Experimental Investigation on Retrofitted RC Moment-Resisting Frames using NSD Yielding Dampers

Retrofitting in reinforced concrete structures has been one of the most important research topics in recent years. There are several methods for retrofitting RC moment-resisting frames, the most important of which is the use of steel reinforcement systems using yielding dampers. With the proper design of yielding dampers, the stiffness of moment-resisting frame systems can be increased to the required amount so that the ductility of the structure does not decrease significantly. In the present study, two experimental specimens of RC moment-resisting frames with a scale of one-third were loaded in the laboratory. In these experiments, the effect of retrofitting RC frames using non-uniform slit yielding dampers (NSD) was investigated. Based on the experimental results of the samples, the seismic parameters of stiffness, ductility, ultimate strength, strength reduction factor and energy dissipation capacity were compared. The results showed that the retrofitted frame had a very significant growth in terms of stiffness, ultimate strength and energy dissipation capacity. Although the strength reduction factor and ductility in the retrofitted structure decreased, in general, the behavior of the frame with NSD yielding dampers was evaluated better than the bare frame.