Comparative Study on Seismic Performance of Regular and Irregular RC Multi-Storied Building

In modern structural engineering, lateral resilience of multistoried RC building is significantly affected by structural geometry. Structural irregularities in plan or elevation often led to non uniform distribution of mass, stiffness & strength which results in significant damage during earthquakes. This study presents comparative analysis of seismic performance of regular building (Rectangular shape building) and irregular building with different types of plan geometry (H, Plus, T, U and L shape building). The models consist of G + 12 storey consisting of same floor area of 720m2 analysed in accordance with IS 1893 (Part 1): 2016, IS 456:2000, and IS 13920:2016 and IS 875 (Part 1&2). Method used is response spectrum for zone III, IV & V with soil type II using etabs software. A comprehensive study is conducted to examine storey drift, storey displacement & base shear. Results indicate that corner re-entrant plan irregularities cause higher lateral displacement and drift compared to regular configuration. This demonstrates that plan irregularity significantly affects seismic stiffness and overall stability of RC structures.