明石海峽大橋介紹

1、Akashi-Keiko bridgeBy Wu Hao&Zhao ZujunCONTENTSBackgroundLocationIntroduction1234MiracleBackgroundAt 6:40 a.m. on 11th ,May, 1955, over 100 students took on a ferry, preparing to cross, Akashi Strait.At 6:56 a.m. ,the ferry crashed into another big one because of the heavy fog when it was about to l

2、eave the port.The ship sank in just 5 minutes , resulting in the death of 168 adults and children. All the people around Japan were astonished by this tragic accident. Therefore, it was urged that a bridge be built across Akashi Strait by the people whose relatives died in this accident.LocationThe

3、bridge is located between Honshu and Shikoku, crossing the Akashi Strait.The main span is 1991m,and the whole length of the bridge is 3911m. The girder is 35.5m in width and 14m in depth.It can resist a magnetitude-8.5 earthquake and wind speed of 80m/s.Introduction The towers are 283m in height, ea

4、ch of which consists of two cross-shaped hollow steel columns, connected by five pairs of cross sticks and two traverse beams. The distance between the centers of columns is between 46.5m35.5m. The profile size of sections of the tower ranges from 6.6m by 14.8m to 6.6m by 10.0m from the bottom to th

5、e top.TowersIntroductionThe strength of the cable is 1800MPaOne cable consists of 290 PWS strands, each of which consists of 127 steel wires, which is 5.23mm in diameterThe total weight of steel wires used in the bridge is 57700 tons.IntroductionThe long hangers are made of parallel steel wires (PWS

6、) ,while the short ones are manufactured with carbon fiber reinforced cables (CFRD). Introduction The main span was designed to be 1780m at first. Afterwards, it was changed into 1990m. At the same time, the two-way railways were cancelled because of the lack of construction experience of steel-box

7、girders in Japan. Therefore, the steel truss girder was applied to the design.IntroductionThe anti-seismic ability Akashi-Keiko bridge creates the new record of 20th century on the construction history of bridges. It can resist to a magnetitude-8.5 earthquake. On 17th ,January, 1995, a magnetitude-7

8、.3 earthquake occurred in Kobe (4km away from the bridge). 5000 people died from the disaster and 100 thousands houses collapsed into ruins. However, the bridge survived the earthquake, and a slight displacement of the abutment and anchorage on the southern coast occurred during the earthquake. As a

9、 result, the length of the bridge increased by 0.8m. IntroductionThe wind resistance ability Apart from the earthquake, it must be ensured that the bridge can resist to the wind speed of more than 200 km. Therefore, a wind tunnel test was performed on a 1:100 model. 20 tuned mass dampers (TMD) were

10、installed on the tower.0147The first one which broke the world record and exceeded one mile (1609m).The longest side span in the world, 960m in length.The size of the section is 35.5m by 14.0m, the depth of which is larger than any other one of suspension bridges in the world.The highest steel tower in the world, 297m in height.Main spanSide spanSteel towerSteel truss girderMiracleAkashi-Keiko bridge is a miracle in the engineering history of the world.