Research On Construction Control Of 64m Simply Supported Tied Arch Bridge In Yinxi Railway

In recent years,with the rapid development of high-speed railways in China,concrete-filled steel tubular arch bridges have been more and more widely used in practical engineering.The concrete-filled steel tubular tied arch bridge has beautiful structure,smooth shape and strong carrying capacity.It is suitable for a variety of complex engineering projects and has a large spanning capability.In the construction process of CFST tied arch bridges,the conversion of multiple construction stages is involved.The key control items in the construction process are different from the construction of ordinary concrete arch bridges.The construction control research on the construction process of this type of bridge has important engineering significance for reducing construction errors,ensuring construction accuracy and reducing post-operation and maintenance costs.In this paper,the construction control of CFST tied arch bridge is studied.The 64 m simple-supported CFST arch bridge in Lingwu Yinxi Railway Interchange Bridge is taken as an example to design the construction control of simply supported CFST arch bridge.The construction technology and control method were studied.The mechanical properties of the key processes were analyzed,which provided some reference basis for the construction scheme design,construction calculation and construction control of the CFST tied arch bridge.The main research contents of this paper are as follows:(1)A lot of literatures were reviewed,and the research purpose and significance of the construction control of simply supported CFST tied arch bridges were introduced.Based on the research of domestic and foreign scholars,combined with the engineering environmental conditions,structural form,construction process and construction steps of the bridge site,the key construction nodes and key structural parts of the simple-supported CFST tied arch bridge construction are studied.Tasks and content of construction monitoring.(2)Taking the 64 m simple-supported CFST arch bridge in Lingwu Yinxi Railway Interchange Bridge as the engineering background,the finite element analysis software Midas/civil is used to establish the spatial 3D model,and the pre-camber setting method and calculation process of this kind of bridge are developed.Explain and propose key technical measures for pre-camber setting in actual engineering.(3)The spatial finite element model is used as the basic calculation tool,and the structural components of the simply supported CFST tied arch bridge are simulated and calculated in combination with relevant specifications.Considering the construction stage analysis of the beam,the erection of the bracket,the tension of the prestressed steel bundle,the installation of the rib and the tension of the boom,the bridge deck pavement construction,and the operational state to calculate the deflection of the tie beam,and obtain the wholeconstruction process.The calculated value of the deflection is calculated based on the calculated value of the deflection,and the pre-camber value of the bridge structure is calculated.(4)By setting elevation and stress monitoring points on the main beam and the arch rib,the actual structural elevation and the stress values at different positions of the structure during the actual construction process are measured,and the measured stress and elevation values are compared with the elevation and stress theoretical values to obtain the construction control.in conclusion.(5)The main arch ring concrete compactness test.Ultrasonic detection method is used to monitor the compactness of concrete,the test results are analyzed,and the discrimination conditions of concrete compactness are compared to obtain the conclusion of concrete compactness test.