Mechanic Behavior Research Of Single Tower Cable-stayed Bridge Hybrid Girder Under Dead Load

As the improving of people's living standards and the developing of science and technology, hybrid girder cable-stayed bridge is showing strong vitality due to its unique structure and technical characteristics, and it is widespread used abroad. Compare with other types of bridge, hybrid girder cable-stayed bridge is different from them as: there are two different materials used in main span and side-by span, just as side-by span girder is built in prestressed concrete and main span girder is built in all steel or partial steel. This kind of cable-stayed bridge make the arrangement of span and the golbal force reasonable.Base on DongSha bridge in the eastern of GuangZhou city, this paper build global bridge model to analyse the global force of the girder and the tower in the status under dead load, and then fix the rational ratio of main span and side-by span, and furthermore, the local model of mixed segement in the girder where the materials are changed is built analysis the local stress status. Researching the mechanic behavior of hybrid girder, The main research work covers the following aspects:1,This paper build finite element model of DongSha bridge to analyse the global force status of its girder, and calculate boundary condition for the fallowing local simulated analysis of mixed segement.2,The research of feasible ratio between main span and side-by span: According to the result of global bridge simulated analysis and the measured data, the paper analyse the force status of side-by span built in concrete in the status of perfect dead load, and deduce rational ratio of main span and side-by span with parameterized form.3,The research of local stress in steel and concrete mixed segment Using of local space finite element entities model and combine with the measured stress data during the constrction control, the paper analyze and research in detail on the mixed segment in the status of different loads.4,Through pre- imbedmenting the strain sensors and the temperature sensors, the paper measure the stress and the temperature status of mixed segment during the constraction, and then research the local temperature effect of steel and concrete mixed segment by the measured date.