Study Enhancing the Rutting of Flexible Pavement by Adding Selected Polymers into Asphalt Mixes

Rutting in flexible pavement is one of the main permanent deformation which appears in most Iraqi roads owing to high temperature and the increase in axial excessive heavy trucks load, these combined conditions cause a major impact on the road performance. The polymers used as additives to improve the properties of asphalt and, that leads to achieve high quality asphalt mixture. This humble research focused on finding the suitable treatment for such issue by using SBS and HDPE. Whereas 5 percent for each polymer was used (2%, 4%, 6%, 8% and 10%) by weight of total mix. A different percentage of polymers were used in order to achieve the best additive percent which was proved to be (8% HDPE, 6% SBS) for wearing (III A) layer and (6% HDPE, 2% SBS) for binder layer. As well as the results showed that using the optimum percent of additives for each layer of asphaltic mixture and test it as one specimen formed from two layers, has decreased the rutting percent by (72%, 65%) for (HDPE, SBS) respectively for each type of additives at (40ºC).