Buckling of T-strut subject to compressive force on its shear center

T-struts have the peculiarity of providing larger resistance to buckling about their axis of symmetry when the compression is applied at the shear center in lieu of the centroid of the section. But this feature is not well known to designers of constructional steel. This article introduces critical load formulae, discusses the various factors affecting the capacity increase such as sectional dimensions, buckling mode, fabrication error, and decrease of in-plane capacity due to load eccentricity, and recommends taking advantage of the capacity increase in truss design by shifting the working line of a T-section compression chord to the shear center.