Research On Mechanical Properties Calculation And Test Of New-type Heavy Horizontal Rotating Bridge Bearing

At present,the bridge swivel construction method has been widely used in the construction of highway and railway in china,this method has the advantages of fast construction speed,high safety performance and little interference to the existing lines.As the key structure in the construction,the swivel bearing bears the important bearing and rotation function.Based on the bridge above of a railway,the paper has studied the stress of large tonnage swivel bearing when loading and swiveling.In this paper,the spherical hinge rotation method and the stress assessment method under spherical hinge has been introduced to analyze the unbalance moment,and the lifting force of the bearing end has been calculated by using the spherical hinge rotation method combined with the actual structure of the support.In view of the fact that the actual structure of the contact surface of the spherical hinge is not fully taken into consideration in the calculation of the rotational traction force in China,the stress at different radius position of contact surface of spherical hinge and the traction required for rotation have been calculated and compared by the simplified method,analytic method and the standard method.Combined with the analysis results,it is suggested that the simplified method can be used to calculate the tractive force in the project.Ansys15.0 was used to simulate the working condition of uniform load and eccentric load of the bearing in this paper,and the vertical displacement of the bearing,the vertical displacement and vertical stress of the wear-resisting plate,the Mises stress of the wear-resisting plate,the ball hinge and the embedded concrete were obtained.By comparing with the allowable value of the design,the safety of the swivel bearing under the design load was verified.In view of the stress excess of concrete embedded in some types of seat boards,the optimization suggestions of changing the thickness of steel plate and the outer diameter of support were put forward.The paper has proposed a design scheme for the model experiment of the swivel bearing and tested the swivel bearing that design bearing is 600 T.The results showed that the force of the bearing structure meets the requirements of the standard during loading compression and rotation testing,and the friction coefficient of the wear-resistant plate less than the design value.In order to understand the stress situation of the large tonnage swivel bearing,the vertical displacement of the concrete upper turntable,the stress under spherical hinge and stress of upper and lower seat plate of spherical hinge are measured when bearing is loaded.The unbalance moment and eccentricity of the bearing after the bearing was calculated by using the stress measured under the ball hinge,the bearing test results show that the stress values of the measuring point of the ball hinges are all satisfied with the design requirements,the stress on the epitaxial surface of the lower seat plate is larger than that of otherpositions,and this phenomenon accords with the engineering practice combining the actual structure of the bearing and the present situation of bearing.Stress monitoring is carried out under the spherical hinge of bearing and on the concrete turntable during the test run;stress monitoring is carried out under the spherical hinge of bearing,on the upper and lower seat plate and the concrete turntable in the rotation.The stress measurement value under the spherical hinge indicates that bearings are in balance before and after the trial turn and swivel,and the unbalanced moment and eccentricity of the bearing is existed after the test.Test and rotation process monitoring results show that the stress values of the measurement points on the ball hinge and turntable satisfy the design requirements,the structure is safe.