Investigation of the lateral torsional buckling of lateral bracing with thin walled I beams

In this study, lateral torsion buckling of thin walled I beams supported with lateral bracings. Thin walled I beams are stuctural members which has small torsional rigidity and big flexural rigidity. Due to those characteristics, one of the most important factors which influnce the collapse status of thin walled I beams is lateral torsional buckling.When a rectangular thin plate which has high flexural rigidiyt laterally deflects and become unstable under the effect of in planer forces. This deflections finally reach a specific load value and buckling observed.Lateral torsional buckling is observed when buckling rigidity of a beam is relatively larger than the lateral rigidity of a beam and without the lateral bracings. This buckling is observed simultaneously with the torsion.This is considered as a significantly vital in practice hence, in the condition of lateral torsional buckling, this issue should also considered in the structural design (Michell, 1899). This study which is consideres the lateral torsional buckling consist of three main chapters. In the first chapter, primarily information about the lateral torsional buckling was presented. In the second part of the study, the studies carried out, findings, and observations were presented. The lateral buckling behaviour of lateral bracing thin walled I beams analyzed in the scope of BTII theory with the aid of finite element methods. The analyzes were carried out in FRILO program. In the last part of the study, findings and suggestions related with the study were summarized. Key Words: FRILO, Thin-walled I beam, Lateral torsional buckling, Lateral brancing, Second-order Theory