Evaluación de la Resistencia Mecánica de una Mezcla Asfáltica Tibia Sustituyendo Parcialmente el Agregado Pétreo Grueso, por Agregado Reciclado de Concreto (ARC)

Abstract

Hot-dense mixes today have some considerable drawbacks. Its manufacture at high temperatures implies a high energy consumption and considerable environmental pollution. In addition to the high manufacturing cost, these problems have led to the search for viable, effective and reasonable options to reduce environmental impacts. Likewise, the excessive exploitation of natural aggregates also causes a negative impact on the conservation of the natural environment. Therefore, it is interesting to use recycled concrete aggregates (ACR) to partially replace elements such as stone aggregates that make up the asphalt mix. In this context, the present study carried out an experimental period where the result of a recycled warm asphalt mix was evaluated. This mixture was manufactured by incorporating the HUSIL additive to the asphalt, as well as the partial replacement of 21% of the coarse fractions (½" and ¾" sieves) of the stone aggregate by ACR. The ACR was obtained in a waste separation plant authorized by the Urban Development Institute (IDU) in Bogotá D.C. Monotonic load tests were carried out, such as the Marshall and indirect tensile tests and dynamic load tests, which included the resilient modulus and Cantabrian wear. For the preparation of the mixtures, CA 60-70 asphalt was used, and the natural aggregate came from the CONCRESCOL S.A. asphalt plant. According to the answers obtained, it can be thought that a more efficient performance is obtained since it reduces the mixing temperature by 25°C, using the HUSIL additive and replacing 21% of the coarse fraction of the stone aggregate with ACR (replacing the ½" and ¾" sieves). Under these conditions, this product presents a significant increase in its hardness, both in monotonic and dynamic load. In addition, it presents a high resistance to the effect caused by humidity and a better capacity to resist permanent deformations in relation to the control mixture.