Flexural-Torsional Buckling

So far, the explanations regarding the stability of slender compressed beams have been limited to flexural buckling/Euler-type buckling. However, there are other stability problems of such structures, which we denote as torsional buckling or flexural-torsional buckling, depending on the load and cross-section type. In this chapter, we want to address these stability problems, which are also extremely important in practice. We begin the discussion with a consideration of so-called torsional buckling, which is a special case of flexural-torsional buckling, before moving on to the more general case of flexural-torsional buckling of prismatic beams with arbitrary cross-sections. After the analytical treatment of elementary cases, an energetic treatment of flexural-torsional buckling is carried out and, as in the case of flexural buckling, a number of energy-based approximation methods are discussed. The chapter concludes with the investigation of beams with a fixed axis of rotation and of elastically supported beams.