Progressive failure analysis of filament wound composite tubes under internal pressure

Complete understanding of the multiple complex failure mechanisms of high performance tubular composite structures is mandatory to enable implementation of more reliable failure and damage models to predict their mechanical behavior. These structures present non-linear behavior because their failure occurs by means of a progressive series of events, and their catastrophic failure rarely occurs at the first-ply failure load. This study aims at presenting a damage model based on progressive failure analysis to evaluate the mechanical response of composite tubes subjected to hydrostatic internal pressure load. Composite tubes wound at ±55° have the highest burst pressure and radial deformation resistances, and the addition of a hoop layer harmed the mechanical performance of the tube. All tubes tested failed in the matrix by tensile transverse stresses and in-plane shear, once the shear stresses increase up to winding angle of ±55°, decreasing for higher angles, where transverse stresses dominate the failure mode.