The Rearch Of Ballastless Tracks' Diseases Detective Technology In High-speed Railway Based On The Ground Penetrating Radar

This paper focused on the ballastless tracks' diseases situation during the operation of high-speed railway.By studying the ballastless tracks' diseases mechanisms,established the diseases' model and forward modeling.Explored the feasibility of ballastless tracks' diseases' detection using ground penetrating radar(GPR).Designed the suitable detection scheme,classified the ballastless track disease based on radar image,and conducted the experimental feature extraction of ballastless track diseases with the application of support vector machine(SVM)theory,according to the measured radar data.(1)According to the various ballastless tracks' disease,on the premise of basic causes and performance characteristics of the disease,based on the abstract of the current classification method,classify the typical diseases according to the diseases'types,diseases' factors,diseases' performs and the diseases' prone positions.(2)With fully understand of the GPR electromagnetic wave propagation theory and connecting with the high speed railway ballastelss tracks' electromagnetic characteristics and GPR's working principle during the detection of subgrade,this paper discusses the GPR's applicability in the detection of ballastless tracks and designs the detection scheme of GPR.(3)Based on the finite difference time domain principle,establish the model of the ballastless track and its diaseases,forward modeling the normal bed and the typical diseases and study the ballaseless tracks' diseases' image features.Through the contrast analysis of the typical diseases forward modeling image and the real radar image,get the features of the diseases' radar image.Classify the ballastless tracks' diseases based on the GPR images features and then provide theoretical basis based on support vector machine(SVM)for feature extraction.