Research On The Track Irregularity And Treatment Of Subgrade-bridge Transition Section For Han-yi Railway

Han-yi railway went into service on july 1,2012,with ballasted track along the whole line.For eight years,Han-yi railway had been running CRH and direct trains only,operating speed of 200 km/h in the near future,long-term retention ability to running 200 km/h with mixed passengers and freight.After operating for some time,the long wave diseases and excessive TQI begin to emerge,the irregularity for transition section,especially the subgrade-bridge transition section has plagued the maintenance department.For the irregularity of Han-yi railway subgrade-bridge transition section,first study the causes of irregularity in this article,mainly because of the rail surface deformation caused by differential settlement and stiffness of subgrade-bridge.The track dynamic geometric dimensions and TQI is the most direct quantization for the rail surface deformation.Using Intelligent Software of Track Dynamic Analysis,all of the112 subgrade-bridge transition sections were tested for nearly three years by the dynamic inspection car to get a comparative analysis of the track dynamic geometric dimensions and TQI,then summing up the deterioration law of track geometry and TQI in different seasons and in multiple tamping cycles to guide the maintenance department and big machine stamping practice.Further study the track geometry and TQI degradation mechanism under the action of the wheel-rail force on the subgrade-bridge transition section,and use the multi-body dynamics theory to establish a dynamic calculation model for the subgrade-bridge transition section with ballast on the subgrade and on the bridge with a speed of 200 kilometers per hour.Analyze the dynamic response in both cases: passing through transition section at the same speed with different prof amplitude and passing through the same transition section at different speeds.According to the analysis of the deterioration law for the track geometry and TQI,filter out the subgrade-bridge transition sections,which are still needed a maintenance and on a fast deterioration.To resolve the irregularity problems of these key transition sections,accurate tamping can greatly improve the irregularity of the transition sections,but it can’t last a long time.subgrade grouting and polyurethane solidified ballast bed can control the subgrade sinking and rail surface deformation,enhancing the subgrade and track stiffness at the same time,entirely resolving the irregularity problems.Practice has been proved that subgrade grouting and polyurethane solidified ballast bed,these two methods combining together,can friendly deal with the irregularity of transition sections.