Turkey has introduced a new isolated bearing system which is designed to preserve the alignment of critical structures while saving millions in construction costs. It may soon be put to use on a high-speed-rail project in Turkey and has been proposed for California’s high-speed-rail-system as well. In the second phase of the 533km long high-speed-rail line between Ankara and Istanbul, a segmental displaced control isolation system manufactured by Vallejo, California will be included. This will be done by a CCCI Consortium which is a design-build partnership of the China Railway Construction Corp., the China National Machinery Import & Export Corp., Istanbul based Cengiz Insaat and Ankara based IC Ictas Insaat. The first phase was completed in March 2009.
The isolated bridge system not only improves the chances of preserving operations after an earthquake but also reduces shear loads in foundations by 20%. It is therefore, less expensive to build.
The system was tested on a 30ft long bridge model in May at the Pacific Earthquake Engineering Research (PEER) Simulator Laboratory at UC Berkeley’s Richmond Field Station. Historic trembles were created which even went up to the level of 1995 earthquake of Kobe (Japan) that was measured 6.9 on the Richter scale. It was found that after the trembles stopped, the model remained operational.
EPS performed seismic retrofit work on the Ataturk Airport International Terminal after the 1999 earthquake. Since then, Turkey has used EPS bearings in 10 important structures. All the four major viaducts of the Trans-European Highway use EPS friction pendulum bearings.