Elastic Stability of Beam-Columns with Flexural Connections under Various Conservative End Axial Forces

Abstract

Stability criteria that evaluate the elastic critical axial load of beam-columns with flexural connections under the combination of conservative end axial forces are presented in a classical manner. The end axial loads include gravity loads combined with forces such as those produced by tension cables that always pass through fixed points or forces applied by rigid links. The proposed method follows the same format and classification of beam-columns and frames under gravity loads. The derived equations that can be applied to the stability analysis of beam-columns in structural and mechanical systems with rigid, semirigid, and hinged end connections overcome the limitations of current methods of stability analysis (such as the well-known alignment charts for braced and unbraced columns and frames under gravity loads). Several examples are presented in detail that demonstrate the effects of compressive forces applied by prestressed cables or rigid links combined with gravity loads on the overall stability of frames and the effectiveness of the proposed stability equations.