Significance of distortion in thin-walled closed beam section design

Torsional and/or bending rigidities have been used as the key performance measure in conventional beam section design practice. The goal of this investigation is, however, to show that a so-called distortional rigidity also affects significantly the section shapes especially in the design of thin-walled closed beam sections. Though several investigations have analyzed complicated deformations of thin-walled beams such as distortion and warping, this paper is perhaps the first report to show how the design of thin-walled beam section shapes is affected by the additional consideration of the distortional rigidity. To illustrate this, several beam section optimization problems are considered. (C) 2002 Elsevier Science Ltd. All rights reserved.