HIGH-ORDER BENDING OF SANDWICH PANELS WITH A TRANSVERSELY FLEXIBLE CORE

摘要

A general, high-order theory for the bending behavior of a sandwich panel with a "soft" core, i.e. flexible in the vertical direction, based on variational principles is presented. The theory embodies a general rigorous and systematic approach to the analysis of plates having high-order effects owing to the non-linear patterns of the longitudinal, the transverse and the vertical deformations of the core through its height. As such it improves on the available classical and high-order theories. The formulation details the governing equations and the associated boundary conditions. Panel construction consists of upper and lower skin, metallic or composite laminated symmetric, with non-identical mechanical and geometrical properties and a "soft" core made of foam or aramid honeycomb. The formulation uses a classical plate theory for the skins and a three-dimensional elasticity theory for the core. The behavior is presented in terms of internal resultants and displacements in skins, peeling and shear stresses in skin-core interfaces, and stress and displacement fields in the core, even in the vicinity of concentrated loads. The analysis is applicable to any type of loading, distributed or concentrated, and it distinguishes between loads applied at the upper or at the lower skin. It deals with any type of boundary conditions including different conditions at the same section for the upper and the lower skins since these conditions are separately fulfilled for each skin-panel at a specified section. A simply-supported panel subjected to uniformly distributed and a concentrated load with identical skins is studied analytically and numerically.