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The first Imperial Invention Prizes for both building construction and civil engineering technologies

The “Taisei Truss” developed by our company won the first Imperial Invention Prize in the area of building construction and civil engineering in 1967. This was granted for the most superior invention of the year. The Taisei Truss is a unique space truss with superior dynamic characteristics, such as lightness and high rigidity. It enables prefabrication using identical units. As a pioneering space truss that can compose free curved surfaces, the Taisei Truss was broadly used for large facilities without columns, such as in power plants, other types of plants, and domes. Moreover, the rotating shield method, which we jointly developed with Ishikawajima-Harima Heavy Industries Co., Ltd. (currently known as IHI Corporation), won the Imperial Invention Prize for the first time in civil engineering technology in 1997. With the rotating shield method, a single shield machine continuously excavates shafts and tunnels. The rotating shield method varies from the Horn method, which allows continuous excavation in both the vertical and horizontal directions or in the horizontal direction alone; the Kurun method, which allows bit replacement from the inside shield machine by sphere rotation; and the Derun method, which allows excavation of a shaft from a tunnel to the ground. We are the only corporation that has won the Imperial Invention Prizes for both technologies of building construction and civil engineering.