Guide bar

The rubber-tyred metro systems that incorporate 1,435 mm (4 ft 8 ¹⁄₂ in) standard gauge track have angle irons as guide bars, or guiding bars, outside of the two roll ways. The Busan Subway Line 4, that lacks a rail track, has I-beams installed as guide bars. The flanges are vertical. The Sapporo Municipal Subway, that lacks a rail track as well, has no guide bars. It has a central guide rail instead.

Ouchy M2 station, Showing the angle iron guide bars and the I-beam roll ways

View of a track from a sandpile bumper post, in the Montreal Metro near the Beaugrand Station, showing the unusual inverted U cross-section of the guide bars, precast concrete roll ways and conventional track