Analysis of multi-layered filament-wound composite pipes under internal pressure

Composite pipes in this study are composed of multi-layered filament-wound (FW) structures. Each layer of the pipes is assumed to be anisotropy. Based on the three-dimensional (3-D) anisotropic elasticity, an exact elastic solution for stresses and deformations of the pipes under internal pressure is presented. Moreover, detailed stress and strain distributions for three given angle-ply pipe designs are investigated by using the present theory. The shear extension coupling is also considered because the lay-up angles with + φ and − φ layers cannot exist in the same radius. For cylindrical-pressure vessels with different angle-ply pipe, the ratio of applied hoop-to-axial stress in each layer is different. Even if quite a thin-walled pipe, the ratio of hoop-to-axial stress is no longer a constant of 2:1.