Pressure profile definition over the metal orthotropic deck surface of the decking superstructure ballast pocket from the local load action
The article discusses the interaction issue between the track and the rolling stock to determine the forces working on the track during the passage of a rolling load, and their further distribution through the ballast bed. The study aims to determine the vertical pressure profile working on the orthotropic metal ballast bed slab of the railway superstructure. To determine the load share from the rolling stock transferred from the rails to the cross-sleepers, the rail is represented as a beam of infinite length with one or several concentrated forces. To determine the cross-sleeper stress-strain state, it is considered as a short beam on a cushion course. The article presents the substantiation of the flow mechanics formulas application possibility to the ballast bed. Based on the Boussinesq problem solution, calculation formulas are obtained for determining the pressure along with the ballast bed plate. The results obtained by the proposed method were compared with other authors' experimental data and the finite element modeling results in the Midas FEA software package. The analysis took into account the design features of the ballast bed plates and the track superstructure on the existing superstructures. A theoretical study of the influence of the sheet of the covering bending stiffness on the pressure profile northing is carried out. The proposed method is applicable for various superstructure and the ballast bed slab, and also takes into account the uneven pressure distribution on the inner and outer rails from the trainload, changes in eccentricity along the length of the structure, different thickness of the ballast bed under the cross-sleepers ends, as well as the effect of centrifugal force.