Study On Construction Monitoring Of Prestressed Concrete Continuous Beam Arch Bridge

With the rapid development of high-speed railway,more and more bridge structures are used in engineering construction.Prestressed concrete continuous beam arch bridges have been widely used in practical projects because of their unique advantages,such as more reasonable structural forces,relatively low requirements for foundation,reduced building height and overall concise and beautiful.Construction monitoring technology guarantees the safe construction and construction quality of the prestressed concrete continuous beam arch bridge.At present,the main construction monitoring methods include post-control method,predictive control method,adaptive control method and maximum tolerance method.This paper adopts adaptive control method to compare them comprehensively and establishes construction control system based on it.Based on the practical engineering background of a pre-stressed concrete continuous beam arch bridge(90+180+90)m,using the finite element analysis software Midas Civil,this paper defines the material,concrete shrinkage and creep,load and boundary conditions in the construction stage,and divides the construction stage.Based on this,a complete finite element model is established.Through calculation and analysis,the displacement and stress in each construction stage of the bridge are obtained.Theoretical value.In this paper,the influence of different closure schemes on the prestressed concrete continuous beam arch bridge is elaborated from three aspects of linearity,stress and internal force through finite element analysis.Considering the influence of the pre-tensioning force of the rigid skeleton and the temporary beam on the bridge closure,the stress state of the rigid skeleton in the middle span closure section and the pre-tensioning force of the temporary beam are obtained by theoretical calculation.At the same time,the temperature effect of the cantilever stage of the prestressed concrete continuous beam arch bridge is analyzed,and the analysis results are obtained based on the finite element software.Combined with the measured data,the data support is provided for the cantilever construction and closure section construction of the bridge,and the reliable guarantee for the precise closure of the bridge is provided.In the concrete construction monitoring implementation of the prestressed concrete continuous beam arch bridge,this paper firstly analyzed the data of hanging basket preloading,and fitted the approximate curve of load-displacement with the least squaremethod.Combining with the measured value of the hanging basket deformation in each construction stage,the theoretical value of the hanging basket deformation was constantly adjusted,and finally the ideal deformation value of the hanging basket was obtained.By comparing the field monitoring data with the theoretical values of finite element software analysis and calculation,the deviation of alignment and stress is obtained.The causes of the deviation in construction are analyzed and adjusted.The alignment and stress of the bridge have reached the expected value.