Seismic Response Control of Reinforced Concrete Smart Structures Using Base Isolation and Fluid Viscous Dampers

Abstract

This study quantifies the seismic response of a ten-story reinforced concrete smart structure with base isolation and supplemental fluid viscous dampers. A 3D SAP2000 model was created for a reinforced concrete moment-frame building with a central shear wall, 10 stories, a total height of 36.0 m, and plan dimensions of 30 m by 42 m. The comparison of three structural configurations was carried out under El Centro earthquake excitation in the principal horizontal directions: a conventional fixed-base model, a base-isolated model, and a base-isolated model with supplemental fluid viscous dampers in the lower stories. Structural response records were evaluated, including fundamental period, base shear, roof displacement, and peak ratio of interstory drift. The designed earthquake-resistant systems resulted in significant seismic force and drift demand reductions. In the numerical comparison, the base-isolated and base-isolated with fluid viscous damper models had fundamental periods of 2.366 s and 2.345 s, respectively, compared to the fixed-base model, which had a fundamental period of 0.846 s. The increase in the fundamental period shifted the structural response away from the high-energy region of the earthquake response spectrum, thereby reducing seismic force transfer to the superstructure. The introduction of base isolation resulted in a reduction of peak base shear in the X direction from 73,848 kN to 7,881 kN and in the Y direction from 47,414 kN to 15,622 kN. The combined base isolation and damper system decreased the interstory drift by 76% from 0.509% to 0.121% in the X direction and 63% reduction in Y direction from 0.319% to 0.119%. Significant reductions in lower-story drift concentration were also observed after the addition of fluid viscous dampers. Also, the combined system decreased the drift of Story 1 and Story 2 by 68.33% and 68.54% in the X direction and by 58.76% and 59.91% in the Y direction. The findings show that base isolation mainly reduces the transfer of seismic forces, whereas fluid viscous dampers offer extra lower-story drift controls and enhance overall seismic performance. The results further demonstrate that the combined seismic protection strategy significantly improved the seismic resilience and dynamic performance of the reinforced concrete smart structure under earthquake excitation.