Simulation Analysis And Closure Technology For Continuous Rigid Frame Bridges Based On One-step Closure

With the advantage of large stiffness, small deformation, comfort for driving, easyconstructed and maintained, long-span prestressed concrete continuous rigid frame bridgesare becoming one of the most commonly used bridges in China. Construction technique ofcantilever casting method, with its set-up full framing, without the advantages of convenientconstruction economy has become the main construction method of modern continuousrigid frame bridge.At present, the more mature construction technology of long span continuous rigidframe according to the general "symmetrical cantilever, side span closure and midspanclosure" or "symmetrical cantilever to midspan closure, side span closure" the order of theconstruction, because of the long-span continuous rigid-framed span large, straight holenumber, statically indeterminate number is high, its bridge experience a long and complexstructure system conversion process, and, for a multi span continuous rigid frame bridge,the bridge into the order need long construction period, construction cost. A closure to makestructure more uniform, decrease The Times of system transformation for deflection controlduring construction period, with a compact reasonable force, short time limit, procedure,etc.Based on three-span, four-span and five-span long-span prestressed concretecontinuous rigid frame bridge, through finite element analysis software Midas Civil, finiteelement simulation analysisfocusing on the structural stress and deformation in bothconstruction stage and completion stage for an in-site long-span prestressed concretecontinuous rigid frame bridge is carried out in this dissertation, the method and effect ofjacking are studied and analyzed. In details, the following aspects have been studied in thisdissertation:(1)Literatures review for the study of continuous rigid frame bridges is presented andthe characteristic ofcontinuous rigid frame bridges is analyzed. The development trend ofthe continuous rigid frame bridge is summarized.(2)Utilizing the finite element analysis software Midas Civil, according to the actualconstruction processes, the simulation analysis is carried out for in-site long-span prestressed concrete continuous rigid frame bridge. Simulated stress and deformation datain both construction stage and completion stage is analyzed to check the structural stressand deformation during the construction. The stress and deformation of the structure in theconstruction process and after five years of creep and shrinkage of concrete are calculated.(3)The design principal for the stress and deformation during the folded pushingconstruction is summarized, and the influence of closure temperature value is considered inthe deciding of thefolded pushing force. The influence of the folded pushing force to thestructural behavior is analyzed in this dissertation.(4)The strength framework and balance weight designof closure are introduced andstudied.