Assessment of mechanical properties of roller compacted concrete with reclaimed asphalt pavements

Reclaimed asphalt pavement (RAP) is a sustainable alternative to natural aggregates, addressing material shortages in construction and promoting eco-friendly practices. In this study, the effect of partial replacement of the RAP in roller compacted concrete (RCC) is investigated, whereas the mechanical properties of obtained concrete mixtures are quantified. The obtained RCC mixes are modified by partial replacement of 10% of cement with silica fume (SF) and an addition of 2% steel fiber (St.F) of the total mix as a reinforcement resulting in improvement of the mechanical properties of RCC. Replacement of natural aggregate (NA) by 100%, 70%, 50%, and 30% of RAP are tested for the altered RCC mix. A total of 129-cylinder RCC samples are prepared and evaluated for mechanical and physical properties for the obtained RCC mixes. The samples were evaluated for compressive strength, tensile splitting strength, the modulus of elasticity, the toughness, the water absorption, and the density. The results showed an increasing trend in compressive strength, and modulus of elasticity, and modulus of toughness with increasing RAP percentages. Contrarily, the RCC density and water absorption were reduced by increasing RAP percentage. While the tensile splitting test results did not show a clear trend by altering the RAP percentages. The obtained compressive strength (20.53 MPa) for 100% RAP is still a reasonable value for pavement with light traffic, sidewalks, or similar constructions using RCC mixes. The study showed that the RAP is recommended for potential utilization of numerous known waste materials in the RCC construction.