Müslüm Murat Maraş, E. Eki̇nci̇
Reinforced concrete sleepers are critical components in modern railway systems, especially on high-speed and heavy-load lines, as they ensure safe load transfer to the ground. However, conventional sleepers often face durability problems over time, which may lead to safety risks and economic losses. This study investigates the use of ultra-high-performance alkali-activated slag concrete (AASC) as an alternative material to address these limitations. In the first phase, fiber-free AASC mixtures with varying NaOH molarities and silica fume replacement ratios were produced to determine the optimal mix. In the second phase, the influence of fiber reinforcement on the compressive strength, flexural strength, and sulfate resistance of the optimized mixture was evaluated. Finally, the structural performance of non-prestressed RC sleepers and steel fiber-reinforced AASC sleepers was compared under loading. The findings reveal that AASC sleepers exhibit superior strength, ductility, and energy absorption capacity, indicating strong potential for use in advanced railway systems.