Local Stress Analysis Of Concrete Around Cable Saddle In Short-Pylon Cable-Stayed Bridge

The short-pylon cable-stayed bridge is one of new bridge structures, which has been developing in recent 20 years. It has the structural characteristics of both cable-stayed bridge and continuous girder bridge. The structure also possesses the very strong competition for bridges with span of 100～300m, so the structure has well potential development.For the short-pylon cable-stayed bridge, cables are anchored in the pylon directly, or through the top section of the pylon and then anchored in the main beam of the other side of the pylon. At present the strand-separating tubular-saddle is becoming mature gradually, and is applied widely in the short-pylon cable-stayed bridge. The configuration of strand-separating tubular-saddle is somewhat complex, and the contact between concrete and steel saddle is related to highly non-linear issue. Studying the distribution of the concrete stress around the saddle has important significance to pylon's design and the construction.Taking the Guangxi Liuzhou Jinglan Bridge as the project background, this thesis mainly studies local stress of concrete near the strand-separating tubular-saddle. The primary contents are as follows:1. Summing up and contrasting the differences, advantages and disadvantages of the pylon structures between conventional cable-stayed bridge and short-pylon cable-stayed bridge;2. Carrying on the statically analysis for the short-pylon cable-stayed bridge using plane finite element theory, and discussing the influence of the cross-section area of cable and the bending stiffness of girder to the static characteristics of bridge structure under the live load;3. Computing the local concrete stress around the strand-separating tubular saddle structure of the Jinglan Bridge by ANSYS, and Studying the distribution of concrete stress;,4. Taking the computation for reinforcing bars configuration in concrete pylon of the Jinglan Bridge by ANSYS, and discussing the relation between reinforcement ratio and concrete crack, providing Suggestions for reinforcement configuration and construction of the pylon.