Nonlinear Dynamic Response of HDRB and Hybrid HDRB-Friction Sliders Base Isolation Systems
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The isolation systems are usually made of rubber bearings that are sometimes coupled in hybrid combination with frictional devices; this is the case of an in-site experimental campaign, performed on a base isolated apartment building in Rapolla (south of Italy). Several dropout tests at initial displacements up to 17cm allowed to obtain in-site information on the true dynamic response of the isolation system (building and isolators). The tests carried out allow a comparison between the free vibration responses of a building, isolated by using a 28 HDRB isolation system only, or an HDRB-Friction Sliders Hybrid one. The paper highlights the main differences of the response in the superstructure (the structure over the isolation system) obtained by using only HDRB isolation system, or the Hybrid one (HDRB and Friction Sliders in parallel system). Analysis and comparisons of experimental data, show the influence of nonlinearities on structural higher modes amplification, especially observed by using the higher nonlinear Hybrid isolation system. Tests results confirm that, in the case of a regular superstructure, like the Rapolla building, the isolation system nonlinearities influence the structural response.
Keywordsbase isolation free vibrations friction sliders HDRB nonlinearity effects system identification
high damping rubber bearings
single degree of freedom
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- Aiken, I.D., Kelly, J.M., Tajirian, F.F. 1989Mechanics of Low Shape Factor Elastomeric Seismic Isolation BearingsEarthquake Engineering Research CenterThe University of California at BerkeleyReport UCB/EERC 89/13Google Scholar
- Asher, J.W., Hoskere, S.N., Ewing, R.D., Mayes, R.L., Button, M.R. and Van Volkinburg, D.R. (1997) Performance of Seismically Isolated Structures in the 1994 Northridge and 1995 Kobe earthquakes. In Proceedings, Structures Congress XV. Vol. 2., American Society of Civil Engineers, New York.Google Scholar
- Braga, F., Dolce, M., Ferrigno, A., Laterza, M., Marotta, G., Masi, A., Nigro, D. and Ponzo, F. (1997) Development of new materials for seismic isolation and passive energy dissipation – Part I: Experimental Tests on New Compound Elastomeric Bearings. In Proceedings of the International Post-SMiRT Conference Seminar on Seismic Isolation, Passive Energy Dissipation and Active Control of Seismic Vibrations of Structures, Taormina, Italy, August 25–27.Google Scholar
- Constantinou, M., Mokha, A., Reinhorn, A. 1990aTeflon bearings in base isolation I: TestingJournal of Structural Engineering (ASCE)116438454Google Scholar
- Constantinou, M., Mokha, A., Reinhorn, A. 1990aTeflon bearings in base isolation II: TestingJournal of Structural Engineering (ASCE)116455474Google Scholar
- Kelly, J.M. 1991Dynamic and Failure Characteristics of Bridgestone Isolation BearingsEarthquake Engineering Research CenterThe University of California at BerkeleyReport UCB/EERC 91/04Google Scholar
- Laterza, M. and Masi, A. (1996) Analysis of Experimental Investigation on Elastomeric Seismic Isolation Bearings. In Proceedings of the Eleventh World Conference on Earthquake Engineering, Acapulco.Google Scholar
- Satish, N., Sun, X. 2000Response of Base-Isolated USC Hospital Building in Northridge EarthquakeJournal of Structural Engineering12611771186Google Scholar
- Skinner, R.I., Robinson, W.H., Mc Verry, G.H. 1993An Introduction to Seismic IsolationJohn Wiley & sonsNew YorkGoogle Scholar