Concreto alternativo para pavimentos rodoviários

Abstract

In order to find an alternative concrete for road paving, it was in search of materials able to be reused and/or extracted from the natural environment with ease. For the manufacture of alternative concrete, the alkali-activated cement was chosen as the binder for the mixture. It was necessary to carry out tests in laboratories to characterize the raw material (flying gray) to then make the alkali-activated cement that served as a binder for the aggregates, 100% of asphalt binder and Portland cement being replaced. They were framed as the "C" band of the DNIT and then dosed and added to the binder. The samples in this study were based on the steering wheel gray activated with a sodium hydroxide solution, ranging from 12 to 16mol, the alkali activator and the ratio of activator solution to steering wheel gray of 0.50 to 0.55 (by mass), as well as the use of a thermal cure of 65ºC and 85ºC respectively, and aggregates for the 2 molarities were added in proportions. In addition, samples were performed for Marshall stability and fluency tests, compression and tensile strength in bending, testing 3 test bodies for each test age (1, 3 and 7 days). High potential of samples of 16mol with satisfactory resistance was demonstrated in all tests carried out. However, in the samples of 12mol it was possible to verify a decrease in resistance over the days in the tensile strength test in bending, and further studies are necessary to understand the behavior of these samples when subjected to this type of effort. With the results obtained, the great potential of the alkali-activated cement for use in road pavement was verified, however, requiring a more in-depth analysis to obtain new parameters in order to find the ideal dosage that meets the current road pavement standards.