Homogenization of V-pattern Folded Core Sandwich Panels Using Finite Element Simulations

A finite element based homogenization approach is presented and adopted to predict the equivalent stiffness properties for V-pattern folded core sandwich panels. Due to the inherent periodic feature of the V-pattern folded core sandwich panel, one single unit cell was studied and periodic boundary conditions were imposed so as to obtain the in-plane, coupling and bending stiffness properties. Furthermore, influence of transverse shear deformation was considered. The first order shear deformation theory was used together with a finite element simulation for a three-dimensional (3-D) folded core sandwich beam model to derive the transverse shear stiffness. Then a comparative study between the detailed 3-D V-pattern folded core sandwich panel and corresponding two-dimensional (2-D) equivalent plate model was performed and the deflection results were compared. The results show that the transverse shear influence should not be neglected for a V-pattern folded core sandwich panel subjected to a transverse load. The homogenized 2-D plate model predicts deformations with satisfactory accuracy when the transverse shear stiffness is included.