The Analysis Study On The Structure Action Of A Single Pylon Cable-Stayed And Continous Rigid Frame Composite Bridge

The thesis takes the Xijiang grand bridge on the Guangzhou-Zhuhai High-speed Railway as background. The bridge is a composite bridge with single pylon cable stayed bridge and continous rigid frame bridge. From the bridge type, this thesis analysis the behavior of both of the cable and continous rigid frame in the composite bridge.Firstly, the model both of the composite bridge and the continuous rigid frame bridge without the cable simulating the construcyion process are established according to the actural construction process, invesigate the method of the establish model of privileged sites. Secondly, the thesis studies the structure behavior in construction process, and the effert on the structure behavior have been considered under kinds of condition such as concrete creep, shringkage and prestressing force. Through the analysis on the deformation of the bridge, the trend of deflection movement is gained, which is in the construction process the cantilever pouring segment. Through the analysis of the stress and deformation on the structure in the construction process, this thesis shows that the composite bridge is safety in construction stage, and the strength is enough, the deformation is reasonable. Meanwhile, this thesis compare and analysis the stress and deformation in each construction process between the two bridge styles, find the deflection of constrnuous rigid frame bridge without the cable is much larger than which of the composite bridge. Thirdly, the thesis studies the structure behaviors of the bridge in service stage, and loads under kinds of condictions are considered to analysis the bridge behaviors. Through the compare and analysis the two bridge styles, found the deformation and strength of the composite bridge is safty in each load combination, but the continuous rigid frame bridge is opposite. Through the compute and analysis of the structure action in construction stdge and underthe loads in kinds of conditions, the structure behavior of this bridge is very similar to the extradosed cable-stayed bridge, the cable could be regarded as the external prestressing with the continuous rigid frame main bridge.Lastly, the model of consolidation part of pier, tower and girder which stress is complexity is established with software ansys, put the boundary loads in entirely bridge compute to the verge of the model as the outside force. Then the press nephogram in this district can be elicited. The result indicate the press of the consolidation part of the pier, tower and girder is reasonable.Therefore, the structure behavior of cable-stayed bridge can be deeply understood, and the method to compute and analyze large-span concrete cable-stayed bridges can be learned. Meanwhile, this paper can be helpful for the construction and design of large-span prestressed concrete cable-stayed bridges.