Elastic buckling and static bending of shear deformable functionally graded porous beam

摘要

This paper presents the elastic buckling and static bending analysis of shear deformable functionally graded (FG) porous beams based on the Timoshenko beam theory. The elasticity moduli and mass density of porous composites are assumed to be graded in the thickness direction according to two different distribution patterns. The open-cell metal foam provides a typical mechanical feature for this study to determine the relationship between coefficients of density and porosity. The partial differential equation system governing the buckling and bending behavior of porous beams is derived based on the Hamilton's principle. The Ritz method is employed to obtain the critical buckling loads and transverse bending deflections, where the trial functions take the form of simple algebraic polynomials. Four different boundary conditions are considered in the paper. A parametric study is carried out to investigate the effects of porosity coefficient and slenderness ratio on the buckling and bending characteristics of porous beams. The influence of varying porosity distributions on the structural performance is highlighted to shed important insights into the porosity design to achieve improved buckling resistance and bending behavior. (C) 2015 Elsevier Ltd. All rights reserved.