This study is all about the presentation of the results of the analyses made to determine the inelastic lateral torsional buckling strength of singly symmetric singly stepped I-beam with constant depth subjected to basic loading condition. A finite element program ABAQUS and a regression program MINITAB are used to analyze the simply supported singly symmetric singly stepped I-beams having singly symmetric ratio, ρ, of 0.1 to 0.9 and a Lb/h ratio of 4.5. Using the results of the analyses made, a design equation is suggested that can easily calculate the stepped beam correction factor Cist which then can be used to determine the inelastic lateral torsional buckling strength of singly symmetric singly stepped I-beams subjected to pure bending moment. Then, the results from the equation proposed are compared with the results obtained from the finite element analysis. The results obtained show acceptable results for singly stepped beams having a ρ of 0.3 to 0.9 and a very conservative result for a ρ of 0.1.

ABSTRACT
 1. Introduction
 2. Background and Previous Studies
 3. Finite element modeling
 4. Finite Element Results
 5. Conclusions
 References

• Albert Surla(Dept of Civil Engineering, Sangmyung University)
• Kathleen Mae Gelera(Dept of Civil Engineering, Sangmyung University)
• Jong Sup Park(Associate Professor, Dept of Civil Engineering, Sangmyung University)
• Gyu Sei Yi(Dept of Civil Engineering, Sunmoon University)