Sandwich panel

About: Sandwich panel is a research topic. Over the lifetime, 4665 publications have been published within this topic receiving 49812 citations.

The Through-Thickness Compressive Strength of a Composite Sandwich Panel With a Hierarchical Square Honeycomb Sandwich Core

Abstract: Sandwich panels with aluminum alloy face sheets and a hierarchical composite square honeycomb core have been manufactured and tested in out-of-plane compression. The prismatic direction of the square honeycomb is aligned with the normal of the overall sandwich panel. The cell walls of the honeycomb comprise sandwich plates made from glass fiber/epoxy composite faces and a polymethacrylimide foam core. Analytical models are presented for the compressive strength based on three possible collapse mechanisms: elastic buckling of the sandwich walls of the honeycomb, elastic wrinkling, and plastic microbuckling of the faces of the honeycomb. Finite element calculations confirm the validity of the analytical expressions for the perfect structure, but in order for the finite element simulations to achieve close agreement with the measured strengths it is necessary to include geometric imperfections in the simulations. Comparison of the compressive strength of the hierarchical honeycombs with that of monolithic composite cores shows a substantial increase in performance by using the hierarchical topology. DOI: 10.1115/1.3086436

Building panel, manufacturing method and panel assembly system

Abstract: The improved sandwich panel of the present invention includes inner and outer panel faces that have a foam core integrally bonded therebetween by the hardening and curing of a liquid foam during the manufacturing process. The faces of the preferred panel embodiments are composed of cement-fiber boards and/or cement-woodchip boards. The preferred sandwich panel has a male projecting lateral edge on one side and a female recess in the core on the opposite side edge. The preferred method of manufacturing the panels includes the installation of the male edge member prior to foaming and the utilization of edge recess forming members installed at the edges of the panel assembly prior to the insertion of liquid foam therebetween. The removal of the edge recess forming members following the curing of the foam easily creates the edge recesses. The method of construction of a structure utilizing the improved panel includes the installation of a bottom sill to a foundation or floor, the engagement of panel members to the bottom sill and to each other through the male-female side edge interconnection and the placement of a continuous top plate within the top edge recesses of the panels. Thereafter, by nailing, the assembled panels are engaged to the bottom sill, to each other through the male-female interconnection and the top sill.

A multi-scale approach for the simultaneous shape and material optimisation of sandwich panels with cellular core

Abstract: This work deals with the problem of the optimum design of a sandwich panel made of carbon-epoxy skins and a metallic cellular core. The proposed design strategy is a multi-scale numerical optimisation procedure that does not make use of any simplifying hypothesis to obtain a true global optimum configuration of the system. To face the design of the sandwich structure at both meso and macro scales, a two-level optimisation strategy is employed: at the first level the goal is the determination of the optimum shape of the unit cell of the core (meso-scale) together with the material and geometric parameters of the laminated skins (macro-scale), while at the second level the objective is the design of the skins stacking sequence (skin meso-scale) meeting the geometrical and material parameters provided by the first-level problem. The two-level strategy is founded on the polar formalism for the description of the anisotropic behaviour of the laminates, on the NURBS basis functions for representing the shape of the unit cell and on the use of a genetic algorithm as optimisation tool to perform the solution search. To prove its effectiveness, the multi-scale strategy is applied to the least-weight design of a sandwich plate subject to constraints of different nature: on the positive-definiteness of the stiffness tensor of the core, on the admissible material properties of the laminated faces, on the local buckling load of the unit cell, on the global buckling load of the panel and geometrical as well as manufacturability constraints related to the fabrication process of the cellular core.