The Time-frequency Analysis Of Track Irregularity And A Conjoint Analysis Of The Railway Train Vibration Response

Abstract:The deep research of the track irregularity is an issue of great importance to the scientific assessment, monitoring and management of track structure state. This paper has mainly done the following work after a carefully collecting and analyzing the track inspection data of high-speed railway (Beijing-Shanghai, Shanghai-Nanjing, and Shanghai-Hangzhou railway) and heavy haul railway (Shenchi-Huanghuagang heavy haul railway) and technical literatures:(1) Having a preliminary analysis on track irregularity spectrum’s characteristics and track spectrum fitting models of our nation’s typical heavy haul railway and high-speed railways.(2) This text put forward a detrimental wavelength analysis method based on mutual information (MI) theory and EEMD-cross Wigner-Ville Distribution, this method could not only reflect the detrimental wavelength or waveband which got from the coherence function, but also could well represent the distribute information of the detrimental wave-length (-band) in time domain.(3) This paper proposed automatic extraction algorithm of track irregularity characteristic (detrimental) wavelengths:at first, acquiring adaptively the track irregularity and car-body vibration signals at each frequency band through DWT (discrete wavelet transform) method, and then analyzing the (cross) Wigner-Ville time-frequency energies for the signals, using the HT (Hough Transform) farther suppress the cross distracters and the formula for extracting track irregularity characteristic (detrimental) wavelengths was derived lastly.(4) Based on the continue wavelet transform’s detailed performance in time-scale mesh generation, and combined with the probability method, the time, scale and time-scale wavelet energy spectrum of train vibration response and track irregularity signal was established after the calculating and analyzing of track irregularity and train vibration energy, then the combined diagnosis and analysis was conducted. The results show that the method this paper proposed can effectively extract the type, damage degree and space position of small disease, and realize the evaluation of track irregularity’s overall state.(5) In the study, the wavelet packet frequency band decomposition technology, coherent theory and energy analysis method were used, and proposed a comprehensive energy analysis method to calculate the carbody vibration considering the contribution of multi-type track irregularities. A formula to evaluate the energy of carbody vibration was presented.(6) This paper constructed a PCA-SVM integrated classifier, if combining with other track irregularity predicting method, the prediction of carbody vibration state of different evaluation index under a speed range can be realized after inputting the track irregularity signal.(7) This paper built the vehicle-track spatial dynamic programe, and analyzed the adaptability of time-frequency analysis method in dynamical simulation process.