DOUBLE-FLOOR VIBRATION DAMPING DEVICE

PURPOSE:To reduce vertical vibrations without deteriorating the serviceability of double floors by tuning the composite damping characteristic frequency of vertical dynamic vibration damping mechanisms to the predominant frequency of a building floor slab, the damping mechanisms being distributed among a group of double-floor supports and fitted around and suspended from the supports. CONSTITUTION:A vertical dynamic vibration damping mechanism 11 comprises an additional mass 11b... integrally mounted on the lower end of an elastic body 11a the upper end portion of which is secured to a double-floor support 4 erected on a building floor slab 3, the additional mass being allowed to freely vertically vibrate. A charactersitic frequenty to be damped is freely adjusted according to the state of installation of the additional mass 11b. The vertical dynamic vibration damping mechanisms 11 are distributed among a group of plural double-floor supports 4 and are vertically slidably fitted around and suspended from the supports 4. The predominant frequency of the building floor slab 3 in earthquakes, etc., is tuned to the composite damping characteristic frequency (epsilon) of the vertical dynamic vibration damping mechanisms 11. Therefore, the effect of reducing the vertical vibration of the building floor slab 3 is provided and vibration of double floors for construction thereon can be damped at the same time.