On the Structural Characteristic of Long-Span Composite Cable-Stayed Bridges Using Steel Pipes as Main Girders
Shunichi NAKAMURA, Masayuki OKIMOTO, Tomonori TOMINAGA, Tetsuo TAKEDA, Yoshihiro HISHIKI
A new type cable-stayed bridge has been invented: the girders are steel pipes, filled with concrete whose volume depends on the span position, and composite with concrete slab. The static and dynamic characteristic has been studied for a model bridge with main-span of 900m. It is found that a new system has a good balance of deflection and sectional forces, and the composite pipe girders can be designed by RC method, which has been verified by the bending tests. Dynamic study has shown that a new system has the same strength against wind forces as existing long span cable-stayed bridges. The new system has also been proved feasible on detail design and erection procedures.