Determining the Optimal Percentage of Gilsonite Additives in Bitumen Using Analytical Hierarchy Process (AHP)

The high volume of construction using asphalt in Iran and the weakness of the bitumen produced in the country¡ during the time of utilization has caused several kinds of failure. Gilsonite in class¡ reform of the bitumen to the hydrocarbons belong¡ a substance that can be in the modification of bitumen and its subsequent correction of mixtures of asphalt used especially with the increase of pure bitumen price¡ the use of organic bitumen in asphalt production has a direct economical benefit for the country. On the other hand with the increase of bitumen and asphalt property produced¡ the quality and the life of road surfaces will increase. The effects of organic bitumen on common functional properties of bitumen such as softening point¡ penetration ¡ viscosity ¡ gum plasticity ¡ weight loss ¡ weight gain and boiling point. In this research¡ by adding Gilsonite to the bitumen samples with the percentage of 0¡ 2¡ 4¡ 6¡ 8 and 10 after performing several experiments the most suitable criteria of optimal additives were determined using Analytical Hierarchy Process AHP methodology.