Transport and Infrastructure Minister Cahit Turhan, Turkey's mega projects that built withstand major earthquakes, said: "As July 15 Martyrs and Fatih Sultan Mehmet Bridge with Eurasia and the Marmaray tunnel 'mega-projects' earthquake as well as strong winds against the resistance." He said .
Minister Turhan made an assessment regarding the earthquake resistance status of major projects such as roads, bridges and tunnels, which have come to the agenda following the earthquakes in Manisa, Ankara and Elazig recently.
Transport and Infrastructure Ministry coordinated the implementation of a "mega projects" when designing any kind of possibility of thought that expresses Turhan, "Turkey's built due to the earthquake zone roads, bridges and tunnels are made keeping in earthquake factor at the forefront." He said.
Pointing out that Osmangazi and Yavuz Sultan Selim Bridges are designed to survive even in the "very big" severe earthquake that may occur about 2 thousand 500 years, Turhan emphasized that the fault lines in North Marmara and Black Sea were examined for the two bridges.
Turhan said, “The studies of determining the probability of seismic (earthquake) damage analysis of bridges, nonlinear ground response analyzes, fault displacement probability analysis were done. In addition, special support design studies were carried out to reduce seismic effects. ”
“Two bridges are strengthened”
Underlining that the July 15 Martyrs and Fatih Sultan Mehmet Bridges were also seismically strengthened, Turhan said:
“The reinforcement works were carried out in order to prevent possible damage in the event that both bridges are resistant to major earthquakes, the extension of the bearing seat base, the anti-fall cable assembly, the replacement of the existing supports, the existing expansion joints, the tower tower collision and the possible damage. Within the scope of the major repair and structural reinforcement of Fatih Sultan Mehmet Bridge, changing the suspension ropes, strengthening the towers, strengthening the box beam end diaphragms, changing the main cable fears, pendulum supports and main cable clamps, hanging plates, renewing and inspecting the main cable winding system. All necessary work was carried out. ”
Thus, Turhan pointed out that both bridges are achieved with seismic and structural reinforcement studies according to the current specifications, and that Osmangazi and Yavuz Sultan Selim bridges are provided with equivalent seismic durability. " said.
“Eurasia and Marmaray are among the safest places in the earthquake”
Turhan pointed out that projects such as the Eurasia and Marmaray Tunnels passing under the Sea of Marmara are also made to be one of the safest places in the possible earthquake that may occur in Istanbul, monitoring systems (26 accelerometers, 13 inclonometers and 6 3 dimensional displacement sensor) as well as the Train Central Control System associated with the Kandilli Early Warning System was built.
Considering earthquake loads, tsunami effects and liquefaction, Turhan said that the Eurasia Tunnel, designed according to the latest international standards, was constructed with 7,5 seismic seals that could be on a North Anatolian fault, with a seismic resistance:
“With the established Health Health Monitoring System, 9 accelerometers along the tunnel, 3 displacement sensors that monitor in 3 dimensions in 18 locations at seismic connection points were positioned and put into operation. The system, which was built under the Bosphorus, will be able to continue without any damage even in the severe earthquake that may occur every 500 years in Istanbul, and it can be put into service with minor maintenance in a very severe earthquake that is likely to happen every 2 years. ”
Tsunami waves are also considered
Turhan emphasized that the Marmaray Tunnel was designed to be extremely rigid in terms of earthquake resistance due to its being the deepest underwater tunnel ever built in the world and its proximity to an active geological fault line.
Indicating that the tunnel was built with the aim of getting out of a 7,5 magnitude earthquake with zero safety risk, minimum loss of function, watertightness in sunken tunnels and joints, Cahit Turhan said:
“Flexible earthquake joints were made at each junction point between the segments in the tube tunnel in order to minimize load transfer and seismically isolate the two structures. An early warning system was established in Marmaray to prevent the trains outside the tunnel, the tunnel outside the tunnel from entering here during the earthquake and after the earthquake, and to ensure that the insiders are pulled to a safe place. The entrance structures of the stations were increased by 1,5 meters against the tsunami waves. ”
Stating that security and robustness are always prioritized in all projects carried out under the coordination of the Ministry, Minister Turhan said, “All the 'mega projects' such as the July 15 Martyrs and Fatih Sultan Mehmet bridges, Eurasia and Marmaray tunnels are resistant to heavy winds as well as earthquakes.” he said.