Hysteretic model for steel energy absorbers and evaluation of a seismic design strategy using minimal-damage performance objectives

This paper evaluates an alternative seismic design approach for steel structures that concentrates damage in easy-to-replace steel energy dissipation devices and protects the main structural members from yielding with capacity design rules. This approach is further enhanced by using rate- dependent dampers in parallel to steel devices to achieve drift reduction and protection of drift-sensitive non-structural elements. A model for steel energy dissipation devices is proposed and calibrated against experimental results. The model is found able to accurately predict the experimentally obtained hysteresis and is implemented in the Open Sees software for use in seismic response analysis. A prototype steel building equipped with steel devices and viscous dampers is designed according to explicitly defined minimal-damage performance objectives. Seismic analyses results indicate that the building is able to achieve immediate occupancy under the design seismic action and rapid return to occupancy under the maximum considered seismic action