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Influence of planar irregularities on seismic responses of RC building


Understanding and predicting the behavior of buildings is a prime engineering interest for better seismic design of building system and this becomes even more important for buildings with planar irregularities. In this study, a detailed numerical investigation was carried out to enhance the understanding of seismic responses of buildings with planar irregularity. Four common and widely visible irregular shapes viz. C, L, I, and T shapes were considered. Two ground excitations with different ranges of dominant frequency were utilized to excite the irregular buildings. Both the modal and time history analyses were carried out and important dynamic features such as modal characteristics, base shear, roof displacement, roof acceleration, and drift of the irregular buildings were predicted. Different irregularity parameters in terms of planar geometry of the buildings were defined to find the most appropriate parameter to represent the seismic responses of the irregular buildings. It was found that among the various irregularity parameters defined, the overall aspect ratio i.e., L/B ratio of buildings are highly correlated with the seismic responses of the buildings. However, the seismic responses of the irregular buildings varied a lot from each other depending on the nature of the earthquake and planar irregularity. It was also found that I and T shapes buildings had the highest seismic responses among the considered buildings.

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MNH: Research theme, simulation, analysis, and writing manuscript. MBZ: Suggestion and comments to improve the quality. MGK: Simulation and data analysis. AKD: Simulation and data analysis.

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Correspondence to Md. Naimul Haque.

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Haque, M.N., Zisan, M.B., Kibria, M.G. et al. Influence of planar irregularities on seismic responses of RC building. Asian J Civ Eng 22, 995–1009 (2021).

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  • Planar irregularity
  • Seismic response
  • Time history analysis
  • Base shear
  • Story displacement
  • Story acceleration