Review article
Engineering modelling of seismically isolated viaducts
Tatjana Isaković
; University of Ljubljana, Faculty of Civil and Geodetic Engineering, Ljubljana, SLOVENIA
Matej Fischinger
; University of Ljubljana, Faculty of Civil and Geodetic Engineering, Ljubljana, SLOVENIA
Abstract
The basic principle of seismic isolation is simple: to reduce seismic actions applied to the structure using special isolation devices. First, since the seismic isolation is a relatively new technology this basic principle is described in the paper. Then some recommendations for modelling the isolation devices are given. Isolated bridges are sensitive to several parameters, which usually do not affect the structures without isolation. Therefore more exact methods of analysis and models are usually necessary for the isolated structures. Especially important are precise models of pier foundations and the ground, the earthquake load in the long period range, a friction in sliding bearings, and column masses. The influence of most important parameters on seismic response of isolated viaducts is discussed and illustrated on the example of the first isolated viaduct in Slovenia - viaduct Ločica. The viaduct is situated at the site, where the problematic ground characteristics are combined with relatively strong seismicity. Nevertheless, due to the seismic isolation it was possible to choose common dimensions of structural elements, which were not greater then those, based on non-seismic loads.
Keywords
engineering modelling, viaduct, seismic isolation, isolation device, seismic response
Hrčak ID:
319852
URI
Publication date:
19.12.2002.
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