 112-125; DOI: 10.3221/IGF-ESIS.50.11 115 40, 24.1, 24.1 *Damage Evolution, type=ENERGY, mixed mode behavior=POWER LAW, power=2.284 0.3, 0.6, 0.6 *Damage Stabilization 1e-05 *Elastic, type=TRACTION 10000. 10000., 10000. A NALYSIS he present study consists in a three-dimensional numerical analysis of tensile and compressive loaded (Fig. 2) with different overlap length in the first, then with geometrical modification in the second. A non-linear material and geometrical analysis was performed, using plane strain rectangular 8-node and triangular 6-node finite elements. Fig. 5 shows a detail of the mesh used at the assembly bond edge. In tensile behavior, the restraining and loading condition consists on clapping of the joint at one edge and applying a vertical restraint and tensile displacement at the opposite edge. The same thing in the compressive behavior but we restraint vertically all length except overlap region the both of the edge in order to favorite the separation, and the tensile replaced by the compressive displace. The choice of our geometric model in three dimensions, in single and double overlap with composite plates is standardized Mokhtari [27, 28]. See also the works of Benchiha [29] who carried out a study on the influence of defects and the work of Bezzerrouki [30], who has carried out several studies in this line of research. The assembled plates are three-dimensional, except for the two-dimensional joint adhesive designed as an interface. The third dimension (the thickness) is geometrically zero; it is introduced in the stiffness properties (Knn, Kss, Ktt). In this study, the joint adhesive was simulated as an interface. This modality allowed us to evaluate the release force under different parameters, such as adhesive, geometry and mechanical behavior. a) b) Figure 2 : Single lap bonded joint geometry. a) Tensile behaviour ; b) Compressive behaviour. The boundary conditions are not identical for both the tensile and shear behaviors. For the tensile behavior, it is easy to provoke the debonding with a small bending of the plates, so that they align in the same axis of traction where the adhesive is solicited in mixed mode. On the other hand, it is difficult to favor or provoke the detachment in compression behavior. Since the completely assembled system is free according to the normal, this results in large deformations in T