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.

In this work, considering the MÁV’s (i.e., the Hungarian Railways) five small and five high-traffic railway lines, the statistical distribution and change of the track gauge parameter were analyzed, under a ten year, on time-series analysis, related to straight track sections. The analysed data, were bottom track gauge measurements, of the FMK-004 and FMK-007 type railway track geometry, measuring and recording car & wagon. Taking into account the railway tracks, the track gauge parameter cannot be controlled and improved upon by large machine methods, but its permitted value depends on the allowed speed (and vice versa). The main independent variables were the elapsed time and the through-rolled axle tons (as a function of time, i.e., the MGT). To generate the statistical analyses, Vaszary-like shape numbers were computed, considering the distribution functions of the measured data series of the track gauge parameter every 25 cm. The authors examined the change of the shape numbers, the average and standard deviation values of the track gauge, and the shape of the distribution functions (skewness and kurtosis properties). In the end, a spectrum analysis of the measured data series was produced. In conclusion, the Authors provide relevant statements regarding the track gauge parameter.