Analysis And Evaluation Method Of Line Quality Based On Track Irregularity

The quality level of ballastless track of high-speed railway directly determines whether the high-speed train of CRH can run smoothly and safely.In recent years,the typical diseases of CRTS ? and CRTS ? track systems often occur,so the quality analysis and dynamic diagnosis of typical disease sections become particularly important.Field experience shows that the Slab-Warping and Mud Pumping are the main manifestations of the deterioration of track service performance,which lead to the change of track geometry,and then affect the stability and safety of train operation.In order to alleviate a series of line problems caused by these typical diseases,the maintenance departments spend a lot of manpower on the general survey of line diseases.Therefore,in order to prevent the serious problems caused by the typical diseases of ballastless track,it is particularly important to carry out the research on dynamic diagnosis method of track diseases.The research content of this paper is the track quality analysis and evaluation method based on the track smoothness,including the pretreatment method of track irregularity data,time-domain characteristics and power spectrum analysis,dynamic diagnosis method of CRTS ? track Slab-Warping section and dynamic diagnosis method of CRTS ? Mud Pumping section.(1)In the preprocessing stage of track dynamic irregularity,this paper analyzes and processes the quality problems of the measured data,and puts forward the relative mileage correction algorithm,which is improved and optimized based on the existing algorithm.The results show that the preprocessing method can accurately identify the repetitive value,missing value and abnormal value,and correct them.The relative mileage correction algorithm realizes the accurate correction of the whole line mileage.(2)In the phase of time-domain characteristics and power spectrum analysis of track irregularity data,this paper introduces the time-domain waveform characteristics of track irregularity,and analyzes them with the field case data.The results show that the degradation of track service performance can be found from the superposition of track irregularity historical data.The track irregularity spectrum can reveal the wavelength energy characteristics of the typical periodic irregularity.(3)In the stage of dynamic diagnosis method of CRTS ? track Slab-Warping section,this paper analyzes the time-frequency characteristics of vertical irregularity caused by CRTS ? track Slab-Warping diseases,extracts the vertical irregularity characteristic data of the Slab-Warping section based on discrete wavelet transform,and puts forward the SlabWarping index(SWI)for dynamic diagnosis of the Slab-Warping section.The results show that the vertical irregularity will show obvious periodic characteristics in the time domain and the wavelength characteristic energy of 6.45 M is prominent in the track irregularity spectrum when the CRTS ? ballastless track is damaged.The proposed Slab-Warping index SWI can realize the positioning and evaluation of the Slab-Warping section,and the effectiveness and accuracy of the proposed method are verified by typical cases.(4)In the stage of dynamic diagnosis method of CRTS ? Mud Pumping section,this paper analyzes the time-frequency characteristics of vertical irregularity caused by CRTS ? track subgrade Mud Pumping disease,extracts the characteristic data of irregularities wavelength that can reflect the Mud Pumping disease based on the multi-scale method,and proposes the Mud Pumping index(MPI)for dynamic diagnosis of Subgrade Mud Pumping section,and the three-level classification and management method of the Mud Pumping diseases are formulated.The results show that the vertical irregularity time-domain waveforms are concave when the CRTS ? track is damaged by Subgrade Mud Pumping,and the energy with the length of slab(4.95M)or multiple of slab length as the wavelength feature is prominent in the track irregularity spectrum.The MPI can realize the location and evaluation of the Mud Pumping disease,and the hierarchical management method has certain guiding significance for the field maintenance.