Comparing Optimized Perimeter Steel Bracing of Tall Buildings under Different Seismic Regions

Abstract

There are challenges associated with building high-rise structures sustainably and safely, especially in seismic regions. These types of structures face extreme loading conditions. One promising solution for these challenges is topology optimization, which involves determining the optimal material distribution to achieve desired performance criteria under certain constraints. However, implementing topology optimization for real-life structures under seismic design codes is challenging due to multiple nonlinear constraints, discrete variables, and high computational cost. Recently, there have been several attempts to use topology optimization for seismic design. Considered groundbreaking in this regard is research proposed by Amory Martin in 2020. This author’s work proposed a method called the sum of modal compliances to optimize a steel lateral frame system in tall buildings for seismic design. The focus of this work is to expand upon this method, generating lateral frame systems for tall buildings from response spectra in different seismic regions rather than from an idealized design spectrum. The structural performance of the various optimized framing layouts produced were further verified through a nonlinear analysis, which indicated that they had the potential to outperform traditional bracing systems under seismic excitation. This was a trend observed in multiple seismic regions in North America. This research has important implications as the use of topology optimization in designing lateral brace frames for tall buildings under seismic excitation could help develop safer and more sustainable structures, reducing embodied carbon while maximizing construction revenue.