Mechanical Characteristics Analysis of partially Cable-stayed Bridge

The main bridge over Zhanhe river at Pingdingshan is a two-span partially cable-stayed bridge with single stay surface and single short pylon. In order to analyse the mechanical characteristics of the bridge, a calculation model is set up by using the finite element analysis software ANSYS. The girders and pylon are respectively divided into discrete elements by applying 3 D linear finite strain beam element (beam188), and the tension cables are simulated by tension-only element (link10), when the model is established. The internal forces, natural frequencies and vibration modes of the bridge are calculated by applying the model. The calculation results show that, for partially cable-stayed bridge with the single pylon, the tension cables have significant influence on the axial force and moment of the girder. It can also be observed that the stiffness of the girder affects natural frequency of the whole bridge significantly and that the first several vibration modes of the bridge are mainly the vertical and horizontal vibrations. The results in this paper can offer the related technical parameters and basic data for the construction control and the health detection and maintenance within its service period.