DEVELOPMENT OF REGION-WISE ZIG-ZAG THEORY FOR LAMINATED STRUCTURES COMPOSED OF COMPOSITE AND ISOTROPIC MATERIALS

Abstract

 A Region-wise ZIG-ZAG theory that combines the improved ZIG-ZAG theory and the layer-wise theory is proposed. In this theory, the laminated structure is divided into several regions in the thickness direction, and the region boundary and inside of the region are given degrees of freedom. The high-order improved ZIG-ZAG theory is used to represent the ZIG-ZAG displacement inside the region. As a result, it is easy to apply to delamination analysis and to structures composed of composite and isotropic materials, and the number of unknown degrees of freedom is considerably smaller than the layer-wise theory. The accuracy and applicability of this theory are verified using numerical examples of bending analysis of anisotropic laminated and sandwich plates.