Isogeometric Analysis of Composite Sandwich Plates Using Equilibrium-Based Stress Recovery Procedure

Abstract

AbstractComposite sandwich plates consist of a core and face sheets on the top and bottom. Accurate determination of three-dimensional stress states in sandwich plates by numerical approach requires the adoption of 3D finite element (FE) modeling or FE modeling based on layer-wise theories. Though both these numerical approaches give accurate results, they are computationally expensive. This study introduces an equilibrium-based stress recovery approach for determining three-dimensional stress state in composite sandwich plates subjected to transverse loading. This numerical approach is a two-part process, with the initial step based on the concept adopted by layer-wise theories, and the second step is a post-processing procedure. For approximating the unknown field variables, this computational approach employs non-uniform rational B-splines (NURBS). NURBS functions offer the flexibility of a higher degree of inter-element continuity. The study has adopted numerical examples based on the bending of sandwich plates under a sinusoidal load and an evenly distributed load with different edge conditions. Results obtained were compared with the 3D FE method and layer-wise theories and were found to be accurate. In comparison to the 3D FE method and the layer-wise approach, the study reveals that the proposed strategy can provide correct findings with a substantially lesser number of degrees of freedom.KeywordsIsogeometric Galerkin methodNURBSSandwich platesPost-processingEffective stress recovery approachSingle-element approach