The Bridge Reinforcement Research Of Large-span Reinforced Concrete Box Arch-bridge Based On The Section Increasing Method

In our country mountainous area highway,reinforced concrete box arch deck at around 100 m span has strong competitiveness.Reinforced concrete box arch has low cost,high bearing capacity,low maintenance cost,the advantages of its construction process of big stiffness,good stability,as a bridge for the box section flexural torsional stiffness after big,box arch section hollow out rate can reach fifty percent to seventy percent,compared with the plate arch can be much less masonry volume,weight,save the cost of top and bottom structure.Its defect is due to the tensile strength of concrete is low,not using prestressed system insufficient durability.General damage of reinforced concrete box arch arch ring main cracks and deformation,the main arch ring,abdomen arch,transverse coupling deformation displacement,vertical wall or column tilt and lower the structure of the disease.As a result,the bearing capacity of the determination of accurate evaluation and reinforcement scheme to improve the bearing capacity and prolong its service life,and become the bridge researchers need to solve the problem.In this paper,a hole on the clear span 150 m bearing type of reinforced concrete box arch as engineering background,first load test method is used to its carrying capacity evaluation,and then select the enlarged cross section method to reinforce,then the inspection by load test of reinforcement effect.Research has reference significance for reinforced concrete box arch reinforcement.The research content is as follows:(1)The dissertation firstly the background engineering arch bridge are analyzed in detail the components of disease,comprehensive evaluation of bridge.In order to further the technical conditions and carrying capacity were accurately assess,formulate load test program,through the analysis of the static and dynamic load test results of bearing capacity of the bridge.(2)Considering the actual traffic conditions to improve the bridge load level,assess the carrying capacity of the bridge arch ring.Put forward after comprehensive comparison of the arch ring by increasing section method,and USES the software MIDAS/CIVIL construction stage model is established,the system simulates the process of reinforcement,on the basis of the results of the analysis put forward reinforcement scheme in detail.(3)The loading test method is adopted to reinforce the arch bridge,the static and dynamic performance evaluation results show that not only the static performance of the improved structure,its dynamic performance is improved significantly,visible for reinforced concrete box arch reinforcement enlarged cross section method is most effective.