fib Symposium 2020 in Shanghai | Akio Kasuga | A Challenge to Non-Metallic Bridges скачать в хорошем качестве

fib Symposium 2020 in Shanghai | Akio Kasuga | A Challenge to Non-Metallic Bridges

The first non-metallic bridge was built in 1990 in Tochigi, Japan. AFRP shear reinforcement and prestressing tendons were used instead of steel. However, the cost of this proto­type non-metallic bridge was 2.5 times compared with usual prestressed concrete bridges. And our R&D of non-metallic bridges was suspended. In 2010, West Nippon Expressway Company announced the joint research project regarding non-metallic bridges. Then their most important require­ment was 1.5 times the initial cost of the structure. Usually, the life cycle cost of bridges is 2 to 3 times compared with the initial cost. Therefore, 1.5 times the initial cost and no maintenance cost are acceptable for the bridge owner. At that time, Sum­itomo Mitsui Construction has experiences of non-metallic bridges and our joint research was started in 2010. In order to suppress the cost of new structures, fiber rein­forced concrete, butterfly web and AFRP internal and exter­nal tendons were used. In 2015, the temporary bridge was built in Nagasaki to collect data of the bridge. And in 2019, the highway bridge in Tokushima will be constructed. In order to realize the non-metallic bridge, many leading-edge technologies since 1990 are gathered. Non-metallic bridges can regain their extreme high durability because they eliminate the factor of deterioration, steel and reinforcements.