Research On Mechanical Behavior Of Steel-concrete Joint Section Of Asymmetric Hybrid Girder Cable-stayed Bridge

Recently,the quantity of hybrid girder cable-stayed bridges is increasing continuously.As the key of hybrid girder cable-stayed bridge,the design principle and mechanical behavior of steel-concrete joint section has drawn researchers' attention.Based on existing research,taking Nanxi Changjiang Highway Bridge as the engineering background in the thesis,integral model combines with partial model are used to research on mechanical behavior of steel-concrete joint section of asymmetric hybrid girder cable-stayed bridge.In the meanwhile,adopting controlling variable method to reveal the law of mechanical behavior caused by the change of structural parameters,giving optimized advice of structural design.The main research work of the thesis are as follows:(1)Introducing the development history and structural features of the hybrid girder cable-stayed bridge,making an abstract of recent research of the hybrid girder cable-stayed bridge in a few aspects,such as theoretical research,simulating method and design details.(2)Establishing the integral model of Nanxi Changjiang Highway Bridge with the software MIDAS/Civil,comparing the mechanical behavior of symmetric and asymmetric model of Nanxi Changjiang Highway Bridge,confirming the reasonable site of steel-concrete joint section,calculating the mechanical behavior of the whole bridge under the ultimate limit state and the serviceability limit state,summarizing the value of axial force,shear,moment and torque in each state.(3)Establishing the partial model of Nanxi Changjiang Highway Bridge with the software ANSYS,calculating the mechanical behavior of every steel plate and concrete block of steel-concrete joint section,summarizing the regular pattern of mechanical behavior of steel-concrete joint section.Compared with the steel-concrete joint section of Wuhan ErQi Changjiang River Bridge,summarizing(4)Finding out the key parameters which obviously affect on mechanical behavior of steel-concrete joint section in the existing research.According to the mechanical behavior of steel-concrete joint section,adopting thickness of bearing plate,length of steel compartment and thickness of web using beveloid plate as the key parameters,discussing the caused affection when they change in a certain range.