The layer of coarse, angular, and uniform-sized stones or gravel placed underneath the sleepers to provide stability, drainage, and load distribution for the track structure.

This refers to all ballast between two sleepers (in-center distance).

The height of the crib ballast layer.

The distance between two sleepers, usually measured between the centers of sleepers.

The edge of the topmost layer of the ballast formation.

The bottom edge of the ballast formation, just above the subgrade or slab structure.

The height at which the sleeper is embedded in the ballast layer.

300 to 450 mm on both ends of sleepers.

1:1.5 up to 1:2.

1/3 to 1/2 depth of sleeper.

At least 270 mm for wooden; at least 300 mm for concrete.

1.1 to 1.3.

The layer of soil or material that serves as the foundation for the railway track structure; located underneath the ballast layer and supports the entire track structure.

Additional or modified components of railway tracks placed in the track structure to address specific operational needs.

Supplementary components of rail fastening assemblies used to prevent the longitudinal movement of rails caused by rail creep or thermal expansion.

Components meant to guide train wheels through curves or complex track structures (such as turnouts) by providing controlled constraint on wheel movement; reduce derailment risk by maintaining alignment.

Structural blocks or walls designed to prevent train derailments from escalating into more severe accidents.

Safety devices installed on railway tracks that intentionally derail a train or rail vehicle in controlled situations to protect critical or restricted areas such as work zones.

A safety device found at the end of a railway track that prevents trains from going beyond the end of the line when braking systems fail.

Additional conductive rails running parallel to the main track that serve as the source of electric power for trains, mounted on insulators and contacted by collector shoes.

The track structure components vary depending on the type of track used; railway tracks come in different configurations chosen based on speed, traffic volume, geography, train type, and other operational requirements.

Track Design and Construction. The most common type of railway track structure, consisting of steel rails supported by sleepers resting on a ballast layer; widely used in traditional and heavy freight railways.

Track Design and Construction. A type of track where rails are mounted on a continuous concrete slab instead of ballast, minimizing maintenance and improving load distribution; used in high-speed and urban rail systems.

Ballastless Track. A common type of ballastless track where rails and fastenings are mounted directly on a continuous reinforced concrete slab, providing high stability and low maintenance; used in high-speed lines and tunnels.

Ballastless Track. Rails supported on individual or continuous elevated concrete plinths instead of a full slab; allows improved drainage and cable access, commonly used on viaducts and tunnels.

Ballastless Track. A ballastless track type using pre-cast concrete panels manufactured off-site, providing consistent quality and allowing faster construction.

Track Design and Construction. A type of track where rails (typically grooved rails) are embedded in concrete or asphalt, laid on vibration-damping materials; commonly used in city streets where rail systems share the roadway with vehicles.

Specialized tracks used in depot pits or inspection pits to allow maintenance crews easy access to the train underbody during inspections and repairs.

A mechanical installation that enables rail vehicles to be guided from one track to another; a key component of railway infrastructure allowing trains to move between different tracks.

Functions. The primary function of a turnout, enabling a train to switch between two different tracks in yards, depots, junctions, and stations.

Functions. Turnouts redirect trains from one track to another to help manage rail traffic without requiring trains to stop.

Functions. Allows a slower train to move onto a siding or parallel track so that a faster train may pass.

Functions. Turnouts enable trains to use alternate routes, improving flexibility during rerouting, disruptions, or track maintenance.

Functions. Properly designed and maintained turnouts ensure safe transitions between tracks, reducing derailment risks.

COMPONENTS. The section of the turnout responsible for directing the train to continue straight or switch tracks.

Point Part. A movable rail with a tapered, sharpened tip that pivots or slides to guide the train to another track.

Point Part. A baseplate that supports the tongue rail and allows its movement during switching.

Point Part. Plates used to secure the rails to sleepers in turnout areas, ensuring alignment and stability.

Point Part. Connecting rods that maintain gauge and ensure both tongue rails move simultaneously.

Point Part. A mechanism (manual or motorized) that controls the movement of the tongue rails.

Point Part. A block located at the heel end of the tongue rail to prevent excessive lateral movement and ensure correct alignment.

COMPONENTS. The intermediate track section connecting the tongue rail to the crossing area.

Lead Part. A straight or curved rail extending from the heel of the tongue rail toward the frog area.

Lead Part. The stationary main rails in the turnout that guide the tongue rails.

COMPONENTS. The section where two rails intersect, allowing vehicles to cross from one track to another.

Crossing Part. Part of the frog assembly that guides inner wheel flanges when switching tracks.

Crossing Part. The V-shaped part of the frog that separates the diverging tracks.

Crossing Part. A rail placed beside the main rail to guide the outer wheel flange and prevent derailment.

TYPES OF TRACK TURNOUTS. The basic turnout type allowing trains to switch to a single diverging path; commonly used in yards and junctions.

TYPES OF TRACK TURNOUTS. A turnout with equal divergence on both sides, enabling switching in either direction; used in double-track lines.

TYPES OF TRACK TURNOUTS. A turnout where the two diverging angles differ, used in areas with limited space.

TYPES OF TRACK TURNOUTS. A type of turnout where one nose rail runs continuously and the wheels run over it; used to divert trains to a safer track.

TYPES OF TRACK TURNOUTS. A track structure where two tracks intersect at an angle, forming a diamond shape; found in complex yards and stations.

TYPES OF TRACK TURNOUTS. A pair of turnouts that allow trains to move from one parallel track to another; common in stations and yards.

TYPES OF TRACK TURNOUTS. A combination of turnouts and crossings providing maximum routing options in high-traffic areas.

TYPES OF TRACK TURNOUTS. A turnout that allows diverging movement while also permitting straight movement through a diamond crossing.

TYPES OF TRACK TURNOUTS. A combination of two single slip switches, enabling switching in multiple directions through a diamond crossing.

A designation indicating the geometry and spread of rails at the frog; serves as a standard identifier for turnout geometry.