Optimal design of seismic retrofitting of RC frames with eccentric steel bracing

This paper focuses on optimal design for dissipative steel bracing in seismic retrofitting of gravity load designed RC frame buildings. An optimized iterative force/strength-based design procedure is presented, for simultaneous yielding of bracing of all storeys, in order to induce an global damage mechanism in the building which maximizes the hysteretic damping effect. The procedure complies with the capacity design rule, whereby the bracing system enters the plastic range before the existing RC frame. The iterative design procedure of the system is applied here to a regular RC shear frame, with various design behavior factors.