Laboratory Evaluation on the Performance Comparison between OGFC Asphalt Reinforcement with Fibers and Modified with Nanosilica

摘要

Open-graded friction course (OGFC) is a mixture with gap-graded aggregate that is used inpavement surfacing. This research proposes methods to improve the durability and structuralcontribution of OGFC mixtures through laboratory performance testing. A draindown test, aCantabro test, a permeability test, and an indirect tensile strength test were used to evaluatethe performance of OGFC mixtures. The main parameters of this research specify optimumbitumen and desirable air voids, maximum reduction of draindown and abrasion loss, and retainedtensile strength ratio. It was observed that the effect of fiber in both states on bitumenpercentage caused increased sensitivity to oxidation of the asphalt mixture; however, the effectof nanosilica on the reduction of sensitivity to oxidation was considerable. The effect ofglass fiber in enhancing tensile strength was far higher than that of basalt fiber. In both states,nanosilica caused improved tensile strength of the mixture. Additionally, the moisture sensitivityof the OGFC mixtures with glass fiber was far better than that of the basalt fiber, andaddition of nanosilica caused further improvement. The results showed a negative effect of theaddition of basalt fiber alone in the asphalt mixture with a higher between percentage, necessitatingthe addition of nanosilica in conjunction with basalt fiber.