In-Plane Quasi Static Cyclic Testing of Reinforced Concrete Frames Retrofitted with Eccentric Steel Braces

Abstract

Steel bracing is an effective and economical retrofitting technique for upgrading deficient reinforced
concrete moment resisting frames typically found in the developing countries. Steel bracing not only increases the
strength, stiffness and energy dissipation capacity of the system but also provide sufficient ductility under an earthquake
event. This paper numerically investigates the seismic performance of eccentric steel braces connected diagonally to
reinforced concrete beam at a distance of Lbeam/6 from the face of the column. Static time history analysis was performed
on a single story reinforced concrete bare frame and eccentric steel brace retrofitted frame using a finite element
program. Results showed that frame retrofitted with eccentric steel brace changes the lateral load transfer path and
reduces the demands on the most crucial zone beam-column joint and as a result increases the strength, stiffness and
energy dissipation capacity of the frame as opposed to bare frame