Proceedings Vol. 9 (2003)
ENGINEERING MECHANICS 2003
May 11 – 15, 2003, Svratka, Czech Republic
Copyright © 2003 Institute of Theoretical and Applied Mechanics, Academy of Sciences of the Czech Republic, v.v.i., Prague
ISSN 1805-8248 (printed)
ISSN 1805-8256 (electronic)
list of papers scientific commitee
pages 214 - +9p., full text
Wind 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.
back to list of papers
Text and facts may be copied and used freely, but credit should be given to these Proceedings.
All papers were reviewed by members of the scientific committee.