Mechanical Response And Control Analysis Of Swivel Construction Of Long-span Continuous Beam Bridge

At present,with the rapid development of China's high-speed railways and the increase of transportation lines,the bridge's rotating construction technology is gradually being applied to the crossing line projects.Bridge rotating construction technology has excellent functions in crossing rivers and rivers and canyons.Vertical rotation,flat rotation and vertical and horizontal combination are common three construction methods,and the application of flat rotation is wider.Construction monitoring and stability control are the key technologies for turning construction.With the development of flat turn construction in the direction of large spans and large tonnages,coupled with the complexity of the structure,it is necessary to further analyze the construction of the bridges.In this paper,on the basis of referring to the relevant literature on the construction phase of rotation,combined with the Tongliao Railway Bridge as the subject background,based on the theory of finite element method,through the numerical simulation method and the theoretical calculation method,the continuous bridge construction will be carried out.Research,the main research content is as follows:(1)Simulate and analyze the construction process of continuous beam bridges to study the stress and deformation of the main beam under different construction stages.(2)Weigh the weight test and control the process of construction.(3)Analysis of the structural stability during the construction of the swivel.Through the method of numerical simulation,using Midas civil software to analyze the construction process of the bridge,it is found that the main beam is under pressure during construction,meets the requirements of the code,and the structure is safe.The deflection of the control section is compared with the measured value,and the error is within the specification requirements.The calculation of the pre-camber value is performed by the positive-fitting calculation method,and the construction is guided by the corrected elevation of the vertical model,which ensures that the actual line shape agrees with the design value.The asymmetrical moment of the structure was studied by the spherical hinge stress method,and the data of the weighing experiment was obtained.Mainly include:friction torque,asymmetrical torque and frictional resistance coefficient.The unbalanced moments are used to balance the weight,and the results of steering traction calculation are used to guide the construction control.The support system and anti-overrunning facilities are used to complete the precise positioning.Combined with the specification,the stability of the structure under wind load is demonstrated through theoretical calculations,and the stability is demonstrated to meet the requirements.The analytical solution to the angular acceleration is 4.9×10-3 rad/s2.By means of numerical simulation method,using ANSYS software to analyze the structure of the flat rotation force characteristics,the analysis shows that:the square of the stress and speed is generally positively correlated,and the stress and angular acceleration are proportional to each other.The speed and angular acceleration have a great influence on the stability.In acceleration rotation,the longitudinal bridge is pulled to the side of the axis,and the side is under pressure and the structure is safe,which verifies the rationality of the analytical solution.The rotational speed and angular acceleration were set to 0.017rad/min and 4.9×10-3rad/s2,respectively,and the upper limit value was used to guide the construction of the swivel to ensure the smooth turning of the bridge.