On the Interlaminar Shear Stress Response for E-Glass/Epoxy Composite

Abstract

An analytical and experimental investigation was performed to study the interlaminar shear response of laminated composite material. The main objective of this study is to determine the effect of the stacking sequences and the thickness of the layers on the interlaminar shear strength of E-glass/epoxy laminated composite tubular struts which will be used in superconducting magnetic energy storage. The experimental results showed that the first ply failures always happens at the middle section of the sample and the maximum interlaminar shear stress has its maximum along the neutral axis. The absence of plies perpendicular to the 10 direction are favorable for a good stress distribution. On the other hand these plies are very important to prevent the brooming under compression loads. The results also showed that the stress distribution, due to less thick and more 10 layers were better and gave a higher interlaminar shear strength. The interfaces between the 84 layer and 10 layer are the most probable locations to start interlaminar shear failure, that is because of the large mismatch in engineering properties between these layers. The experimental results and the corresponding analytical calculations are in good agreement.

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