The trackwork in the Metro tunnels comprises the elastic support track, fastened on concrete track-bed (Fixed trackwork).
The tracks have a standard gauge of 1435mm, made by UIC 54 rails, fastened on bi-block sleepers – with microcellular footing and rubber boots – semi-embedded into the trackbed concrete. In addition, the third rail along with its protective cover is fastened on the sleepers, by means insulated brackets. Underneath the trackbed concrete there is a mesh for the collection of stray currents, embedded into the concrete of the tunnel invert. Concrete cable ducts are constructed at both sides of the tunnel; these ducts and their precast covers form the tunnel’s walkway.
The turnouts / crossovers are now installed using the direct fixation system on the concrete slab. Moreover, wherever necessary, measures for noise and vibration mitigation are implemented. In these areas, the turnouts / crossovers and the plain track sections are placed on floating slabs.
In the open-air areas of the Depots, the turnouts / crossovers are installed on wooden or concrete sleepers on ballasted track.