Entropy Application for Simulation the Ballast State as a Railway Element

The purpose of the paper is to develop methods of entropy application for simulation of the ballast layer operation of a railway track in the tasks of predicting and controlling the service life. The author developed a method for determining the entropy of the ballast layer as an element of a railway track through calculations of the mechanical work performed by ballast as a result of the reaction to an external load. To determine the array of stresses and deformations operating in the ballast layer space, the spatial model of the stress-strained state of a railway track based was used on the elastodynamic problem. The major part of the developed method is supplemented by the technique of assessing the entropy of a system according to the deviation measuring results in its geometric position. The geometric position of a railway track was measured by a track renewal train. Files archiving to determine the randomness of data recorded in them were carried out using the LZMA algorithm. The tasks of predicting and controlling the service life of ballast have been further developed. The usage of entropy has allowed simulating the ballast degradation as a random process that depends on cyclic stresses and deformations arising in ballast from rolling stock. For the first time, the method of assessing the quality of the track surfacing through the entropy of the ballast layer is proposed. The developed mathematical tool may be used to compare the service life of ballast in various operating conditions, which allows optimizing consistency between the track design and parameters of train movements.