Influence of unsupported sleepers on flange climb derailment of two freight wagons

Abstract

Two freight platform wagons connected together conventionally or in the form of so-called rigid connection were taken into account to investigate the influence of unsupported sleepers on climb flange derailment on transition curve. Presented results are related to the freight wagons equipped with two-axle Y25 standard bogies, entering at an acceptable speed in the transition curve of the track with the radius of 150 or 1,000 m. Three cases have been analyzed: only the inner rail, only the outer rail, or both rails had unsupported sleepers. Simulation models were prepared using the VI-Rail software and nonlinear wheel–rail contact model. The dynamic calculations showed that wheel flange climb derailment caused by unsupported sleepers will only occur if deflection of the rail or track on transition curve is deep enough. These tests allowed us to determine the relationship between the radius of curvature and the depth of the trough causing derailment of the wagons. Calculation results allowed us to answer also the questions whether the method of connection and the weight of freight wagons have a significant impact on the wheel flange climb derailment.

Keywords

• transport safety
• transition curve
• unsupported sleepers
• wheel flange climb derailment