Determination Of Cable Force Of Cast-in-place Prestressed Concrete Cable-stayed Bridge

The quality of cable-stayed bridge internal force distribution is an important criterion to measure the advantages and disadvantages of the design and construction, and the cable force is the core factor affecting mechanical properties of the cable-stayed bridge, with characteristics of "pull one cable and move the whole bridge". Therefore, the determination and optimization of cable force is a key problem in the construction of cable-stayed bridge. This paper will be based on the existing research results, taking the Chaohu tourism avenue cast-in-place Hangbu river bridge as engineering background, and using influence matrix method to determine the cable force of the Hangbu river bridge under reasonable finish state and construction state. This research has the important theory significance and practical engineering value.In this paper, the main research work includes:1. It establishes the finish bridge mode and bracket cast-in-place construction mode of Hangbu river bridge by using finite element method. It has a deep understanding to the Hangbu river bridge by the bridge static and dynamic analysis.2. It introduces influence matrix method and influence matrix-based comprehensive method to determine the cable force of cable-stayed bridge. This paper uses the two methods compared to determine bridge cable force. It respectively the rigid support continuous beam state, or the bending energy minimization as the goal, to meet some control section internal force and displacement, and considering bridge dead load, prestressed and other factors. Using this method and finite element model can well determine reasonable bridge cable force of the Hangbu river bridge.3. It discusses the forward iteration method based on influence matrix to determine construction cable force. According to the characteristics of bracket cast-in-place, this paper gets bracket-off factor method based on influence matrix to determine reasonable construction cable force. It uses the bracket-off factor, bracket influence matrix, no bracket influence matrix to modify the system influence matrix, which can greatly improve computational efficiency. Combining finite element model and numerical analysis tool, and determining the reasonable construction cable force of Hangbu river bridge by using this method.