Estimation of the Horizontal Curvature of the Railway Track Axis with the Use of a Moving Chord Based on Geodetic Measurements

Abstract

The paper presents the application possibilities of the new method of determining the curvature of the axis of the railway track, called “the method of the moving chord.” Based on the estimation of the existing curvature, it becomes possible to identify the geometric layouts of the track in the horizontal plane. As shown in previous publications, for model layouts, the method of the moving chord shows full compliance of the obtained curvature diagrams constituting the basis for obtaining the corresponding geometric solution. Now, the question of its use for the estimation of the horizontal curvature of the axis of the operated railway track, based on Cartesian coordinates obtained by direct measurements, has been taken up. Measurement data from two geometric layouts of the track with clearly different values of the radius of the horizontal arc and the nature of the curvature present were used. In both cases, the obtained curvature diagrams are less regular and oscillatory in nature, which does not prevent the basic geometrical parameters of the measured layout from being estimated on their basis. The presented adaptation of the moving chord method to the adopted measurement procedure and the practical use of the obtained curvature diagram provide the method in question with appropriate implementation bases. The application of the presented procedure should significantly improve the process of identifying geometric track layouts.