Buton Rock Asphalt (BRA) is a processed natural rock asphalt from buton island, Indonesia. It has double advantages: it will act as an additional filler and most important is that, it will act as a bitumen modifier. Acting as a bitumen modifier (additive), BRA will notably improve the properties such as adhesion, softening point, dynamic stability, splitting and reactive strength; particularly will suit for such severe traffic loading condition in an extreme temperature environment (hot/cold weather condition).