Study on viscous-friction series damper for industrial facilities (Mechanism and basic performance of damper)

Abstract

This study proposes a viscous-friction series damper. The series damper consists of an oil damper and a friction damper connected in series. Long period and long time seismic waves were recognized as new problems by the Great East Japan Earthquake. In the case of those seismic waves, there are risks that performance of damper decreases. For example, temperature of inner fluid of viscous dampers may increase, and fatigue failure may occur in steel dampers by such earthquakes. On the other hand, friction dampers have high durability, but they don't operate with small input. Proposed series damper compensates for these weak points. In the case of small input, only the viscous damper operates. In the case of large input, both dampers operate, so energy absorption is divided and the durability is increased. In this paper, an analysis model of the series damper is introduced, and numerical analysis is carried out in order to investigate behavior of the series damper. The target of vibration control is a boiler structure. As a result of analysis, response of the structure with the series damper was smaller than response without the damper. In addition, response of the structure with the series damper approached response with an ordinary viscous damper by increasing friction coefficient. Then test model of the series damper is fabricated, and load experiments by sinusoidal waves are conducted. As a result of the experiments, stabile performance of the series damper against various input condition was confirmed. In addition, experimental results agreed well with analysis results, so proposed analysis model is efficient.

Keywords

• vibration control device
• damping
• seismic motion
• viscous damper
• friction damper