Energy Based Design of Friction Damped Vertically Irregular Buildings

ABSTRACT To reduce the adverse seismic effects on structures, friction dampers are commonly used as a supplemental energy‐dissipating system. Various codes have specified some guidelines for the use of such devices, but a simple and accurate design methodology is still needed for retrofitting buildings, particularly vertically irregular buildings, with these devices. In this work, a novel and simple methodology for designing friction damper in vertically irregular reinforced concrete frame buildings using an energy‐based principle is explored. For the investigation, three different irregular reinforced concrete buildings with and without damping systems, such as 5‐ and 10‐story building frames with setbacks at different locations, are examined. To validate the design method, nonlinear static pushover and nonlinear time history analysis of model buildings are used to evaluate the parameters, that is, formation of hinges, inter‐story drift ratio, and storey displacement, which are closely related to building damage. Findings show that the addition of friction dampers in vertically irregular building frames significantly improves the seismic behavior of such buildings.