What is it about?

The normal rail alignment can be illustrated as a ‘V’, ‘U’, or ‘S’ shaped function. The geometry of the trough in frog area can be presented as a rectangular, single-slope, or double-slope model. The dimension of the wheel is taken into account for the trajectory analysis, while the vehicle running through the turnout.

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Why is it important?

The reduced diameter of a worn wheel after lathing, and the wear and grinding of a nose rail can be considered. The study shows that the combination of an S-shaped alignment and a double-slope trough model is suitable for the characterization of the turnout geometry in the frog area.


I expect that this article could motivate the relevant studies about the rail geometric functions relative to the vehicle dynamics.

Ship-Bin Chiou
Taipei Rapid Transit Corporation

Read the Original

This page is a summary of: Modeling of railway turnout geometry in the frog area with the vehicle wheel trajectory, Proceedings of the Institution of Mechanical Engineers Part F Journal of Rail and Rapid Transit, November 2017, SAGE Publications,
DOI: 10.1177/0954409717739734.
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