Analysis Of The Influence Of Track Irregularity On The Stability Of CWR

Jointless track has become an inevitable requirement for the development of track structure because of its stable driving and small maintenance work.However,large temperature forces accumulate in the long rail of the jointless rail,and there is a danger of expanding track runway in the initial irregularity section of the curve or track.At present,in the study of the stability of jointless track,the research on the development law of track irregularity under the action of temperature force is not deep enough.Therefore,the three-dimensional frame model of ballastless track jointless track is constructed in this paper,and the numerical calculation of the relationship between the stability of jointless track and track irregularity is completed by using the nonlinear finite element principle.The main tasks are as follows:(1)Construct an integrated three-dimensional spatial track frame model of seamless track.A nonlinear beam element with twelve degrees of freedom is used to represent the rail,and a two-node spring element is used to simulate the fastener connecting the rail with the sleeper.The sleeper is regarded as the linear beam element supported on the elastic foundation,the element stiffness matrix is consistent with the ordinary beam element linear stiffness matrix,and the longitudinal,transverse,vertical and torsional resistance of the track bed is replaced by the boundary constraint spring.(2)Analysis of the influence of orbit irregularity on stabilityThe finite element program for the stability of CWR is compiled to analyze the transverse displacement of CWR under different rails and rails.In this paper,the irregularities under different conditions of track transverse irregularity,vertical irregularity and composite irregularity are simulated,and the effects of temperature force on the deformation of CWR under different track geometric irregularities are analyzed,and the transverse displacement curves of rail under different conditions are given.It can be found that the track irregularity has a significant impact on the deformation of CWR when there are outward migration of doubletrack double-section four-node in lateral irregularity,upward floating of double-track doublesection four-node in vertical irregularity and outward migration and upward floating of doubletrack double-section in compound irregularity.(3)Analysis of the influence of track attachment strengthening equipment on stabilityOn the basis of the original track model,the ground anchor tie rod,which is used to strengthen the track,is applied to analyze the contribution of the ground anchor pull rod of different density to the jointless track,and to the track irregularity condition.The effect of anchor tie bar on the stability of jointless track is analyzed.The effect of anchor rod is more obvious when the vertical unevenness of subgrade is caused by the floating of roadbed.