Stability Analysis Of No.12 Single Open Welded Turnout At Jade Everest Station Of Qinghai-tibet Railway

As the development of China's cross-section seamless lines is maturing,seamless turnouts are an important part of the realization of cross-section seamless lines.The research on its design,laying and maintenance and repair issues has become increasingly important.The analysis of the stability problem of seamless turnouts is also going deeper.At present,the Qinghai-Tibet Railway is being reconstructed from the interval seamless line to the cross-area seamless line.The work of replacing the seamless turnout is gradually completed.Based on the research background of the Yuzhufeng Station on the Qinghai-Tibet Line,this paper establishes a three-dimensional nonlinear finite element of seamless turnout The model analyzes the stress and deformation of seamless turnouts under the influence of temperature force,lateral irregularity of track and roadbed settlement.The main research contents are as follows;(1)In this paper,based on the spatial member system,the calculation program is compiled through MATLAB to establish a three-dimensional nonlinear finite element model of seamless turnouts,and the analysis of the change rule of the lateral displacement of the seamless turnouts and the causes of the peaks of the lateral displacements under different temperature rise conditions,and The unfavorable position points for the lateral deformation of the turnout are obtained at the tip of the sharp rail,the heel of the sharp rail,the middle of the guide curve,the end of the wing rail,and the straight side strand separation point.The analysis shows that the rigidity of the rail frame and the unit rods used as the force transmission medium,the connection form and line shape change,will have a great influence on the lateral deformation of the seamless turnout.(2)Through the calculation program,simulate the irregularity of the line,and analyze the lateral irregularity of the seamless turnout at each unfavorable position and the vertical irregularity of the track caused by the settlement of the subgrade.Under the action of temperature force,the lateral deformation of the turnout and the lateral The development law of displacement.Comparing various working conditions,the interaction effect of each track inside the turnout and the degree of influence of each unfavorable working condition on the lateral deformation of the seamless turnout are analyzed,and the change curve of the rail lateral displacement under each working condition is given.It can be concluded that when the lateral deviation of the curved rail of the guide curve part will cause a greater lateral deformation of the seamless turnout,and the increase of the lateral displacement of the outer straight base rail is more obvious.Under the condition of roadbed settlement,the curved part of the guide rail part and the straight part of the rail part of the turnout float up,which has a significant effect on the lateral deformation of the seamless turnout.(3)According to the most unfavorable position calculated by the model under the action of temperature force,and the deformation of the turnout calculated under various working conditions,combined with the actual measured data and the actual situation of the QinghaiTibet Railway,the corresponding maintenance suggestions and measures for seamless turnouts are given.