Bracket Cast-in-place Span RC Box Arch Bridge Construction Monitoring Research

As traditional bridge type，reinforced concrete box arch bridge has been built in alarge proportion of the bridges, and in the future for a long period of time, still has acompetitive edge in the mountains and other areas suitable for the construction of the archbridge. The large-span reinforced concrete archbridg with the bracket ring segmentcast-in-place construction methods, is hard to be constructed. In order to ensure the success ofbridge closure and bridge alignment, and at the same time control the internal force of thebridge within the permissible range of design allowables, construction and control work mustbe carried out in the process of bridge construction.Ring segment of cast-in-place construction box type of large-span arch bridgeconstruction process, the foundation settlement deformation and the strength,the stiffness andthe stability of the bracket are directly related to the main arch construction safety and themolding of the line shape of the arch. Based on a large-span reinforced concrete box archbridge project, through the establishment of the finite element model of the support structuresystem, the support structure were calculated and analyzed, determine the bracket system loadeffect, a clear benefit of its members discontinuity, and local member be reinforced, as well asbracket system discontinuity interest sections provide a scientific basis for monitoring.foundation bearing capacity were calculated and the lower limit was determined,and it guidedthe foundation treatment.When the main arch concrete pouring is completed and the strength reaches thedesigned requirements, the decentering of the main arch is a complex stress systemconversion process. Through modeling and analysis, one landing gear main arch will produceirreversible damage cracks, the bridge using cyclic way off the shelf off the shelf bycalculating, and achieved good results.After removing temporary supports, the main arch forms three times staticallyindeterminate structure. Some kinds of impact would be made on the internal forces and lineshape of the main arch by concrete shrinkage and creep. By modeling calculation, shrinkageand creep of concrete on the main arch of the axial force and stress has little effect, while themain arch of the moment and vaults deflection greater impact. Meanwhile, in the course of construction of the main arch bridge alignment controlmeasures are summarized, and the main arch bracket system and stress monitoring resultswere compared and analyzed to determine the internal forces of the bridge alignment and wellcontrolled. This content is available for the study of similar bridge construction and stressanalysis by reference.