Cantilever Construction Control Of Continuous Girder Of Over-railway Bridge Of Longkui Road

With the swift development of economy and improvement of bridge construction technology in China, more and more bridge is being built. Prestressed concrete continuous girder bridge is one kind of bridges in common use and always be construct with cantilever construction method. Because of the influence of the material density, elastic modulus, section size shrinkage and creep of concrete and other factors, stress and transformation in various stages deviate from its intended state during the construction of the bridge, that make bridge suit smoothly approach difficulty. Therefore, in order to ensure the successful closure of the whole bridge and the bridge alignment and stress state, it is very necessary for accurate monitoring of bridge structure state in the process of bridge construction.In this paper, the current situation, the aim and the significance of construction monitoring are described, then the method and content of construction monitoring are summarized. Pre-compression experiment and general construction scheme are described in detail in this paper. Pre-camber of the bridge floor is get, part of the internal force and deformation of construction stage are analyzed by using the finite element software such as Midas, Dr.bridge, establish the finite element model of Longkui Road Over-Railway Bridge. It Achieved good results in the construction control process using the least square method for the identification and correction of density and elastic modulus.Monitoring results of the project of Longkui Road Over-Railway Bridge are analyzed in this article, the real deflection displacement and stress of segments are accordance with comparing. The results showed that the ultimate control of this bridge have reached an anticipative goal in smooth linear and reasonable structure stress.