American Council of Engineering Companies, Grand Award - Engineering Excellence, 2002
American Council of Engineering Companies - NY, Diamond Award, 2002
Rapid Seismic Retrofit During Construction
The magnitude 7.6 earthquake that struck northern Turkey on August 17, 1999 caused widespread damage, even to buildings far from its epicenter. Among the structures affected was the passenger terminal at Ataturk International Airport in Istanbul, then under construction.
The local build-operate-transfer consortium, TAV Airports Holding, and its construction consultant, Turner International, retained Thornton Tomasetti and Tuncel Engineering of Istanbul to analyze the damage, evaluate the seismic resistance of the structure and develop a scheme to improve its seismic performance.
- In four months, the team devised and implemented an ingenious plan, including solutions never before used, for a seismic upgrade that would enable the terminal to remain functional in the event of another major quake, and for completion of construction on schedule.
- The retrofit scheme involved isolating the steel-frame roof by installing friction pendulum bearings as seismic isolators at the tops of the columns supporting it. These allow the roof to swing independently during an earthquake, reducing the demand on the columns below. The concrete columns were steel-jacketed and filled with grout for increased resistance and ductility.
- In strengthening seismic resistance beyond local design requirements, the upgrade should enable the building to withstand a design magnitude quake 50 percent stronger than that of the 1999 event.
- The rapid retrofit allowed the terminal to open on time, in January 2000.