Experimental Analysis of the Use of Reclaimed Asphalt Pavement as Partial Replacement of Coarse Aggregate in Concrete for Rigid Pavements

Abstract

This study evaluates the feasibility of using reclaimed asphalt pavement (RAP) as a partial replacement of coarse aggregate in concrete for rigid pavements, designed with a characteristic compressive strength of f’c = 210 kg/cm2. Concrete mixtures incorporating RAP at replacement levels of 5%, 10%, and 15% were produced and compared with a conventional control mixture. Prior to mixing, natural aggregates and RAP were characterized through particle size distribution, moisture content, specific gravity, absorption, Los Angeles abrasion, and unit weight tests. The workability of fresh concrete was evaluated using the slump test. In the hardened state, compressive strength tests were performed on cylindrical specimens, while flexural strength (modulus of rupture) was determined using concrete beam specimens. The results indicated that the mixture containing 5% RAP exhibited the best mechanical performance, showing an approximate increase of 29% in compressive strength and 4% in flexural strength compared to the control mixture. In contrast, mixtures with 10% and 15% RAP showed a decreasing trend in mechanical properties. The findings demonstrate that the controlled use of RAP as a partial replacement of coarse aggregate is technically viable and contributes to environmental sustainability by reducing asphalt waste and the demand for natural aggregates. It is concluded that an optimal RAP content of 5% is suitable for application in concrete for rigid pavements, provided that proper material characterization and quality control are ensured.