The suspension bridge longest in the world is the Çanakkale 1915 – in Turkish Çanakkale Boğazı Köprüsü – on the Strait of the Dardanelli in Türkiye. This imposing structure, inaugurated on March 18, 2022, has a total length of about 4608 meters and his central span from 2023 meters It allowed him to overcome the previous record for the longest span in the world established by the bridge Akashi Kaikyo in Japan. With a travel time of 6 minutessaves about an hour and a half of navigation with ferry.
The area where the bridge is located that connects the Turkish cities of Gallipoli And Lapsekipresents significant engineering challenges such as his high seismic activity and the passage huge tank ships, among the largest in the world. But the most fearsome enemy of this type of bridges are the strong windsin particular those who blow in the strait. Hence, its particular double cassone shape with two huge cassons connected by transverse beams aimed at guaranteeing the perfect aerodynamic stability. Wide 45 meters, a height of 70 meters On the sea level, it is a huge work: for its construction they have been used 180,000 tons of steel and have been invested 2.5 billion euro.
The Dardanelli bridge in Türkiye: the construction of the çanakkale 1915
The record bridge, also known as Ponte della Battaglia di Gallipoli of 1915was built in just under 5 years and designed by the engineering studio Cowi. To do this, it was necessary to resort to the use of elements prefabricatedprepared on the ground and assembled on site allowing a faster, confident and precise construction. For example, the steel sheets used to build the towers, were coupled first on the ground, in order to create modular portions from the weight of 160 tonsthen positioned at altitude and connected to each other. By doing this it was possible to reduce approximately 8 times the lifting initially expected.
Built the two towers were installed the two catwalks from 4330 mon both sides of the bridge, which allowed the positioning of the main cables. The cables, from the total length of their threads of 162,000 km, are made up of 144 wireson the main span (overall diameter of 86.9 cm) and 148 wires, on the side spans (overall diameter of 881 m). It should be emphasized, however, that the total length of the threads would be sufficient for surround the globe four times!
To conclude the work, particular lifting portals, from the capacity 450 tonshave made it possible to connect the individual councils of Ponte to the suspended cables and the FIP MEC SRL. of Selvazzano inside (PD) provided the anti -seismic devices and the special support devices of the bridge.
The special foundations of the bridge over the Strait of the Dardanelli
The bridge is located in an area with strong seismicity, about 20 km from the north-anatolic fault, the boundary between the Anatolian and the Eurasian plaque. The towers are positioned on Special foundations consisting of a so -called Zattera of Foundationan imposing and very heavy block of concrete and steel filled with water and resting on the ground reinforced by 196 steel pipes with a diameter of 2.5 meters each.
In these special foundations between the raft and steel poles a big one has been inserted gravel bed so that the two towers, when subject to a very high horizontal load, such as the seismic one, can move freely and dissipate energy without damaging the structure!
The Symbols bridge in Türkiye
Some dimensions have been defined even before the start of the design. The two main towers, in steel, are approximately high 318 metersa number that wanted to celebrate the Victory of çanakkale of March 18, 1918 (Graphically expressed as 03/18), which was a turning point in Turkish and world history.
Furthermore, also the central span, of 2023 meters and suspended between the two main towers, he wants to remember the 100th anniversary of the Turkish Republic, celebrated precisely in 2023. Furthermore, coloring is a clear reference to the national Turkish symbols, the red and white colors used, recall the national flag.
