Seismic Performance of High-Rise RC Buildings with Square and Circular Columns Using Fluid Viscous Dampers: Time History vs. Pushover Analysis

Abstract

This study presents a comparative evaluation of the seismic performance of high-rise reinforced concrete (RC) buildings with square and circular columns, analysed with and without fluid viscous dampers (FVDs) using nonlinear time history and pushover methods in ETABS 2022. Four structural configurations were investigated: square columns without FVDs (SC), square columns with FVDs (SCFVD), circular columns without FVDs (CC), and circular columns with FVDs (CCFVD), under identical geometric and material properties. Seismic loading was defined in accordance with EN 1998-1, and Imperial Valley-02 ground motion was used for dynamic simulation. Results indicate that, without dampers, circular columns reduced dynamic base shear demand by up to 20% compared to square columns, although exhibiting slightly longer fundamental periods (≈3%). The incorporation of FVDs significantly enhanced seismic performance in both column types; however, circular columns demonstrated superior efficiency. Fundamental time periods were reduced by 24% in SCFVD and 43% in CCFVD, with CCFVD exhibiting a 27% shorter period than SCFVD. Under time history analysis, base shear decreased by 31% in SCFVD and by 44% (X) / 42% (Y) in CCFVD relative to the square-column baseline. However, Pushover analysis showed even greater reductions, reaching 35% in SCFVD and up to 74% in CCFVD. It was clear that Circular column system combined with FVDs provided the most efficient seismic response, achieving the lowest time periods and base shear demands. Thus, the study demonstrate that circular columns enhance the effectiveness of FVDs and offer superior seismic performance compared to square columns in high-rise RC buildings, particularly when evaluated using nonlinear dynamic analysis.