# Fast and accurate elastic analysis of laminated composite plates via isogeometric collocation and an equilibrium-based stress recovery approach

## TL;DR

This paper presents a fast, accurate method for analyzing laminated composite plates using isogeometric collocation combined with an equilibrium-based stress recovery, achieving high accuracy with reduced computational effort.

## Contribution

It introduces a novel combined approach of isogeometric collocation and equilibrium-based stress recovery for laminated plates, improving efficiency and accuracy over traditional methods.

## Key findings

- High order convergence rates achieved
- Accurate displacement and in-plane stress results
- Effective out-of-plane stress recovery with minimal collocation points

## Abstract

A novel approach which combines isogeometric collocation and an equilibrium-based stress recovery technique is applied to analyze laminated composite plates. Isogeometric collocation is an appealing strong form alternative to standard Galerkin approaches, able to achieve high order convergence rates coupled with a significantly reduced computational cost. Laminated composite plates are herein conveniently modeled considering only one element through the thickness with homogenized material properties. This guarantees accurate results in terms of displacements and in-plane stress components. To recover an accurate out-of-plane stress state, equilibrium is imposed in strong form as a post-processing correction step, which requires the shape functions to be highly continuous. This continuity demand is fully granted by isogeometric analysis properties, and excellent results are obtained using a minimal number of collocation points per direction, particularly for increasing values of length-to-thickness plate ratio and number of layers.