Anqing Railway Yangtze River Bridge To Mechanical Performance

Anqing Changjiang River Bridge is a six-span continous steel truss girder cable-stayed bridge with span arrangement (101.5+118.5+580+ 217.5+159.5+116)m. It is a railway-exclusive cable stayed bridge with the longest span in China up to now.Orthotropic integral steel bridge panel structure is adopted for the bridge floor system, the stress situation is complicated. The mechanical characteristics of the bridge are studied in this paper, the main research tasks are as follows:1,The FEA simulative method for the extra large steel truss cable-stayed bridge with orthotropic integral panel is studied. Two different FEA models for the whole bridge are established to calculate the dead load case and the worst-case of living load together with additional forces case respectively.2,The mechanical properties of the whole bridge under dead load,worst-case of living load,combination load of all kinds of main forces are studied. The results show that:the deflection-span ratio of the bridge under worst-case of living load is 1/732; the rigidity of the bridge satisfies the requirements; the main trusses,steel panels,pylons and cables satisfy the design specifications when the combination load of all kinds of main forces acts on the bridge.3,The mechanical properties of the whole bridge under additional forces (including temperature load,wind load,train braking load) are studied, the results show:temperature load and wind load affect the lower chords,girders and the cross beams a lot, but other members of the bridge slightly. Train braking load affects the internal forces and displacements of the bridge slightly. All members of the bridge are within the design bounds when the main forces and additional forces act on the bridge together.4,The cable weight and the cable sag effect are studied in this paper, the results show:for a cable-stayed bridge with such an extra span as Anqing Changjiang River Bridge,cables are very heavy, weighing as much as 4300 tons, thus they affect the deflection of the bridge significantly, which shoud be counted into consideration; the cable sag effect influences the structure stress and deflection slightly.The research results of this paper provide basis for the design of Anqing Changjiang River Bridge, and it is also of reference value for other similar huge and complicated cable-stayed brige of steel-concrete composite structure.