Design of composite structures under cyclic loads

The first part of the paper is devoted to the presentation and discussion of various problems encountered in theoretical and numerical modelling of fatigue phenomena and failure modes in the 2-D description of composite structures. Then, a numerical FE model is proposed based on the progressive pure deterministic evaluation of the stiffness degradation of structures. Using the proposed formulation logarithmic fatigue life contours have been estimated for composite plates subjected to shear loads or tension.