Seismic performance comparison of symmetrical and asymmetrical low-, mid-, and high-rise Rc structures: a height-based evaluation of structural behavior and material efficiency

Abstract

This study investigates the seismic performance of twelve reinforced concrete (RC) building configurations—categorized as symmetrical and asymmetrical forms across low-, mid-, and high-rise heights—using STAAD.Pro simulation in compliance with IS 1893:2016. The models include rectangular, cross-plus (symmetrical), T-shape, and U-shape (asymmetrical) plans, each evaluated under consistent material and geometric parameters. Key seismic performance indicators such as natural time period, base shear, maximum storey drift, lateral displacement, plate stress, and structural material usage were analyzed. The study reveals that asymmetrical buildings consistently exhibit higher drift, displacement, and internal forces compared to their symmetrical counterparts, especially in higher-rise configurations. A comprehensive material efficiency evaluation also indicates that asymmetrical structures consume significantly more concrete and steel to meet stability requirements. Statistical validation through two-sample t-tests confirms that these performance differences are significant (p < 0.05). Additionally, consolidated performance trends across heights highlight a nonlinear escalation of seismic demands with building height and asymmetry. The findings emphasize the necessity of incorporating symmetry and compact plan geometries into seismic design to enhance performance and material efficiency. This research contributes practical insights for structural engineers and urban planners in optimizing RC building configurations for earthquake-prone regions.