Performance Assessment of Different Retrofitting Techniques for Steel-Framed Buildings

The requirement for cost-effective critical infrastructure has made employing nonlinear analysis techniques an appealing choice. Estimating seismic loads on structures necessitates explicit consideration of inelastic structural behavior. Hence, nonlinear approaches such as pushover analyses have become more popular. In this study, the performance of a ten-story steel moment-resisting frame retrofitted with various bracings like diagonal-bracing, chevron bracing, x-bracing and k-bracing is evaluated using linear and nonlinear analysis. The responses, such as base shear, lateral load distribution, displacement, drift, and lateral stiffness, are determined using the ETABS-18 building analysis and design program. The results of the study show that the steel-braced frame systems have substantially greater strength and ductility capabilities than their unbraced or alternate steel-braced moment-resistant steel frame. Further, the unbraced steel frame has a low R-factor as compared to the bracing system due to the increased stiffness at the story level.