Analysis of Lateral Torsional Buckling of Steel I-Beams within Preflexed Beams in Pre-Bending Stage

In order to study the lateral torsional buckling (LTB) law of steel I-beams within preflexed beams in pre-bending stage, the traditional Rayleigh Ritz method was applied, and the modified Rayleigh Ritz method was proposed by considering the restraint effects caused by lateral braces. A large number of finite element models were established by ABAQUS. The theoretical and simulation results show that the modified Rayleigh Ritz method proposed in this paper can reduce the maximum relative error of traditional Rayleigh Ritz method by about 13%. The effects of different parameters on the LTB of steel I-beams were obtained through parameter analysis. The study in this paper can provide reference value for the analysis of LTB of steel I- beams and the parameter selection of preflexed beams in pre-bending stage.