Assessment of Earthquake Performance of Irregular Building Structures

Abstract

Rapid urbanization has led to the construction of an increasing number of high-rise buildings, making seismic safety a critical aspect of structural design. The objective of this study is to evaluate the influence of building geometry on the seismic performance of reinforced concrete (RC) buildings by comparing symmetrical and asymmetrical plan configurations. A 10-storey RC building with L-shaped, T-shaped, and Y-shaped layouts was modelled and analyzed using ETABS in accordance with IS 1893 (Part 1): 2002. The Equivalent Static Method was adopted to determine the seismic response, and key parameters, including lateral displacement, base shear, storey drift, storey shear, and seismic coefficients, were evaluated. The results indicate that building shape has a significant effect on seismic behaviour, with asymmetrical configurations exhibiting greater lateral displacement and storey drift than more regular layouts due to increased torsional effects. The study demonstrates that ETABS provides an efficient platform for seismic analysis and highlights the importance of considering plan geometry during the design stage to improve the earthquake resistance and overall structural performance of reinforced concrete buildings.