الفهرس 
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Abstract
The increase in traffic volume together with the random maintenance programs due to the lack of funds and experiences lead to rapid deterioration of the road network in the developing countries. This phenomena causes the worsen of pavement deformation mainly fatigue, creep, cracks and rutting distresses especially in hot climatic conditions due to the high sensitivity of the asphalt materials. The main objectives of this thesis are to employee the waste rubber tyres to replace fine aggregates in asphalt mixtures as well as enhancing the asphalt binder properties using polyethylene (Poly).Tried percentages of poly were 2, 4, 6 and 8% by the total weight of bitumen, while rubber percentages were 0.5, I and 2% by the total weight of mixture as a percent of fine aggregates. So using the rubber reduces the demand for fresh aggregates and sustains the environment while using the poly enhances the pavement rigidity to resist rutting.
TV•io gradations were used in this study the maIn gradation named (gradation A) and the second gradation (gradation B) to validate results of gradation A. An experimental study was carried out on 140 Marshall Specimens of hot mix asphalt (HMA) and four specimens (slabs) for wheel track test. The main conclusions can be summarized as; adding of polyethylene increased the stability to a peak value and then reduced, while, flow generally decreased such that the rigidity (stabilitylflow) generally increased. The maximum increase in stability and decrease in flow at the optimum polyethylene content (O.P.C) of 4% are 17.44% and 2.9% respectively. The addition of rubber to the asphalt modified mixtures, increased stability, flow, the air voids (AY %) and voids in mineral aggregates (YMA %). Also using rubber changed the density.