Mechanical behavior of a fiber reinforced reclaimed asphalt pavement sand-cement blend

Reuse of reclaimed asphalt pavement, RAP, provides an option to face the obstacles of both an economic and environmental nature, reintegrating the material into the soil as an alternative way either to dispose of it, or to reduce other aggregates’ usage. However, total or partial substitution must be associated with an improvement technique to abide by norms and regulations requirements, such as cement stabilization and fiber reinforcement. The research presented in this paper aims to evaluate the effects of including 24-mm polypropylene randomly distributed fibers on a mixture of a cemented sandy soil with a substitution of 30% reclaimed asphalt pavement (RAP) in lieu of soil. The experimental program was developed to examine the mechanical behavior of the mixture, including unconfined compressive strength, flexural tensile strength, splitting tensile strength, pulse-velocity, durability, and monotonic and cyclic simple shear tests, over different mixture dosages containing 3%, 5%, 7% and 9% Portland cement, 0.5% fiber, over a compaction effort to achieve dry weights of 16.4 kN/m³, 17.2 kN/m³ and 18.0 kN/m³. The fiber reinforced mixtures were compared to literature results, utilizing the same materials. Results indicate improvement of strength and durability overall, and also a possible drawback concerning the material’s Q3 shear modulus.