Comparative Seismic Performance Analysis of a RC Building in the Four Seismic Zones of Bangladesh Using ETABS 2022 Based on BNBC 2020

Abstract

Bangladesh is located in a seismically active region, making the seismic design of reinforced concrete (RC) structures a critical concern for structural safety and resilience. This study presents a comparative seismic performance analysis of a typical (G+M+08) residential RC building across all four seismic zones of Bangladesh as defined in the Bangladesh National Building Code 2020 (BNBC 2020). The building was modeled and analyzed using ETABS 2022 software under equivalent static analysis method. Seismic zone parameters and wind loads were applied for four representative locations: Jessore (Zone-1), Rajbari (Zone-2), Tangail (Zone-3), and Sylhet (Zone-4). Key structural responses—including story displacement, inter-story drift, base shear, and lateral stiffness—were evaluated and compared across zones. Results indicate that seismic demands increase progressively from Zone-1 to Zone-4, with Sylhet (Zone-4) showing the highest values in displacement and base shear. The study also examines the performance of different framing systems—OMRF, IMRF, and SMRF—under zone-specific loading conditions. The findings emphasize the importance of zone-specific design approaches and the adoption of appropriate lateral load-resisting systems to ensure earthquake-resistant construction in Bangladesh. All structural drawings were prepared using AutoCAD for accuracy and compliance with design standards.