Prestressed concrete sleeper

Concrete sleepers are a basic element in railway lines, used to maintain the rail and distribute the load on the base layer. They are designed to transfer load from the rail to other parts of the structure and are placed along the railway lines. Concrete sleepers are suitable for railway lines due to their high strength and hardness, long life, and reduction of vibration and noise during train passage.

Different types of concrete sleepers are available based on their shape and dimensions, catering to the specific needs of railway lines and local conditions.

The use of concrete sleepers in railway lines dates back to the 19th century in England. Initially, wooden sleepers were the main element in railway construction, but with the advent of reinforced concrete technology, they were gradually replaced by concrete sleepers. Due to their superior mechanical properties and strength, concrete sleepers became widely used in railway construction. The advancement of reinforced concrete technology further improved the quality and performance of concrete sleepers, making them the primary element in railway construction worldwide.

Concrete sleepers offer numerous advantages in railway lines. Firstly, they have high strength, capable of bearing heavy loads, and show significant resistance to pressure and lateral forces. Their three-dimensional structure provides high stability against lateral forces. The use of prestressed strands inside concrete sleepers increases their resistance and extends their useful life. Due to their long-term stability, concrete sleepers remain in railway lines for years without needing replacement. Additionally, concrete sleepers are recyclable and can be reused after replacement.

The production method of prestressed concrete sleepers can be continuous or non-continuous. In the non-continuous method, the mold is prepared, and the prestressing strands are installed inside. Initial and final tensions are applied, followed by concrete casting and vibration. After curing, sleepers are removed from the mold, fitted with seats, and finally installed in railway lines.

In the continuous method, sleeper forms are placed along a joint, and the strand, along with other accessories, is installed. Tension is applied, concrete is poured and vibrated, and the sleepers are covered with tarpaulin fabric for curing. After curing, sleepers are cut and separated, seats are installed, and the sleepers are stored and transported to the railway construction site.