EXPERIMENTAL TESTING AND ANALYTICAL MODELING OF SEMIACTIVE FLUID DAMPERS FOR SEISMIC PROTECTION

The development, experimental testing, and analytical modeling of an i ntelligent seismic response control system is described in this paper. The control system is in the form of semiactive fluid damping devices which may be installed within the lateral bracing system of buildings or as part of a seismic isolation system for bridges or buildings. Th e dampers have mechanical properties which can be modified through a c losed-loop feedback control system which utilizes the measured earthqu ake excitation and/or the response of the structural system. Further, the dampers exhibit fail-safe characteristics in that, in the event of failure to operate as semi-active devices, the dampers convert to pas sive high-damping devices. The dampers were extensively tested to dete rmine the mechanical properties and the dynamic behavior of the device s. Furthermore, mathematical models for describing the damper behavior were developed and utilized for analytically predicting experimental results.