Application of rheological fluid dampers for vibration control of buildings

Vibration problem of the building retrofitted with controllable rheological fluid damper was formulated in the paper. Moreover, the problem of the optimal friction force evaluation was also considered. Horizontal displacements of the model under consideration were caused by foundation motion. In case of the system retrofitted with magnetorheological dampers (MR), the signals generated in displacements’ sensors are converted into the current in coil exciting magnetic field in slits where the MRF fluid flows. In case of electrorheological dampers (ER) the electric field is formed between electrodes powered by controllable current generator. The electric or magnetic field provokes fluid polarization in damper, what influences on the value of friction force. The intensity of vibrations was evaluated based on a functional depending on accelerations of certain points of the system. Results of computer simulations were also presented in the paper.APPLICATION OF RHEOLOGICAL FLUID DAMPERS FOR VIBRATION CONTROL OF BUILDINGS
The paper formulates a mathematical description of the vibrations of a building equipped with controllable rheological fluid dampers. The task of optimal selection of friction forces is also presented. A model is considered whose transverse vibrations are excited by the movement of the foundation. In a system with magnetorheological (MR) dampers, signals from displacement sensors are processed into currents flowing in coils that excite a magnetic field in the gaps through which the MRF fluid flows. In the case of electrorheological (ER) dampers, an electric field is generated between electrodes powered by a controllable voltage source. Under the influence of a magnetic or electric field, the fluid in the controllable damper undergoes polarization, which affects the value of the friction force. To assess the intensity of vibrations, a functional was adopted whose values depend on the acceleration of selected points of the structure. The considerations are illustrated by an example simulation of the vibrations of the analyzed building. (…)

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