Research On The Variation Characteristics Of The Track Dynamic Irregularity In Railway Line

Track Irregularity is the primary cause for producing vibration of locomotive and car and share force between wheel and rail, and the important embodiment in comprehensive performance and carrying capacity for track infrastructure. The bad track irregularity will seriously affect the safety of transportation, the travel comfort level, the equipment's service life and track maintenance expenditure. This paper has made a study of variation characteristics of the track dynamic irregularity at one point, using historical wave data from track geometry car, and built a model for describing the irregularity's evolution, according to the variation characteristics. This can provide technical support for establishing track state forecasting model and making an economical and reasonable track maintenance schedule.Usually there are several different types of data which can reflect the current track state. Among these data, the wave data from track geometry car can reflect the real track state more accurately. Due to the lack of tools for analyzing track state and storing data, there are about 99% of wave data discarded. On the bases of the research on inspect frequency, sampling frequency and wave data format, this paper has carried on a research on how to utilize the data warehouse and Oracle database to store these massive wave data. This can solve the storage and management of wave data from track geometry car and provide the wave data for the study on the variation characteristics of track irregularity state.For the investigation on change law of track state, investigators from foreign countries, always according to different variation characteristics, build track state forecasting model. Because of the myriads of changes on many influencing factors of track state, different point in a railway line has the distinct variation characteristics. For building the track state forecasting model, this paper has done research on the variation characteristics of the track dynamic irregularity at one point, using the wave data from track geometry car, in ChengKun line, JingHu Up Line and JingHu Down Line, belonging to KunMing Railway Bureau and JiNan Railway Bureau, and has found out that the evolution of track state has three main variation characteristics: periodic, exponential and multi-stage. This establishes the foundation for the research of the change law of track state.According to the variation characteristics of the track dynamic irregularity, this paper has established a multi-stage linear fitting model for describing the irregularity's evolution, and also has verified this model using the wave data in ChengKun line, JingHu Up Line and JingHu Down Line.