الفهرس 
Introductionيوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
Heavier loads and higher traffic volume demand higher performance of pavement. Excellent performance of pavement requires bitumen that is less susceptible to high temperature rutting or low temperature cracking. To improve its properties, Bitumen needs some modifiers such as polymers.
This study is in favour of using polymers (polypropylene and Polyvinyl chloride) as modifiers because of low-cost situation and having good correlation with asphalt pavement. The conventional bitumen (60/70) penetration grade was used in this research, modified with Polypropylene (P.P) at four different modification levels namely 1%, 3%, 5% and 7% by weight of the bitumen and Polyvinyl chloride with 2%, 4%, 6% and 8% by weight of the bitumen.
The conventional test such as penetration test and softening test dna
epecsren ncrtcele was used at first to determine physical properties of modified and un modified bitumen and then marshal mix design was used to determine the optimum bitumen content and then mechanical test such as Marshall Stiffness, compressive Strength, Indirect Tensile Strength and Critical energy Release rate were conducted in this research.
The results indicated that, the addition of polymers (polypropylene and polyvinyl chloride ) generally improved the mechanical properties of the mixture Regardless of the percentage of polymers that added and ( PP) content of 5% and (P.V.C ) content of 8% by weight of asphalt mixture can be recommended for the improvement of the performance of asphalt concrete mixtures and it can be noticed that the performance of (P.P)-modified asphalt mixtures is better compared with (P.V.C) modifier because it has the highest Marshall Stiffness, indirect tensile strength and unconfined compressive strength .
Experimental testing has revealed the enhancement in the physical and mechanical properties of bitumen and asphalt mixtures when Polymers were added.