Construction Control Of Steel Box Girder Cable-Stayed Bridge

Now,there are many reseach results in determining the finished state and construction state and in construction controlling of cable-stayed bridges. However there are still a lot of problems in the application. Base on the project of South and North Channel cable-stayed bridge of Hang Zhou Bay Sea-crossing Bridge,the paper has done many studies in these three aspects and come up with an integrated method for steel box girder cable-stayed bridge:The idea that the inner force need not be in balance stage of cast-in-place constrution stage for the cable-stayed bridge which have system swich in order to determine object finished stage is introduced;The idea that the rational finished stage should be determined with rational construction stage is introduced;An synthesize method for determining the resonable finished state of cable-stayed bridges is introduced.Conclusion shows:The synthesiz method is easy to be used for all cable-stayed bridge which have system swich.The formula of calculate the welding line width for cantilever constrution steel box girder cable-stayed bridge is deduced; The idea that the total displacement of the girder should be chosen as control parameter, and strictly controlled when forward-iteration is used is introduced; The method of calculate the length of stress-free cable is discussed. Conclusion shows:The forward-iteration could be applied for steel box girder cable-stayed bridge if proper control parameter and coefficient is chosen;The method used for calculate the length the stress-free cable which based on parabola theory is convenient and has enough precision if the cable length less than 350m.The sensitivity of parameter of cantilever constrction of steel girder cable-stayed bridge is analysed; Based on construction control theory in existence, the method that self-adaptive construction control used in forepart and feedback construction control used in afternoon is introduced; The special problem in construction control is discussed. Conclusion shows:The key of the construction control of the steel box girder cable-stayed is the control of temperature effect which should be avoided; The control method for steel girder cable-stayed bridge is convenient and valid; The problems which are arosed by temporary concretion and the dissimilar shrinker of the welding line shoule be solved by proper measure.