DEVELOPMENT OF A DYNAMIC TRACK MEASURING DEVICE FOR GAUGE AND TWIST TO REDUCE DERAILMENT ACCIDENTS

Jin Z., Zhang W., Yin Z., Zhang N., Geng X.

Guo J., Liu J., Tian X., Yang J., Zhang Y., Tao K.

Track Quality Index (TQI) is a crucial indicator for assessing the condition of rail and rapid transit tracks. With the rapid increase of railway mileage and the complexity of processing large volumes of track inspection data, traditional methods that rely on a single device to process track geometry inspection data and calculate TQI no longer meet the efficiency and accuracy requirements of modern railways. This paper aims to propose a parallel method for assessing TQI track maintenance. The method is based on a multi-node data platform, using parallel computing technology to distribute different tasks in TQI calculation process such as track inspection data mileage correction, invalid data identification, and standard deviation calculation to multiple nodes. This approach enables standardized and rapid processing of large-scale track geometry inspection data. Using track geometry inspection data from various lengths of high-speed railway lines in China to test the proposed method, the results show that the new method significantly improves computational efficiency compared to traditional methods while maintaining high accuracy. The application of this method will greatly enhance the efficiency and accuracy of railway maintenance, providing robust technical support for the management and maintenance of railway infrastructure.

Wu Z., Lei F., Wang L., Fu Y.

Abstract To meet the demand for the track's geometric parameter detection equipment for train speed and high-speed aerodynamics tests, a zero-calibration gauge device is designed with the centering limit, height adjustment and horizontal display function in this paper. The bending situation of the zero-calibration gauge is analyzed and the processing technology is studied, which ensures the rationality and realizability of the design of zero-calibration gauge. Then the gauge zero value and the parallelism of the working surface of zero-calibration gauge have been experimentally tested. The experimental results show that the parameter of gauge zero value is 1434.829 mm with a standard deviation of 1.4 μm. The parallelism of the two upper working surfaces is 1.1 μm, and the parallelism of the two inner working surfaces is 4 μm. Finally, the uncertainty evaluation of zero-calibration gauge is completed. The measurement uncertainty of gauge zero value is 12 μm and the measurement uncertainty of height difference is 6 μm.

Bocz P., Liegner N., Vinkó Á., Fischer S.

On behalf of MÁV Hungarian State Railways Ltd., the authors carried out a research and development (R&D) project on behalf of the Budapest University of Technology and Economics, Department of Highway and Railway Engineering, on the subject of “Research and investigation of the causes of gauge narrowing by finite-element modeling in running track and turnout, and under operational and laboratory conditions”. The main objective of the research was to investigate the causes of localized defects of gauge narrowing in railway tracks based on machine and manual track measurements, laboratory measurements, and theoretical considerations. The measures proposed as a consequence of identifying the causes could significantly contribute to reducing the number and extent of local defects in the future. Furthermore, the research aims to develop new theories in less scientifically mature areas and provide procedures and instructions that professional engineers and practitioners can easily apply. The main areas of research, which are not exhaustive, are as follows: (i) the evaluation of the measurement results provided by track geometry measuring and recording cars; (ii) on-site investigations in the railway track in terms of gauge and rail profile measurements; and, based on these, (iii) the selection of concrete sleepers, which were removed from the track and subjected to more detailed geometrical investigations in the laboratory, together with the components of the rail reinforcement; (iv) the track–vehicle connection, tight running in straight and curved track sections under track confinement; (v) modeling of the stability and deflection of the rail when the rail fastenings lose part of their supporting function; and (vi) finite element modeling of the concrete sleepers under operating conditions such as slow deformation of the concrete, temperature variation effects, and lateral support on the ballast. In the already-narrowed track section, the tight vehicle running is not the cause of the track gauge narrowing but a consequence, so it is not investigated in this paper.

Fischer S., Németh D., Horváth H.

In this paper, the authors examined the change in track gauges in curves for several railway lines with low and high traffic in Hungary (i.e., secondary lines and main lines). They covered the processing of raw data as well as statistical calculations. The considered curved sections were transition curves (TCs) and circular curves (CCs), as well as—in some cases—entire curves (ECs), including TCs and CCs, but not dividing them into parts. The change of track gauge parameter as a function of elapsed time was analyzed based on the distribution functions by calculating the Vaszary-type shape number. A statistical test with the Kolmogorov–Smirnov test was performed, in which the question as to whether the measurement data of the railway lines followed a normal or lognormal distribution was examined; additionally, the skewness and kurtosis parameters were calculated and analyzed. The authors also took into account the impact of the track system and the sleepers. For the selected curves, the authors observed how the average track gauge changes and categorized them according to tolerances. In presenting and summarizing the tests, the authors formulated a conclusion for each study fulfilled. Despite higher traffic loads, the value of track degradation over time is lower for mainline curves than for secondary line curves. It is because the main line has stricter tolerances due to the higher speeds allowed, and more maintenance work is carried out on these lines. The authors concluded that the type of the track system and the sleeper type also influence the change in track gauges in curves. The accurate deterioration ratios for all analyses are contained in the paper.