Ensuring transportation under turnout switches loads exceeding design and regulatory criteria

Introduction. The need to rapidly increase the volume of railway transport is ensured by the use of heavy-load trains of increased weight and higher carriage axle loads. The capacity of the railway infrastructure does not always allow for unlimited use of such traffic organisation. Replacement of the existing track structures with modern ones designed for operation under heavy-load trains requires considerable time and material costs. During this time transportation has to continue on existing track structures, including the R50 light rail tracks. This research examines the capacity of switch economy in terms of safe movement of heavy-load trains on operated turnout switches before they are replaced by special ones designed for heavy-load traffic.Materials and methods. The paper is based on the results of research of stress-deformation state of the main elements of turnout switches affected by rolling stock with different axle loads. It also uses the results of analysis of resource indicators of turnouts under different operating conditions on the road network. The analysis of the influence of rolling stock axle loads on the service life indicators of turnout switches elements applied the methods of mathematical statistics and reliability theory.Results. The authors obtained predictive data on the service life trends, failure-free operation likelihood and failure rate of the main elements of turnout switches with an increase in the loads of rolling stock circulating on the turnout switches up to 25 t/axle. The researchers developed a method of predictive analysis of turnout switches service life indicators.Discussion and conclusion. The predictive analysis is versatile and could be used for assessing the influence of rolling stock axle loads on service life indicators of track structure elements. The authors developed proposals to ensure traffic safety under heavy-load train traffic on the operated turnout switches. These conclusions are useful in organising the current maintenance of turnout switches on sections with heavy-load trains to be put into circulation.