Authors: Rahul Solanki, Murlidhar Chourasia, Rahul Kumar Satbhaiya
Abstract: The seismic performance of reinforced concrete (RC) structures is significantly influenced by the geometry and detailing of their columns, which act as the primary load-bearing and energy-dissipating elements during ground motion. Among the available column cross-sections, rectangular shapes have traditionally been used due to ease of construction and integration with architectural plans. However, in high-seismic zones, circular columns are gaining attention for their superior ductility, confinement efficiency, and uniform stress distribution.This study presents a comparative analysis of the seismic behavior of RC frames with rectangular and circular columns, focusing on their performance under lateral loading conditions. An extensive literature review was conducted, highlighting the influence of column shape on key seismic performance parameters such as base shear capacity, lateral drift, energy dissipation, plastic hinge formation, and failure mechanisms. Analytical studies, experimental investigations, and code-based assessments consistently indicate that circular columns outperform rectangular ones in terms of ductility and post-yield behavior. Their symmetrical geometry allows better confinement of core concrete, resulting in enhanced resilience during strong ground shaking.Additionally, the review underscores the limitations of conventional force-based design methods in accurately predicting the inelastic behavior of structures, especially those with irregular geometries. Nonlinear static (pushover) analysis, displacement-based approaches, and accurate modeling of infill-wall interaction emerge as essential tools for realistic seismic performance evaluation.The findings of this study support the strategic replacement or incorporation of circular columns in RC frames to improve seismic resistance, particularly in retrofitting and performance-based design scenarios. While practical challenges such as increased formwork complexity exist, the benefits in structural safety and energy absorption justify their use. This paper serves as a reference for engineers and researchers aiming to optimize RC structures for improved seismic resilience through column geometry selection.
DOI: https://doi.org/10.5281/zenodo.16728432
