ABSTRACT
Flexural-torsional buckling depends on many parameters, including those defining the structural geometry, the support and restraint conditions, the material properties, and the load arrangement. This chapter presents the energy method for the analysis of flexural-torsional buckling in a form which is suitable for hand use. It demonstrates the energy method and discusses its accuracy. The chapter considers the choice of suitable buckled shapes. The buckled shape guessed should satisfy the kinematic boundary conditions, as shapes which ignore geometrical constraints are likely to lead to buckling load predictions which are much lower than the true buckling load. The energy method gives a buckling load solution which is more accurate than the buckled shape guessed, provided this is reasonably close to the true buckled shape. This is because the energy method always provides an upper bound to the true buckling load when the guessed buckled shape satisfies at least the kinematic boundary conditions.
