Key Technology Research On The Construction Of Main Girders Of Steel-tube Concrete Tied Arch Bridges

With the rapid development of steel pipe concrete arch bridges,under-bearing steel pipe concrete tied arch bridges are widely used in bridge engineering and have become an important part of modern bridge construction.The main girder can not be erected full support to carry out the construction,for the above problem,through reading the literature and establishing model analysis,the main research results of this paper include:1.Using the finite element software Midas Civil to establish the spatial finite element model in the construction stage,the structural internal force and deformation data of the arch ribs and tie beams in the key construction stage are summarized,and the performance of the main girders in the operation state after ten years of completion of the bridge is analyzed considering the effect of concrete shrinkage and creep,and the reasonable construction state of the main girder structure is given.2.Based on the construction environment and temporary construction support design requirements,a temporary support system was designed and selected based on the combination of Bailey beams and steel pipe piles.A three-dimensional truss analysis model was created using finite element analysis software,considering the actual load conditions in the project.The main load-bearing members were grouped and analyzed to verify their strength,stiffness,and overall stability under construction loads,ensuring the safety of longitudinal beam construction.3.The design of the beam lifting system and the technical requirements of the site construction are proposed,the construction of the suspension assembly of the middle crossbeam is considered and the design of the suspension bracket is carried out,the rod models of the suspension bracket of the middle crossbeam and the special suspension bracket of the end middle crossbeam are established respectively,and the calculation results of the main rod of the bracket under the actual load are obtained to meet the site construction requirements.4.propose construction technology methods for arch rib construction and boom construction of steel pipe concrete arch bridge,mainly including arch rib infusion process and boom adjustment and tensioning,and clarify the main construction technology points to meet the complex environment construction conditions.The above research is aimed at studying the key technologies for the construction of steel pipe and concrete tied arch bridges and proposing targeted analysis methods and technologies suitable for the construction of such projects.