The SMA mixtures are characterized by a high void ratio, which favors binder draindown. In order to avoid this effect, fibers are added to the mixture, which in this case came from Curauá da Amazônia (Ananas erectifolius). The final composition studied resulted in 75% coarse aggregate, 15% fine aggregate, 10% filler, 0.3% of the Curauá fiber residue, and CAP contents equal to 6.50% and 6.88% for the formulations with SMA-Crushed Stone (reference) and SMA-construction and demolition waste (alternative), respectively. The results showed for the Tensile Strength that the composites with CDW reached higher results. The Resilient Modulus values presented small variations for the set of compositions in all loading levels at a temperature of 25°C. However, at a temperature of 40°C, the aforementioned parameter presented decreases in both researched formulations. In general, at all levels examined, higher results were observed for the alternative mixture (SMA-CDW). It is noteworthy the highest results of this parameter when comparing the compositions with the Curauá fiber residue and the formulations mentioned in the literature, with the presence of other types of fibers. Regarding the increase in temperature, there was a decrease in results for both mechanical parameters (TS, DM), but with lower losses for the SMA-RCD composition.
Soil stabilization for use in pavement sublayers has been established in Geotechnical En-gineering as an option for pavement construction. In this context, certain alternative materials stand out, such as coal and biochar, which are able to fulfill this function when added to the soil, being the object of study in the present research. These products originated from char-coal furnaces and biomass carbonization under low oxygen atmosphere. In the present study we evaluated the natural soil and compositions according to the four-point bending test, for simulating vehicle tire-loads on the pavement. For this purpose, we molded prismatic speci-mens with natural soil (NS) typical of the Amazon region, with natural soil-10% charcoal (SCH) and soil-10% biochar (SBC). It was verified that the soil-biochar mixture (SBC) pre-sented better results, culminating in higher values of complex modulus when compared to the natural soil (NS) and soil-charcoal mixtures (SCH). Regarding the phase angle parameter and the analyzed set (NS, SCH e SBC), values close to zero were observed. Therefore, this article presents the possibility of using alternative materials for executing road systems with better performance.
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