Performance Analysis on Modified Bitumen by Nature Rock Asphalt

Abstract

Taking the natural rock asphalt as the modifier, the technical properties of Esso AH-70 base asphalt, affected by natural rock asphalt, were studied in a series of experiments. The performance of modified asphalt for different dosages was systematically analyzed and compared through a dynamic shear rheometer, a bending beam rheometer and a Brookfield rotary viscometer. The results indicate that the softening point and the viscosity of modified base asphalt are raised; the penetration and the ductility are reduced and the anti-rutting factor is increased; the high temperature stability is obviously enhanced; and the thermal sensitivity is greatly reduced. With an increase in the mixing amount, the change tendency of natural rock asphalt becomes increasingly evident. When the mixing amount of rock asphalt is controlled at 2%∼8%, it has no considerably adverse influence and the low temperature performance of asphalt binder can still satisfy the pavement requirements in all but extreme low temperature conditions.