Comparative Study of Outrigger and Wall-Frame Structural Systems in Steel–Concrete Composite Tall Buildings

IS 16700: 2017—Criteria for structural safety of tall concrete buildings recommend different structural systems for 50–250 m tall buildings with a 4–10 slenderness ratio. Outriggers and belt truss system are popular in of structural systems, outriggers reduce lateral displacement and increase bending stiffness of the buildings. This paper evaluates performance of outrigger structural systems in steel–concrete composite tall buildings compared to wall-frame structural systems. The typical floor plan dimensions of the tall buildings studied are 48 m x 48 m, with the stories ranging from 24, 44, and 64. One outrigger is provided at the mid-height and modeling and analysis of tall buildings are performed. The comparison of natural time period, base shear, displacement and inter-story drift for both structural systems is presented. It is advisable to investigate the optimum location of outrigger in outrigger structural systems. In conclusion, as building height grows, outrigger systems perform better compared to wall-frame system in resisting lateral loads.