Optimal design of high-rise steel structures using special moment frames and bracing systems under dynamic wind and seismic loads

This study presents an optimization framework for designing a 50-storey steel high-rise building subjected to dynamic wind and seismic loading. The goal is to minimize total structural weight while meeting code-based limits on drift, displacement, stress, panel-zone shear and strong column–weak beam behaviour. A discrete special relativity search (DSRS) algorithm is introduced by mapping continuous special relativity search update rules into a discrete selection scheme and adding adaptive coefficients to improve convergence. The algorithm is integrated with SAP2000 to perform nonlinear dynamic analyses, with constraint violations addressed through a penalty-based fitness function. The optimized design achieves a minimum weight of 2.93 × 106 kg, significantly lower than the initial configuration. Statistical evaluation over 3000 function calls yields mean, median and worst solutions of 6.42 × 106, 6.59 × 106 and 7.86 × 106 kg, demonstrating efficiency. Stress-ratio and drift checks confirm compliance with AISC 360-16 and Iranian Standard 2800, indicating that DSRS is effective for discrete structural optimization.