Construction Control And Mechanical Behavior Analysis Of (90+180+90)m Continuous Beam Arch Bridge

With the rapid development of high-speed railway passenger trains,continuous beam arch bridges have become more and more popular among high-speed railway passenger trains due to their advantages of large rigidity,large span,good durability,and simple structure;in order to ensure that the construction of continuous beam arch bridges reaches The design anticipates that it is very necessary to carry out construction monitoring and control during the bridge construction process.This paper uses a(90+180+90)m continuous beam-arch bridge as a background support to monitor and control the stress,displacement and cable force during the construction of the superstructure of the bridge.The main researches are as follows:(1)Relying on the actual engineering background of the bridge,establish the bridge model and perform finite element analysis to obtain the theoretical calculation results of the continuous beam arch bridge at each construction stage;analyze the stress and deformation of the key section of the main girder and arch ribs of the bridge during the construction stage Value and change law,analyze the cable force value and change law of the boom in the construction process;(2)Develop a detailed and reasonable construction monitoring program for the main girder and arch ribs of the bridge.The construction monitoring program includes: in the cantilever construction of the main girder,the displacement of the main girder is monitored through the measuring points on the top of the girder,and the embedded strain Monitor the stress of the main girder;set displacement and stress monitoring points on the main girder and arch ribs to monitor the deformation and stress of the main girder and arch ribs;measure the cable force value of the boom;(3)Real-time monitoring of the bridge according to the established construction monitoring plan.In the cantilever construction of the main girder,the elevation and stress of the main girder are monitored in real time according to the set measuring points on the top of the girder and embedded strain gauges;after the main girder is closed,the main girder and arch rib displacement monitoring points are set to monitor the main girder.The deformation of beams and arch ribs are monitored in real time;strain gauges are used in the main beams and arch ribs to measure the stress of the main beams and arch ribs in real time;according to the suspension rod tensioning plan,the 72 suspension rods of the whole bridge are guided for cable tension During the entire construction process of the bridge,the stress and displacement of the main girder and arch ribs and the cable force of the suspender are monitored in real time to complete the entire process.Technical guidance of the bridge construction process.