Study On The Design Parameters' Choice And Structural Scheme For The Super-Long Trestle Bridge Of Hangzhou Bay Bridge

Hangzhou Bay is a famous bay in the middle-east of China, which is well-known for its horn-shaped estuary and the surging Qiantang tide that happens once a year in its upstream.The Hangzhou Bay Bridge is 36 kilometers long, which will break the longest bay-crossing bridge record in the world. For the construction of this great bridge, a 9.8 kilometers long trestle is being built in the southern shore of the bay, which will also update the longest trestle record.The difficulties for the construction do not only come from the large scale of the trestle, but also from the complicated and diverse ocean environment. The wind, wave, flow and scour offer great challenges to the design and construction.The difficult points for the design not only rest with no suitable codes about such kind of structure, but also with the determination of the parameters of wind load, wave load, flow load and scour, which have much to do with the economy and safety of the trestle.A three-level design criterion was set up in this paper, which requires structure to remain elastic during work state, to be repairable after non-work state, and not to collapse even in disaster state. The traits of the flow, wave and local scour are studied, whereupon the parameters and the computing methods are presented. The trestle is divided into two sections, i.e., a general section and a deepwater section, and the tubular steel piles foundations are designed out accordingly. Through the practice of design and construction, it has been proved that the determination of the design parameters and structural scheme are successful, and it is a good example for similar trestle structures.