Seismic Behaviour of Outrigger Braced Systems in High Rise 2-D Steel Buildings

Abstract

This paper aims to investigate the seismic behaviour of outrigger braced buildings to find out the optimum location of outrigger in high rise 2-D steel buildings. For this purpose, a nonlinear static pushover analysis was carried out on different outrigger braced high rise steel buildings of 20, 25, 30, and 35 storeys to capture the seismic response. In this study, the position of outriggers varies from a first storey to top storey in outrigger braced buildings of particular storey height. It is observed that the position of outriggers, lateral load patterns, and height of building significantly influences the seismic performance of the high rise building. The position of outriggers in high rise building significantly influences the seismic performance by increasing strength and stiffness, which are measured in terms of base shear, storey displacement, inter-storey drift ratio, and performance point. Furthermore, nonlinear static pushover analysis using different lateral load patterns points out that the optimum location of outrigger can be varied with different load patterns.