Ali Asghar Roghanizad - Chemical engineering faculty of Amirkabir Univrsity
Azam Jalali - Polymer engineering faculty of Amirkabir Univrsity.
Taghi Bahrami - Civil and Enviromental engineering faculty of Amirkabir Univrsity
Seyyd Hossein Edalati Alavi - Polymer engineering faculty of Amirkabir University.

Bitumen has been widely used as a binder in pavement mixtures. Certain binder properties are required in this application to prevent the occurrence of rutting, fatigue and thermal cracking. Today's increasing loads, greater traffic volume and the need for better, longer-lasting roads demand better service from paving materials and considerable research in recent years has focused on improving the functional properties of bitumen. The use of polymeric material in bitumen mixture has been shown as a good method to improve the performance of the mixture. In this work ground tire rubber in combination with precipitated calcium carbonate were used to improve performance of conventional asphalts. Bitumen mixtures contained different amount of these modifiers were prepared. Then the effects of the used modifiers on bitumen performance were studied through measuring degree of penetration and softening point of the mixture. The modified bitumen was used in the asphalt and its performance was studied and reported.

Bitumen, ground tire rubber, P.C.C., modified