Seismic Behaviour of Asymmetric RC Structures Using NBC 105:2020

Suraj Khadka

doi:10.55524/ijirem.2025.12.2.11

Abstract

Since, today it is not possible to design the structure with regular shape, my thought is that vertical and/or perpendicular irregularity shall possibly evolve. Failure of structures under dynamic loading is due to these irregularities, which are made responsible for the failure. Recent earthquakes and history indicate that plan asymmetric structures are very prone to being damaged by earthquakes-frequency, due to combination torsional and translational stuff. Consequently, seismic behavior of such structures in the seismic active regions is needed to minimize the intrinsic seismic damages. This thesis attempted to study the torsionality of reinforced concrete structures of plan asymmetry subjected to the effect of earthquake with torsional stuff parameters and at the same time provide a possible outcome for torsional influences. Regular reference and C- C shaped plan asymmetric 10 floor structures, three dimensional finite element models are prepared for the study and analysis is carried out using modal response spectrum system as per NBC 105(2020) in ETABS 2016. The results indicate that plan asymmetric structures are more prone than their normal ones. In order to analyze the model, a response spectrum system is used in ETABS software. The final seismic behaviour of the structures, such as, base shear, storey shear, member forces, overturning moments, displacements, stiffness and cross storey drifts are finally compared.

Keywords

Seismic Behaviour, RC Structures, Asymmetric RC Structures, NBC

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Cites this article as

S. Khadka "Seismic Behaviour of Asymmetric RC Structures Using NBC 105:2020", International Journal of Innovative Research in Engineering & Management (IJIREM), Vol-12, Issue-2, Page No-65-69, 2025. Available from: https://doi.org/10.55524/ijirem.2025.12.2.11