Effect of rheology of modified bitumen to the permanent deformation performance of asphalt mixture

With increasing truck traffic and tire pressure, the excessive permanent deformation or rutting become a major concern in asphalt concrete pavements. Road safety is the main concern of rutting. There is reduced frictional characteristics for vehicles, e.g., wheel path flushing, changing lanes becomes hazardous and water ponds in wheel paths. It is therefore important to characterize the permanent deformation behaviour of asphalt mixes before they are placed in roadways. Improving the characteristic of bitumen can support the ability of asphalt mixture to be more resistant to permanent deformation. This paper focuses on the characteristics of permanent deformation of asphalt mixture with the asphalt modified. Modified bitumen with the natural asphalt Buton of 5, 10 and 15% by weight of base bitumen gave positive results on bitumen stiffness as indicated by decreasing penetration values and softening point, as well as complex shear modulus (G*). The phase angle (δ) decrease that correlated with the resistance of bitumen after modified by Buton Natural Asphalt-Rubber (BNA-R). The result of wheel tracking test for asphalt mixture with bitumen modified shows the decreasing of rut depth at the vary temperature tests. The addition of BNA-R applied to the virgin bitumen causing the rut depth of asphalt mixture decrease.