Construction Control And Dynamic Performance Analysis Of Three-span Continuous Through Type Steel Arch Bridge

In recent years,the steel arch bridge is one of the main bridge types all over the world,owing to its obvious advantages,such as large stiffness,various style,beautiful form and short construction period.The linear and cable force can meet the design requirements by establishing a reasonable simulation model and monitoring scheme that guide the whole construction process and ensure the safety of the whole construction process.It is important to analyze the linear variation and stress characteristic in key construction stages in advance.As the continuation of bridge construction control,the dynamic performance of key component during bridge operation should be studied,The problem of deck vibration is also more prominent with the speed and the vehicle load,engineering accidents occur frequently in recent years,and the study of dynamic performance is particularly important.This dissertation is based on the north canal bridge in beichen district,tianjin city.The construction control of three-span continuous through type steel arch bridge was analyzed.Meanwhile,the effects of different parameters on the dynamic performance of the bridge during operation was studied.The main contents are as follows:1.According to the characteristics of the three-span continuous through type steel arch bridge,an appropriate construction monitoring scheme was proposed,and the stress of key component and linear monitoring points of the girder and arch was arranged.The finite element simulation model was established using Midas Civil,which provides the precamber of main girder,the precamber of main arch,the unstressed length of suspenders,the tension of the suspenders and the tensioning sequence,and the calculated results are used to guide the actual construction.2.By collecting the actual data of the key stages of construction,and comparing it with the theoretical data in the finite element model,analysing the cause of error and adjust it in time,to make it meets the requirements of the smoothness,the force meets the requirements of the design,the stresses meet the requirements of the standards,the reliability of the bridge simulation model and construction control method were checked.3.In order to analyze and calculate the impact of different parameters on the dynamic performance of the bridge,the three dimensional bridge model and vehicle model with 11 degrees of freedom were established using the MATLAB and ANSYS software respectively.The influence law of the dynamic response and impact coefficient of key parts of the bridge was obtained using the vehicle-bridge coupling method,including road roughness,lane,weight and speed of vehicle.4.The influence of temperature on the static performance of the structure was studied by considering the overall rise and fall in temperature,as well as the temperature difference between the main arch and the main girder.The results show that the temperature difference between the main arch and the main girder has great influence on the vertical displacement of the main girder,the deformation in the bridge deck caused by temperature difference was superimposed on the unsmoothness of bridge deck,the influence of different deformation curves on dynamic performance of the bridge under vehicle load was studied.