Force Bearing Properties Analysis Of Cable-Stayed Bridge With Plate-Truss Composite Beam

The side spans of MinPu Bridge are made up of chord beam with concrete encased shaped steel, steel vertical web member, steel inclined web member, steel batter brace, prestressed concrete cross beam and concrete bridge deck slab. This is a relatively novel plate-truss system-composite structure truss system. This structure system has not been reported at home and abroad and no references are available about this kind of bridge. Bridge engineers and design department want to comprehensively understand its property of force bearing.In this paper, MinPu Bridge is selected as an example. ANSYS software is used to build the whole bridge model, a segmental girder model and a joint model of chord to analysis force bearing. Then, the experiment of a joint model is designed.The result of analysis shows that: The stress of steel chord and steel batter brace is low. The stress of steel vertical web member and steel inclined web member is high. The biggest stress lies in the member beside the bridge pier. The stress of concrete in the beam is uniform. There is stress concentration in the interface between steel truss and concrete. The stress on the gusset plate is high at the corner between steel vertical web member and steel inclined web member. The stress is not uniform in the steel vertical web member, steel inclined web member and steel batter brace. There is big moment in the steel member. Form the results of welding stud analysis we can conclude that the force on welding stud of gusset plate is not uniform. The welding studs with big force concentrate the first three rows.