Universal method of track structure elements’ bearing capacity assessment on the basis of beam on elastic foundation simulation model

Abstract

Objective: To develop a universal method of track structure elements’ strength analysis, taking into account variable cross-section of elements and the form of foundation. To provide a graph-analytical model of analysis, as the basis of the method, for calculating stress-strain state characteristics of a beam on elastic foundation. Methods: Graph-analytical method was used to identify the characteristics of stress-strain state of a beam on elastic foundation. The method in question is an alternative one, compared to a routine theoretical calculation, the basis of which is a fundamental equation of a bending line and further from this equation, by means of successive integration method, any characteristic of stress-strain state of a beam on elastic foundation can be obtained. Results: A universal graph-analytical method was developed, taking into account factors, which cause deviation from a theoretical scheme of a beam bearing on elastic foundation, such as the possibility of calculating different elements of track structure bearing capacity, considering its variable cross-section (sole chairs, ferroconcrete sleepers, tongues, frogs, etc.), foundation form alternation, on which the calculated elements bear, as well as unequal elasticity of foundation. Practical importance: Application of such a universal method, which differs from an accepted idealized scheme of a beam bearing on elastic foundation, offers wide perspectives in stress-strain state assessment of not only new tracks, being designed, but also in the process of their current state. Application of the method in question makes it possible to avoid analytical lengthy mathematical calculations with any form of cross-section alternation along the length of a beam, with any form of foundation, as well as heavy expenditures, compared to other modern bearing capacity calculating methods, such as finite element method, finite difference method, and finite volume method.