EQUIVALENT LINEARIZED MODEL OF DAMPER RESPONSE FOR SEISMIC DESIGN OF STEEL STRUCTURES WITH NONLINER VISCOUS DAMPERS

摘要

Damping devices are usually connected to other structural components to improve the seismic performance of steel structures. This paper presents a linearized model of the response of a nonlinear viscous damper in series with the associated bracing needed to connect the damper to the structure. The linearization of the damper-brace component is needed for preliminary seismic design of structures with nonlinear viscous dampers. The nonlinear viscous damper-brace component is represented as an equivalent linear elastic-viscous model by equating the energy dissipation per cycle of the damper to the energy dissipation per cycle of the equivalent linear elastic-viscous model. This linearization includes the effects of elastic flexibility of the structural components on the damper behaviour within a structure. To validate the equivalent linear elastic-viscous model, tests with predefined harmonic displacement histories are conducted on a practical 0.6-scale three-story structure with nonlinear viscous dampers. The test results are presented, and demonstrate that the equivalent linear elastic-viscous model for the damper-brace component is accurate for preliminary seismic design of a structure with nonlinear viscous dampers.