Plastic Collapse Analysis of T-Beams under Bending

Abstract

This paper presents a numerical study of the response and stability of elastic-plastic T-beams subjected to pure bending with the tip of the web in compression. The moment-curvature response of such beams is characterized by a limit moment instability. The mode of collapse depends on the slenderness of the beam. The objective of the study was to make detailed comparisons with experimental observations of the mode of collapse and the curvature at which the limit moment developed. The predictions were generated using the finite-element code ABAQUS and compared with experimental measurements. The numerical predictions of the limit moment curvature and the mode of collapse agree very well with experimental observations, but are sensitive to the initial geometric imperfection of the beam. Therefore, it is important to carefully consider the effects of initial imperfections corresponding to the lateral-torsional and local collapse modes in the calculation of the limit moment instability, especially for short beams.