Some Local Problems in Laminated Composite Structures

Failure mechanisms for composite materials and especially for laminated composites are different and more complex than for homogeneous and isotropic materials. That is why modeling and analysis of such structures are done having as main goal determination of the local stress states in the zones where high stress gradients occur: supports, points where load are applied, geometric discontinuities, junctions etc. In this paper the authors propose a methodology for the geometric and constructive optimization of the junctions in structures made from laminated composite materials. On the other hand due to the fact that the apparition of discotinuities in structures could lead to macro failures of the continuum, the modelling and analysis of discontinuities can be made using techniques adequate for local problems, such as sub structuring and sub modeling and the use of finite element method. Consequently, the purpose of this paper is to underline the importance of the study of discontinuities in mechanical structures and to present a methodology of approach (one of the many that can be used).