Determine The Reasonable Cable-stayed Bridge To Bridge The State Of Stress Optimization Method

As we know, the cable-stayed bridge consists of three main components: the beam, the tower and the stay-cables. The existence of the stay-cables gives more design freedom to the designer, meantime, leads the bridge to a high order statically indeterminate structure. Thus, even a tiny change of the stay-cables may cause a significant change of the beam. The determination of the cable force becomes a key issue in the design of the cable-stayed bridge.This paper, based on the existing researches on cable-stayed bridge, centers around the calculate methods for rational cable force, which can be summarized as follows:(1) At first, the research results about cable force optimiaztation both at home and abroad are reviewed, and then the present situation of cable force optimization is preliminarily analyzed, and the optimization principle of cable-stayed bridge is concluded in the paper.(2) Three methods, the continuous rigid-support beam method, minimal energy method constraining cable force only, and minimal energy method constraining both cable force and moment of mid-span are applied respectively to buid the cable adjustment model, and ralated programes are compiled to calculate the cable force of the E-Huang Yangtze River Bridge.(3) Based on the existing optimization methods, a new method named constrainted minimal stress opimization method is proposed, which takes the stress of the stay-cable, the beam and the tower under the effect of dead load and live lode.as the constraints, while the total area of prestressing tendon which every beam element needs as objective function and uses constrained variable metric method to solve the equation. In the paper, this method is applied to calculate the cable force of the E-Huang Yangtze River Bridge.(4) Compared with those from the other three optimization methods, the results figured out in the optimization method proposed in the paper appear to be more reasonable, and the method is feasible and has higher value of engineering application.