World’s Longest Sea Tunnel Seikan Tunnel You must have seen the tunnel built in the mountains or you will have heard about it, but you will be surprised to know that there are tunnels in the depths of the ocean.
It is not easy to cut down mountains and make tunnels under them, but digging tunnels under the foothills of the sea is a very difficult task. This requires hard work for many years, high tech and firm intentions. There is a similar sea tunnel in Japan named ‘Seikan Tunnel’. This is the longest tunnel in the world.
Japan is divided into four main islands and some small islands. This tunnel connects these islands, Honshu and Hokkaido by way of water under water. Seikan Tunnel spreads under Tsugara Straits which means it has been constructed 24 meters below the sea water surface. The total length of this tunnel is 53.85 kilometers.
Why did the Seikan tunnel be felt? Its information is also necessary. The flow of water is very fast in the Sanguu Strait. Passenger boats passing through this period of cyclical storms had to cancel their travels many times, and there was considerable loss of life and property due to accidents, so for the safe movement of the passengers it was decided to prepare tunnels under water.
A geographical survey of this place was conducted in 1946 and excavated for about twenty-one years. After excavation, its construction work continued for nearly fourteen years. One of the specialties of the construction of this tunnel was that its construction started simultaneously from both the islands of the two edges. Finally, on March 10, 1985, the two islands were reconnected by removing the final interruption in the middle of the tunnel.
Three tunnels were made for this huge tunnel.
In addition to the main tunnel, a pilot tunnel and an operational tunnel were also dug. Thus, about two hundred kilometer long tunnel was constructed altogether. It was a very complex task. Path-guided tunnel was used to check the ground and remove stools, water etc.
Various types of instruments, luggage and laborers were kept in operation tunnel. In this construction of this eleven-meter wide and nine-meter high tunnel, about one crore thirty thousand cubic meters of soil and rocks were pulled out and 1,800 thousand tons of steel was used with eight lakh seven thousand tons of cement.
This work required extremely high tech and micro survey and monitoring. It was filled up four times in it. After the sudden flooding of the water, obstacles in the construction work also came.
Most water was filled in May 1967 with a speed of seventy tons per minute and at that time due to the removal of water in the middle, the main work had been delayed for four months, but with these difficulties, the Japanese engineers were not terrified.
One of the specialties for the construction of this tunnel was that it was constructed from machines that cut the earth in a flat form. Creating pathways for accidental needs between the main tunnel and other two tunnels, they were also connected to each other.
The latest electronic gadgets, laser beams, computers, explosives, debris stacking machines and the movement of trains had given this tunnel the nature of a factory operating within the sea.
Ultimately, their combined efforts succeeded and they were successful in creating their own unique sea tunnel in the world. It is the world’s longest tunnel under sea. – Anand Kumar Anant