Research On Track Geometry Parameter Optimization Based On Rail Wear Reduction Strategy Of Heavy Haul Railway

With the increase of the axle load of heavy-duty railway locomotive and vehicle,the wheel-rail contact stress increases during the train operation,and the rail wear problem becomes more serious,especially the rail side wear outside the curve section with small radius,which seriously reduces the service life of the rail.The essence of wheel-rail contact stress change is the change of wheel-rail contact relationship,and rail geometric parameters and wheel-rail contact relationship have a direct connection,so it is of great significance to study the influence law of track geometric parameters change on rail wear and the corresponding wear reduction measures to extend the service life of rail and improve economic benefits.For this reason,the following work is done in the paper.Based on the track-vehicle coupling dynamics theory,a rail wear prediction model was established based on the Archard wear calculation model and the multi-point contact KP algorithm.Taking the metal loss rate as the index,the influences of single track geometric parameters and the combination of multiple track geometric parameters on the rail wear in and out of the curve section were studied.The results show that the curve radius is the most important factor affecting the rail metal loss rate,followed by the gauge,rail bottom slope,ultra-high and line slope.According to the multiple track geometry parameters on the influence law of inner and outer rail abrasion curve is determined under 600 m and 800 m radius of four kinds of typical working condition,the track geometry parameters are determined by the simulation time to adjust the node and has a better local measures,through the rail of the whole life cycle simulation analysis contrast,has been further typical working conditions,the optimal scheme of track geometry parameters adjustment.The results show that the optimal track geometric parameter adjustment measures can effectively reduce the side wear of the curved track.The influence of track geometric parameter adjustment measures on rail life,the effective time and effective range of measures,and the influence of measures before and after intervention on train dynamic performance and safety performance are studied under typical working conditions.Based on this,the optimization scheme of track geometric parameter adjustment is evaluated.When the initial working condition is better,the earlier the intervention time is,the longer the effective time is and the less obvious the effect is;the later the intervention time is,the shorter the effective time is.When the initial working condition is ordinary,the earlier the intervention time is,the more favorable the intervention time is.When the radius of the curve is 600 m and the initial condition is optimal,intervening the optimal measure once in the middle of the curve has almost no effect on the rail life extension,while intervening the optimal measure once in the middle of the curve can prolong the rail life by 27%.When the curve radius is 800 m,the optimal measure of only intervening once in the midway has the same effect as the measure of initial intervening once and intervening again in the midway.In addition,WQI index is proposed to evaluate the optimization effect of the intervention measures based on the effective time of the intervention measures,the variation of the average metal loss rate and the extended rail life.