Design of Tieluoping Bridge on Shanghai-Chengdu Expressway

The main bridge of the Tieluoping Bridge on Shanghai-Chengdu Expressway is a prestressed concrete cable-stayed bridge with double pylons,double cable planes and with span arrangement(140+322+140) m.The basic section of the main girder of the bridge is the section of edge main girders and the pylons are the H-shape ones,each being 190.397 m in total height.The columns of a pylon were designed as the hollow pentagonal sections and in the anchorage zones in the upper parts of the columns,the U-shape prestressing strands were employed to reinforce the zones.A foundation for the pylon piers is composed of 24 nos.of 2.4 m piles.On both sides of a pylon,19 pairs of stay cables,made up of the low relaxation and high-strength galvanized steel wires,were arranged.Two kinds of the structural systems of the rigid fixity system of pier,pylon and girder and the floating system were compared from aspects of the temperature action,truck load action and stability coefficients of the completed bridge and eventually,the rigid fixity system that is more advantageous to the structural force conditions of the bridge was chosen.The software MIDAS Civil was used to respectively analyze the static and dynamic behavior,wind resistant stability and seismic response of the bridge.The results of the analysis indicated that the structural force conditions could meet the relevant requirements in the codes.The main girder of the bridge was constructed by the cantilever cast-in-situ method and the sequence of closure of the bridge proceeded from the side spans first and the central span late.