Comparative Study of Seismic Analysis of Vertically Irregular R.C. Frame Using Indian and Euro Code

Abstract:The present study conducts a comparative evaluation of the seismic performance of reinforced concrete (RC) building frames designed in accordance with two globally accepted design codes: the Indian Standard (IS 1893:2016) and the European Standard (Eurocode 8). Structures with vertical irregularities are known to be more susceptible to seismic damage, particularly when appropriate strength and detailing measures are not implemented. High-rise buildings, especially those exhibiting geometric discontinuities, require a comprehensive assessment of their seismic response to ensure safety and resilience. This research investigates a G+22 storey RC building characterized by vertical geometric irregularities. The seismic analysis is carried out using ETABS software, employing the Response Spectrum Method (RSM) to evaluate structural response parameters, including storey drift, overturning moment, storey shear, and lateral displacement in both principal directions. The study highlights the practical differences between the two codes by comparing their design implications. In particular, it is observed that structures analyzed under IS 1893 tend to exhibit relatively lower response values that remain within acceptable limits, whereas Eurocode 8 analysis results in higher seismic demand due to its detailed spectral definitions and consideration of site-specific soil characteristics. This comparison underlines that IS 1893 offers a more conservative design approach, particularly beneficial for seismically active regions. The research further emphasizes the relevance of adopting international standards, such as Eurocode 8, for improving construction practices and enhancing structural safety in regions influenced by global construction norms, including the Gulf countries.