First-ply failure prediction of an unsymmetrical laminated ellipsoidal woven GFRP composite shell with incorporated surface-bounded sensors and internally pressurized

Abstract

First-ply failure of an unsymmetrical laminated ellipsoidal woven Glass Fiber Reinforced Polymer (GFRP) composite shell internally pressurized was investigated analytically using the linear interpolation technique. The shell's boundary was fixed at its end. Tsai-Wu failure criterion was used as the composite failure design factor. The analytical results, including critical internal pressure and strains in global directions, were validated with the experimental results for some arbitrarily selected points on the shell surface along meridian axis. Manufacturing of laminated ellipsoidal composite shells was performed by using the Vacuum Infusion Process (VIP), a novel method commonly adopted for the fabrication of laminated composite shells. Surface-bounded sensors were installed on the shells' surface to measure the strain values after the internal pressure was applied. According to the analytical investigation findings, the failure factor was critical at the innermost ply. In addition, for each ply, the shell's edge was observed to be the region with the highest failure factor. The experimental findings confirmed that the failure occurred in the regions close to the shell's edge, as predicated by the analytical approach. The results from both approaches were in a close agreement. Subsequently, the effect of various parameters including thickness, aspect ratio, and stacking sequence on the first-ply failure of laminated ellipsoidal woven GFRP composite shell were investigated and the critical mechanical factors to avoid failure were determined.