High speed turnouts’ geometry

Abstract

[Abstract:] Turnouts are singular points of the railway track. A series of advances have been added to their design in the last 20 years, in the same way as the other elements that constitute the track structure. These developments have allowed the vehicles to increase their running speed over the turnouts, as well as to improve their reliability and security, reducing, in this way, maintenance costs. This paper is focused in geometric improvements adopted in turnouts in order to get high speeds over direct (350 km/h) and diverging (160 – 220 km/h) tracks. These improvements are related to diverging track alignments introducing transition curves, switch rail design and mechanization in order to avoid the straight switch rail strike phenomenon, as well as to crossing modifications so as to avoid the existence of the gap.