Gongquan Tao

• Southwest Jiaotong University

Accurate monitoring of track irregularities is very helpful to improving the vehicle operation quality and to formulating appropriate track maintenance strategies. Existing methods have the problem that they rely on complex signal processing algorithms and lack multi-source data analysis. Driven by multi-source measurement data, including the axle...

Wheel polygonal wear, especially high-order polygonal wear, has emerged as a significant challenge for Chinese railways over the past decade. The wheels of high-speed trains, locomotives and metro trains suffered from polygonal wear. Wheel out-of-roughness (OOR) of more than 43,000 wheels was collected in this study, including 30,500 high-speed tra...

Rail weld irregularities (RWIs) significantly influence the dynamic wheel–rail interaction. Evaluating and controlling these irregularities is essential for ensuring operational safety. In this study, the characteristics of RWIs measured on more than ten metro lines were analyzed, and the power spectral density of the RWIs based on the measurement...

The theoretical study of the tread braking mechanism to suppress railway wheel out-of-roundness (OOR) is of great importance for optimizing the braking strategy and reducing maintenance costs. In this work, a two-dimensional fully coupled thermo-mechanical finite element model of tread braking is developed, which takes into account the real contact...

A finite element (FE) model of wheel‒rail frictional heating with moving heat source is proposed in this paper for estimating the wheel‒rail contact temperature distributions under repeated long-term operation. To calculate the temperature rise in wheel‒rail friction, this study compares the computational accuracy and efficiency of the temperature...

Periodic track irregularities (PTIs) are an important and sensitive source of vehicle vibration and have attracted considerable attention from railway researchers. However, previous studies have mainly focused on the irregularities themselves, with limited investigation of how the rail wear band (RWB) generated by PTIs excitation affects vehicle re...

Wheel polygons can significantly impair the operational quality, service life and ride comfort of railway systems and even threaten the safety of train operations. Timely detection of wheel polygons is of great benefit in formulating a reasonable wheel maintenance strategy. First, to investigate the vibration response of the locomotive under wheel...

Recovering missing data to improve data quality is of great importance for prognostics and health management (PHM) of structures and machinery. Existing missing data reconstruction methods are generally limited by strong assumptions such as signal sparsity, coupled with heavy computational burdens, making them poorly adaptable to PHM data. To obtai...

In this study, the problem of severe wheel flange wear and tread rolling contact fatigue (RCF) of metro wheels with two wheel profiles, i.e., the LM-30 profile and the DIN5573-30 profile, is investigated. The contact characteristics of the two profiles are compared to analyze the causes of abnormal wheel flange wear and tread RCF. Based on the two-...

Wheel acoustic roughness of one metro line in China shows that the wheel polygonal wear (WPW) on both sides of the wheelset is asymmetrical. The dominant harmonics of the left and right wheels are 12–13, but with large differences in acoustic roughness levels. To analyse the causes of the asymmetrical WPW (AWPW), an investigation of the acoustic ro...

Two of the Shanghai metro lines suffered from severe side wear on the high rail, not only in sharp curves but also in large curves, and the service life of some rails on sharp curves was reduced by approximately 50% compared with the last rail replacement. Features and evolution rules for the rail side wear and the wheel flange wear were determined...

Timely monitoring of wheel polygon is of great importance for the formulation of railway wheel maintenance strategies. In this study, a novel data-driven method for onboard and quantitative detection of wheel polygon is presented. First, the axle box acceleration (ABA) signal preprocessing method and stationarity test are introduced to select the r...

Short-pitch corrugation is a serious problem on resilient fastened railway track for many metro lines, causing severe noise and vibration that shortens the life of the vehicle and track components. To address this problem, the formation mechanism of this kind of corrugation is investigated in this study. The corrugation characteristics and natural...

To investigate the influence of the structural deformation of the wheelset and track on rail wear in the longitudinal and lateral directions, a rail wear prediction model is established that can calculate the three-dimensional distribution of rail wear. The difference between the multi-rigid-body dynamic model and the rigid-flexible coupled dynamic...

Wheel polygonal wear (WPW) on-board detection based on axle-box acceleration (ABA) is a critical instrument for railway wheel maintenance. However, early WPW on-board detection under typical disturbances such as rail defects is still difficult to achieve. To face this challenge, this study proposes a weighted angle-synchronous moving average (WASMA...

The invention relates to the technical field of rail corrugation detection, in particular to a convolution regression-based vehicle-mounted quantitative detection method for rail corrugation roughness, which comprises the following steps of: 1. preprocessing and standardizing data, namely uniformly standardizing an axle box acceleration ABA signal...

Wheel transverse wear, irregular wear along the circumference (out-of-roundness), and rolling contact fatigue (RCF) are inevitable problems in the railway industry. One effective countermeasure to solve these problems is to apply a tread abrasive block (tread trimmer) that has the function of cleaning and repairing the wheel treads. In this study,...

The invention relates to the technical field of mechanical structure health monitoring, in particular to a self-adaptive SHM data cleaning method based on local outlier factors, which comprises the following steps: 1. dividing SHM data of the mechanical structure to be analyzed into a series of segments by using an adaptive sliding window ASW techn...

A novel algorithm for quantitative detection of rail corrugation roughness levels based on the axle box acceleration (ABA) signal is proposed. A convolutional regression model, named RCNet, was designed to extract the ABA features and detect the wavelengths and roughness levels of rail corrugation quantitatively. Dynamics simulations and field expe...

Coil springs are widely used in the suspension systems of railway vehicles to bear loads and isolate vibrations. Many vehicles in one metro line in China have suffered from spring fractures that exhibit typical fatigue characteristics. In this study, experiments and numerical simulation were conducted to investigate the root cause of the coil sprin...

Urban rail transit usually contains many small radius curved tracks, and wheel flange wear is prominent, which greatly reduces the service life and increases the maintenance and replacement costs of wheelsets. Two metro lines in Shanghai of China had suffered from severe flange wear since 2017, and the flange wear rate increased gradually over the...

Rail side wear is typically encountered in metro lines (particularly on sharp curves). A reliable rail wear prediction model to evaluate the evolution of the rail profile should be developed. In this study, a rail wear prediction model for a metro line is established. The vehicle system dynamics model is implemented in the SIMPACK software, which c...

The invention relates to monitoring of rail transit wheel-track short wave irregularity, in particular to a convolutional neural network construction method for rail track corrugation identification, which comprises the method for collecting and processing specific vibration information of a rail transit carrier, frequency domain data in a frequenc...

The invention relates to monitoring of short-wave irregularity of a rail transit wheel track, in particular to a rail corrugation identification method, which comprises the steps of acquiring specific vibration information generated when a vehicle moves along a rail in real time through a vibration sensor arranged on the vehicle to obtain vibration...

The application provides a training method, a using method, computer equipment and a computer readable storage medium for intelligently identifying an AI model in a wheel out-of-round state, which are beneficial to improving the accuracy of prediction of the AI model aiming at vibration response. The training method comprises the following steps: o...

The application provides a training method, a using method, a computer device and a computer readable storage medium of a regression prediction AI model of a polygonal wear waveform of a wheel. The training method comprises the following steps: obtaining vibration detection data of a detected wheel in the running process; extracting data from the v...

Rail corrugation is a very common wear phenomenon occurring on rail surface, especially on sharp curves, and is one of the main excitation sources of noise and vibration during railway transportation. Timely monitoring of rail corrugation is of great benefit to make scheduled maintenance and save maintenance costs. This paper proposes a novel me...

Rail corrugation is a very common wear phenomenon occurring on rail surface, especially on sharp curves, and is one of the main excitation sources of noise and vibration during railway transportation. Timely monitoring of rail corrugation is of great benefit to make scheduled maintenance and save maintenance costs. This paper proposes a novel metho...

Identifying abnormal data to improve data quality is of great importance for machinery health monitoring (MHM). Existing abnormal data detection methods generally depend on appropriate parameter settings and prior knowledge of data distribution, which result in relatively low adaptability to MHM data. To obtain more reliable MHM results, this paper...

In a railway vehicle air brake system, a brake pipe is used to connect all related elements, for example, the air source system, brake control device, and brake valve. The brake pipe has a significant impact on the safety and reliability of trains. This paper presents a fracture analysis of a brake pipe installed on the bogie of a metro train runni...

Severe high-order polygonal wear has been found on metro train wheels of one metro line in China, which causes considerable vibration of vehicle components and disturbing interior noise. Field tests and numerical simulations were conducted to investigate the formation mechanism and key influencing factors of wheel high-order polygonisation. Wheel o...

High-order and low-order wheel out-of-roundness (OOR) often occur on metro train wheels, which can intensify the wheel–rail dynamic interaction. A vehicle–track rigid-flexible coupled dynamics model is built through combining the dynamics software SIMPACK with the finite element software ANSYS, which is validated by field vibration measurement resu...

A denosing method that combines morphology filtering with moving average smoothing was proposed to overcome the shortcoming of unsmoothness in morphology filter. In order to provide a reference for the selection of structure elements in subsequent vibration signal denoising, the performances of morphological filter with different structure elements...

Polygonisation is a common nonuniform wear phenomenon occurring in railway vehicle wheels and has a severe impact on the vehicle-track system, ride comfort, and lineside residents. This paper first summarizes periodic defects of the wheels, including wheel polygonisation and wheel corrugation, occurring in railways worldwide. Thereafter, the effect...

Metro trains often encounter the problem of wheel flange wear when they pass through sharp curves, especially for the poor wheel–rail profile matching or lack of lubrication, evidently increasing the maintenance and replacement costs for wheelsets and rails. Based on the field investigation and numerical simulation, the cause of severe flange wear...

High-order polygonal wear wheels have been detected on metro express train operating on one metro line in China, which cause fatigue failures of steel coil springs in the primary suspension. A series of tests and theory analysis were conducted to figure out the mechanism of wheel high-order polygonal wear. The wheel out-of-roundness (OOR) measureme...

Discrete irregularities are a common issue occurring on locomotive wheels. The wheel roughness measured in the field sites indicates that some wheels suffer from discrete wheel irregularities, such as wheel flats or local defect. Meanwhile, the wheels exhibit obvious polygonisation. A wheel wear model is present to study the influence of discrete w...

Wheel polygonisation is a wavy wear on wheel’s circumference, which aggravates the wheel-rail interaction and prematurely invalidates or damages the components of vehicle-track system. This paper presents an investigation into the formation mechanism of high-order polygonal wear of metro train wheels through field experiments and numerical simulati...

Wheel flange wear often occurs on metro trains when they negotiate sharp curves, especially for the poor matching of wheel and rail profiles or lack of lubrication, which evidently increases the maintenance and replacement costs of the wheelsets and rails. The reason for severe flange wear of the original wheel profile on one metro line in China is...

A wheel wear model that considers the effects of temperature during tread braking was established on the basis of Archard's wear model. In the model, the temperature field of wheel tread was calculated using a numerical algorithm based on finite element method. The influences of temperature on the size of contact patch, division of adhesion/slip zo...

We present a detailed investigation of the mechanism of metro wheel polygonal wear using on-site experiments and numerical simulation. More than 70% of metro wheels exhibit 6 th –8 th harmonic-order polygonal wear; the excitation frequency of the polygonal wear is located in the 50–70 Hz interval at an operating speed of 65–75 km/h. To determine th...

Affected by the traction/braking, creep control and wheel-rail interface environment, wheel wear of locomotives is more complicated than that of other rolling stock. A locomotive wheel wear simulation model is developed, which includes a 3D locomotive track coupling dynamics model, a rolling contact model for rail traction vehicles based on Kalker'...

The objective of this study is to develop a new online model for wheel wear that takes into account the track flexibility. The proposed model consists of two parts that interact with each other, namely, (a) a locomotive/track coupled dynamics model considering the track flexibility, which is validated by field measurement results, and (b) a model f...

This paper presents an investigation into the mechanism of polygonal wear of metro train wheels through experiments conducted at field sites. The experiments comprise dynamic behaviour test of vehicle and track system, the wheel transverse wear and polygonal wear measurements, rail corrugation and rail weld joint irregularities’ measurements. Moreo...

Experiments were conducted at field sites to investigate the mechanism of the polygonal wear of electric locomotive wheels. The polygonal wear rule of electric locomotive wheels was obtained. Moreover, two on-track tests have been carried out to investigate the vibration characteristics of the electric locomotive's key components. The measurement r...

This paper presents a detailed investigation of out-of-round electric locomotive wheels through extensive measurement conducted at field sites. More than 2000 wheels, of seven types of locomotives widely used in China, have been measured since April 2013. The measurement results indicate that two types of freight traffic locomotives suffer serious...

To investigate the dynamic performance of wheel profiles of LM, S1002 and DIN5573, mainly used in metro vehicles in China, matching with profile of 60 kg/m (CHN60) rail under different rail cant conditions, a metro vehicle dynamic model was built to analyze the effect of rail cant on hunting stability of the vehicle, curving performances, wheel wea...

Three non-elliptic contact models, namely Kik-Piotrowski method, STRIPES and ANALYN, are first compared to the Hertz theory and the CONTACT code in terms of the normal contact solution. Further, for the contact models except for CONTACT, the tangential contact solutions are calculated by a modified simplified theory of Kalker (FASTSIM) based on the...