Analyzing elastic properties of sandwich panels with cellular cores made of composite laminates

Sandwich panels are lightweight structures with good bending stiffness and because of this, have found applications in auto and aerial industries and usually are made in the form of cellular cores. They can be approximated by a homogeneous anisotropic media to a very good extent. Up to now, the panels have been made of isotropic materials but recently, FRP cores have been brought into attention. A comprehensive knowledge of the elastic properties of the panel would be necessary. In this work, the stiffness matrix for each panel and the strain energy for that is obtained. Next, a homogenization procedure based on energy is utilized to get the elastic properties. By applying certain remote strain components, and solving the equations of equilibrium for the representative volume element (RVE) along with consistency constraints, the deformation of each cell wall and from that the total strain energy of the RVE is obtained. By equating this energy to that of the idealized material, the desired elasticity constants for the homogenized panel are obtained. By altering several parameters such as orientation of remote strain and geometry of the cell, the variation of elastic constants is investigated. Some numerical results of this type are presented.

Keywords:

stiffness , sandwich structure , cellular core , composite panel