Reza Siami Kaleybar - Master’s Student, Department of Civil and Environmental Engineering, Amirkabir University of Technology, Tehran, Iran
Sahand Sartipi - Master’s Student, Department of Civil and Environmental Engineering, Amirkabir University of Technology, Tehran, Iran
Payam Tehrani - Assistant Professor, Department of Civil and Environmental Engineering, Amirkabir University of Technology, Tehran, Iran

In the recent years, architectural advances in buildings has resulted in construction of structurally irregular buildings. Herein, a numerical study on effects of single side setback in steel moment frames is presented. SAP software was utilized in numerical modeling of these structures. The structures are analyzed under simultaneous actions of two orthogonal ground motions. Variation of shear demands in members is also studied. Comparisons are made between results of setback and full frame structures. In addition, results obtained from different methods of analysis including linear static analysis, response spectrum analysis and inelastic time history analysis are compared for the case of such structures with different setback configurations. The effects of area ratio and height ratio of setback on shear demand are also discussed. Recommendations are made to ensure uniform distribution of shear demands and consistency of related actions

Setback, Steel moment frames, Irregular building, Nonlinear analysis