Effect of fiber orientation and cyclic environmental conditions on the non-mechanical residual stresses in resin matrix composite panels

Abstract EN

The main objective of this work is to study the effect of the fiber orientation on the nonmechanical residual stresses in resin matrix composite panel exposed to cyclic temperature and moisture environmental conditions during long time.

The effect of the fibers orientation is evaluated using the degree of anisotropy concept introduced from polar representation of tensors.

Various laminates of type [+θ,–θ]rs were analyzed under typical boundary conditions and the same hygrothermal loading.

The obtained results show, on the one hand that the thermal and hygroscopic stresses vary differently with the fiber orientation angle in such a way that their superposition do not lead to a growth of the intern resulting stresses, on the other hand that the state of the different stresses in the ply frame will be modified by the orientation of fibers.

These stresses have to be taken into account for the design of composite structures subjected to a moist environment.