Simulation And Stress Monitoring Analysis In The Overall Push Process Of Kongli Huaihe Large-span Steel Structure Bridge

The overall push construction technology in the long-span continuous arch bridge in the application of relatively small,you can access the information is relatively small.In addition,the long-span continuous arch bridge in the push process,due to the main bridge structure of the boundary conditions continue to change,resulting in structural system force is also extremely complex and changeable.Therefore,in order to ensure the safety and smooth progress of the overall push process,stress monitoring of the various components of the main bridge is very important.Taking the overall push of the main bridge structure of the Kongli Huaihe River Bridge as the background,based on Midas Civil finite element software,this paper simulates the overall push construction process of the three-span continuous beam arch combination system arch bridge used in the main bridge structure.According to the simulation results in the field,we arrange related measurement points and get the measured data.According to the stress results compared and analyzed,we can find out the most unfavorable stage of the main bridge structure,the maximum position and the size of the corresponding section stress,and the stress variation law of each structural member in the whole process of the three rounds.These are able to provide more reference for the arch bridge arch of the same type in the same type,and provide new ideas and directions for the whole push construction of the same type bridge.The paper mainly does the following work:Firstly,the construction scheme and the overall pushing process of the main bridge structure of the Kongli Huaihe River Bridge are studied.The structure made of three-span steel box under the continuous tuck arch,its three spans are110 m + 180 m + 110 m.Its structure is mainly composed of three systems: arch rib system,rigid tie bar(steel box girder)and flexible tie rod(external prestressed)system,boom system.The structure is pushed in three rounds.Secondly,based on the Midas Civil finite element software,the finite element model of the main bridge structure is established and the construction of the whole jacking process is defined according to the arrangement of the main bridge structure and the overall push construction program.Thirdly,the simulation results are extracted by simulating the scheme.The stress envelope of the main components of the main bridge structure is extracted from the three-wheel pushing process.The most unfavorable section position,the corresponding pushing-out stage and the most unfavorable section stress value of each component are found.Fourthly,according to the simulation results in the field we layout strain sensors,collecting the measured results.Through the monitoring process of the whole construction process,the stress control of the whole roof pusher construction is realized,and the actual force of the structure of the main bridge structure during the whole construction process is monitored.Fifthly,the simulation and measured stress values were compared and analyzed.Through the measured stress of the pusher structure in the first,the second round and the third round of the push-off process compared with the simulated simulation results,it is found that the stress curve of the two models is high,the stress state of the structure is in line with the design requirements,and the established Midas Civil finite element model can well simulate the mechanical performance of the components during the jacking process.