Flexural-torsional stability of thin-walled functionally graded open-section beams

This paper aims to present the flexural, torsional and flexural-torsional buckling of axially loaded thin-walled functionally graded (FG) open-section beams with various types of material distributions. Properties of metal-ceramic materials are described by a monotonic function of volume fraction of particles that varying across blade thickness according to a power law. The problem is formulated by using a two-noded 14-degree-of-freedom beam element. Governing buckling equations has been developed. Warping of cross-section and all the structural coupling coming from anisotropy of material are taken into account in this study. The critical load is obtained for thin-walled FG mono-symmetric I- and channel-sections with arbitrary distributions of material. As a special case, a numerical comparison is carried out to show the validity of the proposed theory with available results in the literature. In addition, effects of gradual law, ceramic core and skin, span-to-height on the buckling parameters of an axially loaded thin-walled FG open-section beam are also investigated.