Abstract
This paper presents research on the potential use of modified fiber-reinforced concrete for reinforced concrete sleepers, intending to increase their strength characteristics, crack resistance, and service life. To investigate the influence of reinforcing elements on the crack resistance of heavy concrete, chopped basalt fiber and, for comparison, polypropylene fiber were added to the concrete mix, both of which have shown promising performance. The results of the study showed that the modified heavy concrete exhibited improved crack resistance due to the formation of additional low-basic calcium hydrosilicates, compaction, and strengthening of the cement matrix, as well as the contribution of fibers to the formation of a spatially reinforced cement stone structure. The nature of the fracture of prism samples made from modified concrete and their crack resistance characteristics were evaluated. The results showed that samples with basalt fiber had a 40.59% increase in maximum load, a 40.5% increase in the conditional stress intensity factor, and a 40.49% increase in bending stress compared to the reference samples without fiber. In addition, the samples with basalt fiber demonstrated increases of 7.1%, 6.93%, and 6.9% in maximum load, bending stress, and stress intensity factor, respectively, compared to samples containing polypropylene fiber.