Optimal outrigger locations of double-pure-outrigger systems and combined energy-dissipating outrigger systems under seismic loads

Abstract

This paper investigates the optimal outrigger locations of double-pure-outrigger systems and combined energy-dissipating outrigger systems in high-rise buildings subject to seismic load. Five types of double-outrigger systems are considered. This paper proposes simplified models for these double-outrigger systems under seismic load. The models are developed using the complex mode superposition response spectrum method for peak seismic responses. Based on parameter analyses, this paper defines dimensionless parameters to characterize each of the double-outrigger systems. Power function models are developed to define the optimal outrigger locations of the pair of outriggers as functions of such dimensionless parameters. From the perspective of three target responses, the optimal locations of the pair of outriggers targeting the base moment are the largest, and the ones targeting the top displacement and the inter-story drift have slight differences, but generally, the former ones are larger than the latter ones.