In the field of railway track construction, ballasted track and ballastless track are two mainstream forms. Due to their different structures, performances and costs, they are suitable for a variety of transportation scenarios.
Ballasted track is composed of rails and sleepers laid on gravel ballast with gravel ballast as the core. Gravel ballast can disperse train loads, drain water and reduce shock, has low requirements for foundations, is easy to construct and has controllable costs. In ordinary railways and mountain railways, ballasted tracks can effectively adapt to complex terrains, and slight deformations can be repaired by replacing ballast. However, the gravel ballast is easily affected by train vibrations and becomes loose and compacted, requiring regular tamping and cleaning maintenance. When the train is running at high speed, ballast splashing may threaten driving safety.
Ballastless track uses concrete ballast instead of gravel, and the rails are directly fixed to the reinforced concrete slab or the integrally cast ballast structure through fasteners. It has strong integrity and high stability, which can greatly reduce the vibration and noise of trains during operation, and is more suitable for high-speed lines such as high-speed railways. Taking high-speed railways as an example, ballastless tracks ensure that trains can run smoothly at speeds exceeding 300 kilometers per hour. In addition, ballastless tracks have a long maintenance cycle and a service life of more than 60 years. However, its construction cost is high, and the foundation settlement is strictly controlled. Once a disease occurs, the difficulty and cost of repair are much higher than that of ballasted tracks.
Choosing ballasted or ballastless tracks requires comprehensive consideration of factors such as the line design speed, terrain conditions, and maintenance budget. Ballasted tracks serve conventional transportation with their economy and adaptability, and ballastless tracks support high-speed transportation with high smoothness and durability. The two together build a modern railway transportation network.