Estudo laboratorial da utilização de material fresado em misturas asfálticas recicladas a quente

Abstract

The use of recycled materials can become a constructive application with good acceptance in the road sector, and is a great contribution to the sustainability policy. In this scenario, the study of economic and sustainable techniques for execution, construction and maintenance of highways, forces a survey in which they can find alternatives to the use of materials that reduce energy consumption, taking into account also the environmental appeal. Therefore, this is an objective research on the study of a way to use, reuse, and improve the use of the recycled asphalt pavement (RAP) in hot asphalt mixtures. This is possible due to the RAP's recycling process being a viable option to replace conventional pavement materials. Then, the RAP becomes an alternative when someone wishes to improve the properties of a material, called particle size stabilization, aiming at a correct particle size and obtain a material with greater strength, efficiency and lower cost. To achieve the purpose of this study, laboratory tests were made to evaluate the mechanical properties and adhesiveness of mixtures containing 10% addition of RAP, 20% and 30%, compared to a reference mix without the RAP addition. Additionally, the initial use of the Bailey method was an important factor to the formation of the mixtures and selection of the aggregates used to Superpave methodology to design dosage strength and preparing of the samples. For mechanical evaluation were used resilient modulus tests (RM) and to review viscoelastic were used uniaxial dynamic modulus test. In addition, the indirect tensile strength tests were performed (RT) and Flow Number (FN) and damage tests induced moisture through the Modified Lottman test and wear a Cantabro abrasion, for evaluation of the properties of adhesion and cohesion of the mixtures, respectively. So after obtained these results, it was possible to make an analysis of the use of these hot mix asphalt recycling hot pavements, as well as assess how much conventional mixtures can be improved with the inclusion of recycled material, replacing virgin aggregate. Then, it was possible to infer that the mechanical evaluation showed positive results with the addition of RAP compared to a reference blend. It´s possible to reduce the new binder content between 13 and 37%. The results showed that RM stiffness and indirect tensile strength increases with RAP amount. Furthermore, the FN test results showed reductions on permanent deformation and rutting of the RAP´s mixtures. Through the master curve obtained by dynamic module, along with modeling 2S2P1D, it was found that the CAF10 mixture unexpectedly had stiffness greater than the CAF20 mixture, which has 20% more RAP than the previous.