Study On The Force Analysis And The Modal Test Of The Steel-Concrete Composit Cable-Pylon Anchor Structure Of Cable-Stayed Bridges

The construction of the long span cable-stayed bridges of China is developed rapidly in recent years. Large numbers of long span cable-stayed bridges are successively constructed in all parts of our country. Because of the advantages of the cable-pylon anchor structure with steel anchor box such as the define forces and the convenience of construction, this structure is applied in many long span cable-stayed bridges.The thesis, based on the building Jiayue cable-stayed bridge, makes some test and research on the forces and the interrelated problems of the influence on the forces. The main contents are as follows:Firstly, the anchorage structure type of the cable-pylon anchor area on cable-stayed bridges and the current situation of the researches on the forces of cable-pylon anchor structure are introduced.Secondly, based on the analysis of the test results of the full size modal of cable-pylon anchor structure of the Jiayue cable-stayed bridges in Chongqing, the stress results of the cable-pylon anchor structure with steel anchor box under the load of 1 times and 1.4 times and the relative displacement between the steel anchor box and the pylon are obtained. The transferring mechanism of the load is also summarized. The test results indicate that the strength of the longitudinal slab, the lateral slab and the shear studs of the steel anchor box satisfies the correlative codes.Thirdly, the finite element analysis procedure ANSYS is used, combining with cable-pylon anchor structure of the real bridge, to build different finite element modals. At the same time the contrastive analysis between the theoretical calculation results and the test results is carried. The analysis shows that the theoretical analysis method of the single segment finite element modal with shear studs is reliable and effective. However, there exists some differences between the theoretical calculation results and the test results on the centralized stress of some areas in the modal. This method can be used in the qualitative analysis of the real bridge.Lastly, the finite element analysis is used to study the influences on the distribution rate of horizontal tensile force, the stress of the longitudinal slab of the steel anchor box and the stress of the control points on the pylon as the concrete elasticity modulus, the thickNess of the slabs of steel anchor box and the distance and the stiffness of the shear studs changes.