000001556 001__ 1556
000001556 005__ 20141118153503.0
000001556 04107 $$acze
000001556 046__ $$k2003-05-12
000001556 100__ $$aNáprstek, J.
000001556 24500 $$aDynamics of a spherical vibration absorber

000001556 24630 $$n9.$$pEngineering Mechanics 2003
000001556 260__ $$bInstitute of Theoretical and Applied Mechanics AS CR, Prague
000001556 506__ $$arestricted
000001556 520__ $$2eng$$aWind excited vibrations of slender structures such as towers, masts or certain types of bridges can be reduced using passive or active vibration absorbers. If there is available only a limited vertical space to install such a device, a spherical type of absorber can be recommended. In general, it is a semi-spherical horizontal dish in which a sphere of a smaller diameter is rolling. Ratio of both diameters, mass of the rolling sphere, quality of contact surfaces and other parameters should correspond with characteristics of the structure. The spherical absorber is modelled as a holonomous system. Using Lagrange equations of the second type, governing non-linear differential system is derived. The function and effectiveness of the absorber identical with those installed at the existing TV towers was examined in the laboratory of the Institute of Theoretical and Applied Mechanics. The response spectrum demonstrates a strongly non-linear character of the absorber.  The response amplitudes at the top of a TV tower with spherical absorber were reduced to ¤ of their original values.

000001556 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000001556 653__ $$a

000001556 7112_ $$aEngineering Mechanics 2003$$cSvratka (CZ)$$d2003-05-12 / 2003-05-15$$gEM2003
000001556 720__ $$aNáprstek, J.$$iPirner, M.
000001556 8560_ $$ffischerc@itam.cas.cz
000001556 8564_ $$s316849$$uhttp://invenio.itam.cas.cz/record/1556/files/296-Jiri-Naprstek-PT.pdf$$y
             Original version of the author's contribution as presented on CD, DYN.
            
000001556 962__ $$r971
000001556 980__ $$aPAPER