Abstract
The preliminary design of seismically isolated R/C highway overpasses is the tar-get of a software based on the current design provisions of Eurocode 8 (Part 2) as well as on engineering decisions included in the expert system. The features of this expert system, which is aimed to facilitate the design of a highway overpass by isolating its deck with the inclusion of elastomeric bearings, are presented and discussed. For such an upgrade scheme a number of successive checks is necessary in order to select an optimum geometry of the bearings. The developed software includes a series of checks provided by Eurocode 8 (Part 2), in order to ensure the satisfactory seismic performance of the selected upgrade scheme. In doing so, the software accesses a specially created database of the geometrical and mechanical character-istics of either cylindrical or prismatic elastometallic bearings which are commercially avail-able; this database can be easily enriched by relevant data from laboratory tests on isolation devices. The basic assumptions included in the software are (a) modeling the seismic re-sponse of the bridge overpass as a SDOF system, and (b) only the longitudinal direction re-sponse is considered; it is common practice for seismically isolated bridge systems to restrain the transverse movement of the deck by stoppers. Moreover, the results form a number of tests performed in the Laboratory of Strength of Materials and Structures of Aristotle Univer-sity, verified the quality of the production process of a local producer of elastomeric bearings subjecting production samples to the sequence of tests specified by International Standard ISO 22762-1 (2005). Strain amplitudes larger than 250% resulted in the debonding of the elastomer from the steel plating. Artificial aging resulted in a small increase of the axial (ver-tical) stiffness and a small decrease of the shear (horizontal) stiffness of the tested bearings. More specimens must be tested to validate further these findings.
Original language | English |
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Title of host publication | ECCOMAS Thematic Conference - COMPDYN 2011: 3rd International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering: An IACM Special Interest Conference, Programme |
Publication status | Published - 2011 |
Event | 3rd International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering, COMPDYN 2011 - Corfu, Greece Duration: 25 May 2011 → 28 May 2011 |
Conference
Conference | 3rd International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering, COMPDYN 2011 |
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Country/Territory | Greece |
City | Corfu |
Period | 25/05/11 → 28/05/11 |
Keywords
- Bridges
- Knowledge-based systems
- Preliminary de-sign
- Seismic isolation
- Software
- Testing of elastomeric bearings