Seismic Resilience and Safety of Step-Back and Set-Back RC Frame Buildings on Sloping Ground: A Comparative Study of Vulnerability

This study investigates the seismic resilience and safety of reinforced concrete (RC) frame buildings with Step-Back (SB) and Step-Back Set-Back (SBSB) configurations on sloping ground. The research evaluates the impact of varying slope angles (10°, 19°, 27°, and 35°) on the seismic performance of five-storied RC buildings using both static and dynamic analyses, following the guidelines of NBC 105:2020. A total of 24 analytical models were developed using ETABS to compare the seismic vulnerability of SB and SBSB configurations, with and without shear walls. The results indicate that SBSB configurations with mid-span shear walls exhibit superior seismic performance, significantly reducing story displacements, inter-story drift, and peak floor acceleration compared to SB configurations. The study highlights the importance of shear wall placement in enhancing seismic resilience, particularly in buildings on steep slopes. Design recommendations are provided to optimize seismic safety in sloped regions, emphasizing the need for careful structural planning in earthquake-prone areas