Numerical Investigation of Different Lateral Load Resisting Systems in a 12-storied Irregular-shaped Residential Building

Bangladesh is particularly vulnerable to earthquake risks due to its position in a seismically active region. The country regularly experiences moderate tremors from neighboring areas. Irregular tall buildings are at more risk because their uneven mass distribution, asymmetric shapes, and lack of consistent stiffness can magnify seismic forces. These buildings may suffer from uneven force distribution during seismic events, leading to damage at critical points such as joints and corners. To reduce these risks, incorporating structural solutions like shear walls, bracing systems, or base isolators can improve the earthquake resistance of such buildings, enabling them to better withstand lateral forces. Shear walls and steel bracing both play vital roles in enhancing the earthquake resistance of buildings by improving their lateral stability and strength. In this research, a G+11 storied irregularly shaped RCC building is modelled and analyzed by ETABS 16 using three different structural systems: framed, framed with the shear wall, and framed with steel bracing. The analytical results have been compared by BNBC 2020. Necessary checks like the soft story, torsional irregularity, serviceability, etc. have also been performed. The research shows that the framed with share wall system has the highest resisting capability against dead loads, live loads, wind, and seismic loads. It showed minimal lateral displacement, a big concern for constructing irregularly shaped buildings. It also provided the best results in the case of torsional irregularity, soft story, and serviceability checks. The results of this study will be useful to structural engineers, architects, and urban planners who are involved in designing and constructing irregular buildings.