Mechanical Behavior of GFRP Laminated Composite Pipe Subjected to Uniform Radial Patch Load

Cylindrical vessels are widely used for storage and transportation of fluids. Using composites shells can improve the corrosion resistance of the product and reduce weight therefore investigation of the mechanical behavior is important. For this purpose cylinders with 6, 12 and18-ply of GFRP , with symmetric ply sequence of [90/0/90]s, [90/0/90/0/90/0]s and, [90/0/90/0/90/0/90 /0/90]s with layer thickness 1.3 mm and mean radius 250 mm, are considered under uniform radial patch load. The analysis was based on the shell theory and classical mechanics of laminated composites. A code was written using MATLAB software to compute stress and deflection of the cylinder shell. In numerical simulation, each unidirectional composite ply is treated as an equivalent elastic and orthotropic panel. Analysis is focused on the area of cylinder where the patch load is applied. The results show that the analytical prediction compares well with numerical responses of previous literature. The procedure can be used to predict maximum stress and displacement in a multi-layer shell for various types of similar loading.