Analysis of Laminated Soft Core Sandwich Plate Having Interfacial Imperfections by an Efficient C0 FE Model

An efficient C0 continuous two dimensional (2D) finite element (FE) model is developed based on a refined higher order shear deformation theory (RHSDT) for the static analysis of soft core sandwich plate having imperfections at the layer interfaces. In this (RHSDT) theory, the in-plane displacement field for the face sheets and the core is obtained by superposing a globally varying cubic displacement field on a zig-zag linearly varying displacement field. The transverse displacement is assumed to have a quadratic variation within the core and it remains constant in the faces beyond the core. In this theory, the interfacial imperfection is represented by a liner spring-layer model. The proposed model satisfies the condition of transverse shear stress continuity at the layer interfaces and the zero transverse shear stress condition at the top and bottom of the sandwich plate. The nodal field variables are chosen in an efficient manner to circumvent the problem of C1 continuity requirement of the transverse displacements associated with the RHSDT. The proposed model is implemented to analyze the laminated composites and sandwich plates having interfacial imperfection. Many new results are also presented which should be useful for the future research.