95-0020 Retofit of Non-Ductile Reinforced Concrete Frames Using Friction Dampers R.S.Rao, P.Gergely, R.N.White 1995 Cornell University 190 PB97-133508 15 A comprehensive study of evaluation of damping systems using shaking table studies and subsequent modeling has been completed and initial design recommendations were proposed at NCEER. This report extends the knowledge base concerning friction damping devices, suggests design solutions that are feasible from both engineering and economic perspectives, and evaluates the performance of these designs. Moreover, design procedures based on capacity-demand spectra developed in numerous NCEER projects were extended to procedure specific design guidelines for friction dampers. The experience gained from this project will further enhance newer developments in seismic codes for retrofit of lightly reinforced concrete frames. Friction dampers. Slotted bolted bracing systems. Friction damped bracing systems. Nonductile concrete frames. Gravity load designs. Retrofitting. Reinforced concrete frames. Masonry infill walls. Shaking table tests. Time history analysis. Simplified design methods. Inelastic demand spectrum method.