High performance concrete requirements for prefabricated high speed railway sleepers

Modern high-speed railway tracks require the use of prefabricated high performance concrete sleepers. Compared to wood sleepers, high performance concrete sleepers with their higher density and weight, provide the required stability to railway tracks for high-speed travel. Higher durability of concrete compared to wood also provides an important basis for the preference of concrete as the construction material for railway track sleepers. This paper, through a case study of sleeper production for a high-speed railway project, presents the strength and performance requirements and addresses unique production aspects of prestressed concrete sleepers designed with high strength concrete produced by the carousel method. This paper also highlights the importance of concrete tensile strength in sleeper design and prevention of aggregate segregation during sleeper production and the important provisions for the attainment of early concrete strength within carefully monitored curing conditions to prevent delayed ettringite formation.