Buckling analysis of open-section beams with thin-walled functionally graded materials along the contour direction

The buckling and lateral buckling of thin-walled functionally graded (FG) open-section beams with various types of material distributions are studied. The approach is based on assumption that the volume fraction of particles varies through the contour direction according to a power law. The governing buckling equation and a finite element method have been developed to formulate the problem. 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 channel-section with arbitrary distributions of material. The lateral buckling parameter and mechanism are expressed for thin-walled FG mono-symmetric I-section beam under uniformly distributed load and pure bending with several types of material distributions. For the validity of the proposed theory, the number comparisons are compared with those of formerly published work. The effects of the material distribution, load height and span-to-height on the buckling characteristics are examined in detail and highlighted. •The material properties are graded through the contour direction by the power law distribution of volume fraction.•The flexural-torsional buckling and lateral buckling of thin-walled functionally graded open-section beams are discussed.•Governing buckling equations and finite element formulation have been developed.•Impact of material distributions, load height and span-to-height ratio on buckling characteristics are studied.