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Immersed Tube Tunnel

Immersed tube, also called Sunken Tube, technique of underwater tunneling used principally for underwater crossings. The method was pioneered by the American engineer W.J. Wilgus in the Detroit River in … Continue reading

New Austrian Tunneling Method (NATM)

The New Austrian Tunneling method (NATM) was developed between 1957 and 1965 in Austria. It was given its name in Salzburg in 1962 to distinguish it from old Austrian tunnelling … Continue reading