Experimental evaluation of different additives applied in a hot dense mix asphalt MDC — 19

Due to the constant climate change and the high demand of the vehicle fleet, as well as the exponential growth of traffic, there is now a necessity to experiment and include innovative materials to improve the mechanical performance of bituminous mixtures. The use of new additives is an interesting alternative to reduce the different damages generated by traffic loads, climate agents and any other phenomenon; and thus, be able to prolong its useful life. In this research, different additives were evaluated experimentally in a hot mix asphalt with a maximum nominal size of 19 mm (MDC-19). The additives selected as modifiers of the mixes were: hydrated lime (HL), coconut fiber (FC), polypropylene fiber (PP) and grained crumb rubber (GCR). A total of 72 specimens were manufactured; twelve of them were made to determine the optimum asphalt content by using the Marshall methodology and the remaining 60 were made for the experimental evaluation of the bituminous mixtures. The experimental tests carried out were: Marshall test, indirect tension test and particle loss test; these following the INVIAS regulations. From the experimental results, it was found that the modified mixture with HL was the most favorable and promising additive in the hot dense asphalt mixture, This is because it presents improvements in mechanical performance as it has greater resistance to deformation in addition to good stability and less moisture damage, which is a good alternative for the overall performance in the mixture.