Prediction of Failure in Unsaturated Polyester Reinforced by Plain Weave Glass Fabric

Abstract

Polyester/glass fiber is probably by far the most commonly used composite. This paper presents the results of an investigation on the failure of this composite made with a plain weave glass fabric. A recently proposed sub-plies model is utilized to predict the failure strengths of the fabric composite after shear deformation of the interlaced yarns, induced by the forming process. A procedure for the determination of the equivalent on-axis tensile and compressive strengths of the constituent plies is also proposed to take into account the fiber undulation effect on strength performance. The predicted compressive and tensile strengths are compared with experimental measurement as a function of the deformation angle of the interlaced yarns. Furthermore, the onset of damage is also compared with the initial failure predicted by the sub-plies model. The predicted results are in good agreement with the experimental data.