Do you know what a track is made of

The components of a track include the ballast, sleepers, rails, connecting parts, anti-climbing devices, and turnouts. Initially, rails were mostly made of cast iron, and then gradually evolved into I-shaped rails. In the 1980s, the standard track gauge commonly used by most railways around the world was 1435 mm. Narrower than this standard is called a narrow gauge railway, while wider than this standard is called a broad gauge railway.

The ballast is laid directly on the roadbed, and the materials commonly used include gravel, pebbles, and slag. Rails, sleepers, and ballast, these materials with different mechanical properties, together form the track through a specific combination. Among them, the ballast is located at the bottom of the track. It not only provides the necessary elasticity for the track, but also has a drainage function. In addition, rails can also be laid on a concrete base, or more commonly on bridges, or even embedded in concrete.

Sleepers, usually made of wood, reinforced concrete or steel, are laid horizontally in the ballast. The rails are closely connected to the sleepers through connecting parts.

Ballast is the material laid on the roadbed and under the sleepers to support and protect the sleepers. Ballast is usually divided into two layers: the top ballast and the bottom ballast. Its function is to disperse the loads on the rails and sleepers, while maintaining the stability of the track and reducing vibration.

The primary function of ballast is to withstand the pressure transmitted by the sleepers and distribute this pressure evenly on the roadbed through its unique structure. Ballast also fixes the position of the sleepers, ensuring that the track can maintain its correct alignment and slope.

It also has a drainage function, which can remove rainwater around and under the sleepers, thereby preventing the soil in the roadbed from deforming due to wetness. The presence of ballast increases the elasticity of the track, allowing the rails to quickly return to their original correct position after the train runs over them. In addition, ballast can effectively prevent weeds from growing on the track.