Analysis of transverse cracking and stiffness loss in cross-ply laminates with hygrothermal conditions

The change in longitudinal modulus as a result of transverse ply cracking in simple cross-ply laminate is examined theoretically with the taking into consideration the decrease of the mechanical properties of material by the variation of temperature and moisture. The results show that the hygrothermal environment has a significant effect on the relative reduction of longitudinal Young’s modulus at the higher crack density, in contrast with the complete reduction of longitudinal Young’s modulus in which the sensitivity of the hygrothermal effects become weaker but significant at the lower crack density.