Hygrothermal Effect in [θm/90n]s Cracked Composite Laminates – Desorption Case

Two analytical approaches were used to predict the effect of transverse cracks on the stiffness degradation, Shear-lag model and variational approach for [θm/90n]s composite laminates and under different environmental conditions by the variation of temperature and transient moisture concentration distribution in desorption case. Good agreement is obtained by comparing the prediction models and experimental data published by Joffe. Furthermore the cracked angle-ply laminate is submitted to hygrothermal conditions. The transient and non-uniform moisture concentration distribution gives rise to the transient relative reduction of the longitudinal Young's modulus. The obtained results represent well the dependence of the stiffness degradation on the cracks density, fibre orientation angle of the outer layers and transient hygrothermal conditions.