Sandwich-structured composite

About: Sandwich-structured composite is a research topic. Over the lifetime, 5853 publications have been published within this topic receiving 101126 citations.

Nonlinear Behavior of Sandwich Panels with a Transversely Flexible Core

Abstract: Nonlinear behavior of sandwich panels with a transversely flexible core is presented. The study is based on a highorder nonlinear formulation that includes the influence of the transverse flexibility and shear resistance of the core on the panel behavior, thus allowing for interaction between the facings through the core thickness. The solutions obtained are general and are not based on decoupling of the local and global responses as commonly used in the literature. The governing equations along with the appropriate boundary and continuity conditions are presented, and the solution approach is outlined. The path-following algorithm devised is based on the natural parameter and the arc-length continuation techniques. The example problems discussed include a concentrated line load exerted at midspan of the panel, couples applied at the panel edges, and compression of an asymmetric sandwich panel. Mode interaction observed in the panel behavior is shown to be a result of the flexibility of the "soft" core. Variations in the boundary conditions of the sandwich panel as well as in the layout of the compressive longitudinal loads are also shown to shift its response from an imperfection-sensitive to an imperfection-nonsensitive one and vice versa.

An axisymmetric elastic analysis for circular sandwich panels with functionally graded cores

Abstract: This paper presents an analytical solution in the framework of the elasticity theory, which is useful in describing the elastic bending response of axisymmetric circular sandwich panels with functionally graded material cores and homogeneous face-sheets. The Young’s modulus of the core is assumed to be exponentially dependant on the transverse direction and the Poisson’s ratio as well as uniform and equal to the face-sheets ratio. The elastic solution is obtained using a Plevako representation, which reduces the problem to the search of potential functions satisfying linear fourth-order partial differential equations. We explicitly obtain the analytical solution by writing the potential functions as Fourier Bessel expansions with respect to the radial coordinate. A comparative study of functionally graded versus a homogeneous sandwich core is presented by considering the first term of the expansion as the loading condition. In this way, the solution is written in a closed form and furnishes a benchmark to accurately investigate the agreement with the structural theory results.