Research On Concrete-filled Rectangular Steel Tube Truss Structure In The Continuous Rigid-frame Bridge

Concrete-filled steel tube truss bridge has more and more been relied by the majority civil engineering designers for its light weight, convenient construction, low cost and good mechanical properties. In China, Zidong Bridge in Nanhai of Guangzhou, Xiangjiaba Bridge in Hubei and Wanzhou Bridge in Chongqing are concrete-filled steel tube truss bridges which are used with concrete-filled steel tube. Comparing to the circular steel tube, rectangular steel tube has many advantages,such as easy to be cut, simple node structure, convenient construction, easy to be connected with the bridge deck and bending stiffness, etc. Base on the concrete-filled steel tube truss bridges which have been built and the domestic and foreign scholars'studies of the rectangular concrete-filled steel tube, this paper propose a new kind of concrete-filled steel tube truss bridge.In this paper, a research work mainly focus on the following aspects:①The mechanical characteristics of the concrete-filled steel tube structure, especially the rectangular concrete-filled steel tube structure, and have been built of the concrete-filled steel tube truss bridge are introduced, propose a rectangular concrete-filled steel tube truss bridge in the potential applications.②The structure of the steel truss bridge was introduced, the concrete-filled steel tube truss bridges was analyzed, which have been built.③The rectangular concrete-filled steel tube's truss and nodes'type and selection of the calculate model are systematic analyzed, which provide a very good basic of trial design theory for the rectangular concrete-filled steel tube truss continuous rigid frame bridge.④Taking the Yuexi River bridge as the engineering background, try to design a kind of same span of small eccentric and large eccentric rectangular concrete-filled steel tube truss continuous rigid frame bridge, analyze the ultimate bearing capacity of construction process and in the bridge state, and get a reasonable force mode of the rectangular concrete-filled steel tube truss continuous rigid frame bridge.⑤Node is a key force part of the truss bridge, that determines stucture behavior of the overall truss.This paper try to design a suitable node of the rectangular concrete-filled steel tube truss continuous rigid frame bridge, and check its ultimate limit state and the node intensity of welding.Through the design of the rectangular concrete-filled steel tube truss continuous rigid frame bridge's stress analysis, economic comparison and node design, we can see that the rectangular concrete-filled steel tube truss continuous rigid frame bridge is a feasible bridge program of reasonable force, convenient construction and a good economic bridge structure form.