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For the past several years, seismic isolation systems have been focused in the seismic design of industrial facilities. This paper deals with the response reduction effect by friction. Friction is expected to decrease the relative displacement by dissipating the vibration energy. The relative displacement between structure and support becomes larger at long period in the case of linear system. Therefore, the response reduction effect by friction should be utilized positively in the seismic design. However, the response magnification of acceleration is used in the seismic design. The acceleration becomes larger by stick and slip motion. Therefore, the response reduction effect by friction is evaluated from the viewpoint of energy. The ratio between elastic energy and input energy is utilized. In this paper, “Response Reduction Map” based on energy forlong period friction system is suggested. This map shows the range that energy response ratio is less than the ratio of the linear system. The response reduction map without complex non-linear time history calculation caneasily obtain the proper parameters, such as natural period or friction force. In this study, the response reduction map by the artificial earthquake wave calculated from the design spectrum is shown.Next, the advanced friction damper is developed by using above energy based result. The friction part of the advanced friction damper is constructed by using MR fluid. The characteristics of the friction part are evaluated.

This paper deals with response reduction effect by friction behavior. Friction is expected to absorb seismic energy. This effect should be utilized positively in seismic design. For past several years, seismic isolation structures have been focused in seismic design of industrial facilities. Seismic isolation effect is controlled by the friction characteristic exists in friction support. Therefore, adjustment of frictional force becomes a very important. In this paper, "Response Reduction Map" for long period friction system is suggested. This map shows the range that response magnification is less than 1 and less than the response of linear system. The response reduction map without complex non-linear time history response calculation can easily obtain the response magnification. At first in this study, the response reduction map by actual earthquake wave is shown. Next, the response reduction map by the artificial earthquake wave calculated using design spectrum is shown.