Evaluación de la resistencia bajo carga monotónica de una mezcla asfáltica mdc-25 reemplazando parte de la fracción gruesa del agregado por concreto reciclado y estabilizado con cal

Abstract

Over time, the feasibility of using materials other than stone quarry aggregates to produce asphalt mixtures (construction of roads in flexible pavements) has been studied, within which concrete recycling has been identified as a possible material whose boom has occurred recently. This material has both good and bad characteristics for use as aggregate in mixtures. The most relevant negative factors are the high porosity of the Recycled Concrete Aggregate (RCA) particles, which 11 generate a higher consumption of asphalt and a lower resistance to wear and tear by abrasion and fracture, mainly due to the mortar adhered to these particles. In addition to the above, a stabilizing material was used in this study, in this case hydrated lime (making lime slurries made up of two doses lime: water 1:1 and 1:2), to cover the surface voids of the particles and mortar adhered to the RCA. In this research, the functional behavior of RCA stabilized with lime was observed when it is used as a substitute for naturally occurring coarse aggregate within a dense hot mix asphalt MDC-25 (INVIAS, 2013, article 450). This granulometry was chosen because it is the most used for building asphalt base layers in flexible pavements. Additionally, this mix allows the substitution of larger stone aggregates compared to mixtures of the MDC-19 and MDC-10 type. This functional behavior analysis was carried out through two basic tests: Marshall (INV. E-748-13) and indirect traction (INV. E-725-13). The results obtained from the MDC-25 mixes using stabilized RCA and lime (doses lime: water 1:1 and 1:2) were compared with those obtained from the mix using naturally occurring aggregates (called the control mix) and the mix which was replaced by non-stabilized RCA material.