Seismic Optimization of Buckling-Restrained Brace Locations in RC Portals with Partial Shear Walls via Genetic and Harmony Search Algorithms Taufiq Ilham Maulana, Athaya Hasna Fauzia, Sayed Qudratullah Sharafi, Besty Afriandini, Muhammad Ibnu Syamsi, Sekar Ayu Mustika Jati, Saznizam Sazmee Sinoh
1 Civil Engineering Study Program, Faculty of Engineering, Universitas Muhammadiyah Yogyakarta, Bantul, Indonesia
2 Department of Architecture and Civil Engineering, Toyohashi University of Technology, Toyohashi, Japan
3 Department of Civil Engineering, Faculty of Engineering, Universitas Muhammadiyah Purwokerto, Purwokerto, Indonesia
4 Research Fellow, Universitas Muhammadiyah Yogyakarta, Yogyakarta, Indonesia
5 Department of Civil Engineering, Faculty of Engineering, Universiti Malaya, Malaysia
Abstract
Shear walls are commonly used in reinforced concrete buildings to enhance lateral stiffness and seismic resistance. However, in mid- to high-rise structures, their effectiveness diminishes in upper stories due to the concentration of bending demands and deformation, particularly when shear walls are curtailed below full height. This configuration can lead to excessive displacements in upper floors during strong earthquakes. To address this issue, this study investigates the integration of buckling-restrained braces (BRBs) in the upper frames of buildings with curtailed shear walls to improve seismic performance. The objective is to identify the optimal BRB placement strategy to mitigate upper-story deformations while maintaining structural efficiency. Numerical modeling was conducted on mid- and high-rise reinforced concrete frames incorporating partial shear walls, and seismic analysis was carried out using nonlinear dynamic simulations. Two metaheuristic optimization techniques, namely Genetic Algorithm (GA) and Harmony Search Algorithm (HSA), were applied to determine the most effective BRB configurations, as they are well-suited for solving complex, nonlinear structural optimization problems. The results indicate that BRB placement significantly enhances the structural response under seismic loading, particularly in the upper stories where shear walls are absent. Among the two algorithms, GA demonstrated greater computational efficiency and effectiveness in identifying optimal brace locations. These findings support the use of BRBs as a supplemental system in buildings with curtailed shear walls and highlight the potential of evolutionary algorithms in optimizing seismic design solutions.
