Tribute River Bridge Construction And Control Of Pre-camber Uncertainties

More and more requirements were put forward to the current construction control technology, because new, larger bridge engineering emerging. Due to the influence of the bridge construction with many and complex factors and there are uncertain parameters estimation so much that bridge construction control technology will change as engineering different features.This paper based on the background of GongJiang bridge engineering, research in creep and shrinkage of concrete,prestress loss and temperature changes impact ofconstruction precamber of bridge, in the process of cantilever construction. Consider the concrete ages, humidity, start loading time, composition material, and other factors, established concrete shrinkage and creep finite element model of the GongJiang bridge 0-5 pieces, forecast the deformation and internal force that caused by concrete shrinkage and creep in the process of construction of box. Cause difficulties that in bridge sucessfully to fold because the shrinkage and creep of concrete, and set construction precamber smaller.Amended the prestress loss calculation method of GongJiang bridge of the upper structure, practice proves calculation method is reliable, better meet the prediction of prestress loss.Analyse the influence of prestress loss that caused linear and construction percamber change in the process of GongJiang bridge 5 box girder structure construction. According to bridge's 0 # block to 5 # block construction conditions, establish finite element model of cantilever construction, forecast the prestressed loss in the process of cantilever construction, for cantilever construction precamber control offer support.Combined with the actual conditions of GongJiang bridge, decided calculation method of temperature field distribution and temperature stress that happended in GongJiang bridge box beam structure. Establish finite element model of main piers 0 # block, consider the influence of concrete hydration heat, sunshine radiation and temperature change in the process of bridge cantilever construction, to analyse and calculate bridge structural deformation and stress, provide the basis for determination of the construction precamber.Comprehensive consideration of the influence factors that to construction precamber, put forward the calculating formula of cantilever construction precamber, proved the calculating formula of construction precamber is applicable by practice.