Effect of Ply-Level Material Uncertainty on Composite Elastic Couplings in Laminated Plates

Abstract

Elastic couplings can strongly effect the structural behavior of composites by their presence or absence. We show that uncertainties in composite material properties at the ply-level can lead to undesirable couplings in laminates designed with no couplings. Moreover, uncertainty can alter the couplings in lay-ups where couplings are introduced deliberately for structural or aeroelastic tailoring. For numerical results, a symmetric balanced and an unsymmetric unbalanced laminate are considered. Material uncertainties are numerically quantified using Monte Carlo simulations for different number of plies, ply angles, and loading conditions and their effect is found to be substantial.

Keywords:

• Material Uncertainty
• Composite
• Monte Carlo Simulation
• Aeroelastic Tailoring
• Coupling

Acknowledgments

The authors thank Dr. Om Prakash from Boeing for suggesting the possibility of ply-level uncertainty in composite materials.