Technology Research On The Cable Replacement Of Prestressed Concrete Cable-stayed Bridge

In the last 20 years, the cable-stayed bridge had a rapid development all over the world. However, as a result of the cable corrosion some of the cable-stayed bridge which built in the early years have damaged seriously. Although the designers have used a lot of cable-stayed bridge preservation measures, the anti-corrosion methods, techniques, materials and maintenance technology are unsuccessful in some extent. Although the cable-stayed bridge has some advantages such as spanning capacity, simple structure type , force clear, aerodynamic stability, structural lightweight aesthetic, the constraints about their cable service life vibration fatigue attenuation of degradation and corrosion of the two major factors have posed a threat and challenge to the durability of the structure. Nowadays, many cable-stayed bridges at home and abroad are facing the problem of cable replacement.The main objective of cable replacement design is to improve bridge geometry and internal forces of primary bridge by replacing cables. This article relys on the cable replacement engineering of a certain bridge of Nanchang .Firstly, basing on the bridge elevation and cable forces measured before cable replacement, using finite element software MIDAS and general structural analysis software ANSYS , the analysis model is built. Then , by means of cable forces adjustment and so on , making the cable forces of modeling approach the cable forces measured before cable replacement, according to the scheme of design, aimed at cable replacement process, simulation analysis is done , the calculated result is gotten. After the cable has been replaced, a detail analysis is made for the present statement of internal forces, based on which the cable forces is adjusted, using the cable forces optimization theory and minimal remnant energy principle. Finally, the correlative difficulties of engineering are summed up and discussed.