Numerical simulations of the effects of non-uniform temperature distributions on lateral torsional buckling resistance of steel I-beams

Using a commercially available finite element analysis package ABAQUS, this paper presents the results of a numerical parametric study to investigate the effects of a number of design factors on the lateral torsional buckling bending moment resistance of a steel beam with non-uniform temperature distributions. The results of these numerical studies are then used to check the predictions of current design methods in BS 5950 Part 8 and ENV 1993-1-2. It is found that both methods predict much lower critical temperatures than ABAQUS and neither method is suitable to deal with the effects of non-uniform temperature distributions. To enable ENV 1993-1-2 to be used, it is necessary to modify the lateral torsional buckling slenderness of a steel beam to consider the effects of non-uniform temperature distributions on the elastic critical buckling resistance and the effective cross-sectional shape of the steel beam. An example is provided to show how the modified effective length may be calculated. © 2003 Elsevier Science Ltd. All rights reserved.