Deflections of Framed-Tube Structures

In two earlier papers a simplified method was presented for the analysis of the stress distribution in framed-tube structures subjected to bending and torsion. By replacing the discrete structure by an equivalent orthotropic tube, and making simplifying assumptions regarding the stress distributions in the structure, simple closed-form solutions were achieved, and design curves presented, for three standard load cases. Provision was made in the analysis for the inclusion of individual corner columns, since in many practical situations these are considerably stiffer than the others. The object of this note is to complete the analysis by developing corresponding formulas for the horizontal and vertical deflections, and the rotations, of a framed-tube structure subjected to standard bending and torsion load cases.