Ballast track refers to the track structure in which the monolithic foundation such as concrete and asphalt mixture is used to replace the granular gravel track bed. It is an advanced track technology in the world. Compared with ballasted track, ballastless track avoids splashing ballast, has good smoothness, good stability, long service life, good durability, less maintenance work, and the train speed can reach more than 350 km per hour. Due to the characteristics of thermal expansion and cold contraction of concrete, the expansion joints reserved during ballastless track construction need to be sealed and waterproof with joint filling materials. Baiyun chemical can provide professional silicone caulking material solutions, which can perfectly solve the common problems of aging and cracking of caulking materials, insufficient expansion and poor adhesion with track bed in domestic ballastless track projects, and effectively improve the quality of track projects.