Seismic Behavior Study of RCC Structures with Different Shapes in Zone III Using ETABS

Earthquakes impose lateral forces on structures that often lead to severe damage and collapse, especially in seismically active regions. The geometry of a building significantly influences its seismic response due to the variation in mass distribution and stiffness. This study investigates the seismic performance of three Reinforced Cement Concrete (RCC) buildings with different shapes Square (Commercial), Rectangular (Residential), and Hollow-Rectangular (Educational) located in Seismic Zone III. All buildings were modelled and analyzed in ETABS using identical loading conditions, storey heights, and material properties to assure uniform comparison. The seismic responses including storey displacement, storey drift, and shear deformation were evaluated as per IS 1893:2016. Results indicate that shape configuration plays a crucial role in structural behaviour. The square-shaped building showed the least displacement due to uniform stiffness, whereas the hollow-rectangular structure exhibited the highest deformation because of stiffness discontinuity and torsional effects. The findings emphasize the importance of geometric planning in enhancing seismic resistance and minimizing structural damage.