Construction Monitoring Research Based On A Long-span Concrete Girder Bridge

Since the prestressed concrete beam used in bridge construction from the nineteen thirties,it has greatly promoted the development of large span continuous beam bridges construction and the construction technology of bridge plays an important role in bridge cross section type of molding selection,In this paper,Taking the Beijing-shenyang passenger dedicated liaoning period of TJ-13 Xinglong store extra large bridge in a typical long span continuous beam bridge as the engineering background,the large span prestressed concrete continuous bridge at the cantilever construction key technologies are discussed,and obtained the preliminary research results for this kind of bridge,the construction provides the reference.Mainly as fllows:(1)Summarizing the large span prestressed concrete continuous beam cantilever construction technology,including the template installation,steel bar,box girder concrete pouring,curing of concrete,prestress tension,pressure grouting,cross beam in the successful closure construction process etc.key problems,It ensures the construction quality of construction for similar project.(2)Based on the construction of Xing Longdian Bridge,build the finite element model with ANSYS,analyze the shrinkage and creep of concrete and the pre-stressed load about the bridge structure.According to the actual situation of the bridge,give a reasonable program,develop a construction control processes,establish a comprehensive and effective control system,and develop a hierarchical solution.Observe the deflection,temperature and stress of the bridge.Besides,the quality of the materials,the size of the box beam,and the pre-stress should be taken into accountant.Then compare and analyze the data surveyed from the bridge,make the difference of the site and model.Find the reason of the difference combined with the theory to adjust the parameters and predict the changes of the bridge.At the same time,the calculation method of structural stability and safety and method of big cantilever for passing winter are also introduced.(3)According to the monitoring results of Xing Longdian Bridge,compare the deflections in every stage with cumulative deflection and the stress of every point between calculation and survey.Take a conclusion that the monitor plays an important role in the process of bridge construction.