ETUDE DE L’ENDOMMAGEMENT DANS UN COMPOSITE STRATIFIE

Abstract

The use of composite materials in the naval environment is motivated by the mass gain and shows that these materials are mainly subjected to bending and tension, and that in most studies, the tension forces predominate. This implies that, in addition to conventional sizing of this stress and deformation of structure. Based on an adapted type modeling fracture mechanics, it is possible to predict by simulation the residual behavior of these thin structures containing damaged or manufacturing defects. The influence of damage to laminates using analytical models proposed by several researchers based on the perturbation of the stress and the effect of the multiplication of cracks on the stiffness is highlighted by many authers . Thus, using the finite element method, we consider the evaluation of damage in laminated plates subjected to any tension with crack, estimation and validation of numerical model calculations are based on the concepts of fracture mechanics. For modeling we will use the code ABAQUS. The stress distribution and evaluation of the stress intensity factor in a laminated composite shell semicircular in the presence of a notch have been investigated using the finite element method. The objective is to analyze the effect of fiber orientation on the variation of stress concentration at the notch and the stress intensity factor of a crack emanating from notch in the laminate loaded in traction. The results indicate that the maximum concentration factor of anisotropic normal stresses is of the order of a homogeneous material when the fibers are at 0 ° while the stress is doubled when the fibers are oriented between 80 and 90 °. Thus, we note that the energy of the crack is small when the fiber orientation tends to 90 °. From the latter, J energy increases substantially with decreasing angle. Increasing the length of the crack causes the speed increase in energy J.