It is well known that voids and environmental conditions may affect the strength of composite laminates. Despite the fact that voids facilitate moisture absorption, the effect of voids on the composite laminates in the presence of moisture has not been addressed in the literature. Moreover, most of the attention has been focused on composites made of unidirectional carbon-epoxy prepreg tape. This article presents experimental results on the combined effect of voids and moisture in polymer composites. The experiments consider two types of reinforcement (eight harness satin fabric and unidirectional tape), two types of resin systems (epoxy and bismaleimide), and two types of loading (interlaminar shear and compression). The effect of these factors on the fracture parameters of laminates with and without environmental conditioning is discussed.
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