[01] Saad Issa Sarsam, Transportation Engineering, Department of Civil Engineering, College of Engineering, University of Baghdad, Baghdad, Iraq.

In this work, an attempt has been made to prepare the modified Asphalt cement for pavement construction in the laboratory by adding nano materials (silica fumes , and hydrated lime) to each of the two penetration grade Asphalt cement (40-50 and 60-70). Two different percentages of each of the above-mentioned additives have been tried using continuous stirring and heating at 150 -160 ºC for 45 minutes. The silica fumes percentages were at the range of (1-2) %, with 1% increments, the hydrated lime was at the range of (10-20) %, with 10 increments. The prepared modified Asphalt cement specimens were subjected to physical properties determination; the penetration, softening point, ductility, elastic strain recovery, and rotational viscosity. The rheological properties of the modified Asphalt cement such as penetration index, temperature of equivalent stiffness, stiffness and penetration viscosity number were calculated. The effect of each ingredient of the modified asphalt cement on physical, rheological, and elastic properties have been studied and discussed. It was concluded that the silica fumes and lime have beneficial effects on the overall properties of the modified Asphalt cement.

Asphalt Rheology, Modified Asphalt Cement, Silica Fumes, Lime

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