Lateral-torsional buckling capacity of beams with web openings or varying cross-sections: An analytical approach

Abstract

An analytical approach is proposed in this paper to predict the lateral-torsional buckling capacity of beams with web openings, such as cellular beams and castellated beams, and those with varying cross-sections (i.e. sudden change of cross sections) along their length. The approach consists of a new formula for elastic critical moment for lateral-torsional buckling of the beam, derived in this paper using the energy method. The concept revolves around the equivalence of the strain energy stored in a member during lateral torsional buckling to the overall work done by the external loads on the beam. This formula is employed to determine the non-dimensional slenderness, thereby establishing the design capacities for lateral-torsional buckling moments in beams with web openings and varying cross-sections. The proposed approach’s accuracy is validated by comparing experimental and numerical buckling capacities of beams with web openings and patched-corroded steel beams respectively. The comparison reveals a good agreement between the capacities, confirming the accuracy of the derived formula and the proposed approach.

Publication
Book of Abstracts of the 3rd International Symposium on Risk Analysis and Safety of Complex Structures