Comparison of Stiffness and Failure Behavior of the Laminated Grid and Orthogrid Plates

Abstract

The present paper investigates the advantages of a new class of composite grid structures over conventional grids. Thus far, a known grid structure such as orthogrid or isogrid has been used as an orthotropic layer with at most in-plane anisotropy. The present laminated grid is composed of various numbers of thin composite grid layers. The stiffness of the structure can be adjusted by choosing proper stacking sequences. This concept yields to a large variety of laminated grid configurations with different coupling effects compare to conventional grids. To illustrate the advantages of the laminated grids, the stiffness matrices and the bending response of the laminated and conventional grids are compared. Furthermore, a progressive failure analysis is implemented to compare the failure resistance of laminated and conventional grids. The results indicate that, thoughtful selection of stacking sequences of the laminated grid enhances the stiffness and response of the laminated grids without significant effect on the failure index.