Passenger Line Long Span Steel Box Tied Arch Bridge Test Research

The tied arch through bridge is one of the ideal structure type because of its good-span capacity, low-height of architecture, convenient construction, beauty and economy , when the high speed railway skew overpass the main roads of the city and expressway. A steel tied arch through bridge with 140 meters span skew overpassing the Beijing-Zhuhai Expressway uses the semi-composite floor system. In this paper, the origin, development and application of the tied arch bridge on the railway were introduced and the reduced-scale model experiment of this bridge was completed. The main work are as follows:1. A reduced-scale model of 1:8 was made according to the similarity theory, moreover the accessorial loading device was designed and the project of loading was corroborated.2. Four experiments of the steel structure were completed which was used to simulate the condition that the concrete slab was failure. By analysing the results of experiment and the results of finite element analysis, the deformation and loading-carrying behavior of the structure were studied, and the mechanical behavior of the structure was evaluated.3. Five experiments of the steel-concrete composite structure were completed. By analysing the results of experiment and the results of finite element analysis, the deformation and loading-carrying behavior of the structure were studied, and the mechanical behavior of the structure was evaluated. The bearing capacity of the structure was studied based on overload experiment of the five.4. The influence of the compoist concrete deck on mechanical behavior of the structure was studied based on the two stage model experiments. The results show that: the compoiste deck enhances the whole stiffness of the structure, and improves the mechanical behavior of the floor system.5. The mechanical behavior of the bridge were studied based on model experiment and theoretical analysis of the actual bridge.The achievement of this paper can service design of this bridge and provide references for other similar structures.