Structural Strength and Safety Secured, with Expanded Utilization Expected in the Second Half of 2025
The Korea Railroad Research Institute (KRRI), led by President Sagong Myung, is expected to contribute to resource circulation and carbon neutrality by developing a technology that can replace wooden railway sleepers, whose production is scheduled to be discontinued starting in 2026.
On the 13th, KRRI announced that it has commercialized its research成果 on the “Slastic Sleeper,” made from 100% recycled thermoplastic plastics and steelmaking byproducts, and has installed the sleepers at POSCO’s Pohang Steelworks (main lines and turnouts) and Gwangyang Steelworks (main lines).
The name “Slastic Sleeper” is derived from a combination of plastic and steelmaking slag, a byproduct of steel production. The main material consists of recycled thermoplastic plastics, while the reinforcement material uses industrial byproduct slag generated during POSCO’s steelmaking process.
By reapplying byproducts from POSCO to railway sleepers within steel plant railways, KRRI has realized a circular economy model. The completed sleepers are designed to be recyclable even at the end of their service life, enhancing environmental sustainability and resource circulation throughout the entire product life cycle.
The sections where the Slastic Sleepers have been installed include main lines and turnouts at the Pohang Steelworks, where Torpedo Ladle Cars (TLCs) transport molten iron. With molten iron temperatures exceeding 1,500°C and TLC weights reaching up to 650 tons per car (including molten iron), the sleepers were developed to ensure stable operation even under extreme high-temperature and heavy-load conditions.
