Design of Steel Truss Girder Cable-Stayed Bridge of 567-m Main Span of Huanggang Changjiang River Rail-cum-Road Bridge

The main bridge of Huanggang Changjiang River Rail-cum-Road Bridge is a continuous steel truss girder cable-stayed bridge with double pylons and with span arrangement(81+243+567+243+81) m and is a cable-stayed bridge structure of semi-floating system.The upper deck of the bridge carries 4-lane expressway and the lower deck carries double-track railway.The main girder is of the inverted trapezoidal section that is wide at the upper part and narrow at the lower part,the webs members are inclinedly set with the inclination ratio being 1∶2.7 and the main trusses are designed as the ones of normal N-shape.For the roadway deck,the deck is the integral orthotropic steel deck supported on the stringers and cross beams while for the railway deck,the deck is also the integral orthotropic steel deck,but is supported on the multiple cross beams.At the upper chord panel points of each main truss,the lateral bracings are set.The pylons of the bridge are the H-shape reinforced concrete structures.The stay cables are arranged into the spatial double cable planes.The anchoring systems of the cables at the deck level are set in the upper chords of the main trusses.The bridge is erected by the cantilever erection method of piece-by-piece assembling.To cope with the difficulties of the cantilever erection of the inclined main trusses,the web members are assembled and connected outside the panel points.