Finite Element modeling of an orthotropic laminated plate under cylindrical bending

Abstract

Assumption of plane strain is valid for the structures made of isotropic and specially orthotropic materials. In case of generally orthotropic structure though the geometry, constraints and loading are symmetrical, the material arrangement may not permit to consider as a 2D plane strain problem such as an angle-ply laminate where the fibers are oriented in the plane of the plate. In such cases 3D analysis is required. However when the third dimension is infinitely long, the problem can be modeled with a finite length plate without losing the accuracy of the result. The present investigation deals with the identification of minimum length required to model an infinitely long FRP laminated plate under cylindrical bending with two different end conditions subjected to uniform pressure using three-dimensional finite element analysis. A four-layered angle-ply laminate with symmetric and anti-symmetric arrangement is modeled in ANSYS software and the required length for two different thickness ratios (S = 10, and 50) is determined based on the variation of transverse deflection and in-plane normal stress along the span direction of the plate.