Enhanced Performance of Asphalt Mixtures by Adding Recycled Rubber from Damaged Car Tires

Due to the problems that the Libyan road network is exposed to, such as cracks and ruts resultingfrom increased loads on the roads. Therefore, research and development in this field aims toimprove the properties of asphalt and enhance its performance on roads through the use ofinnovative technologies and improved materials. In this research, the properties of asphalt mixturesmodified with rubber resulting from recycling damaged rubber car tires were studied, in order toimprove their performance in terms of stability and flow, which enhances their ability to deal withexpansion and contraction resulting from thermal changes and traffic movement on the roads. Theresults showed that when rubber was added to the asphalt mixture, all properties of the asphaltmixture improved, as the stability value increased by 15.8% when rubber was added, while theflow value decreased by adding rubber. By 14.5%. The results also showed that the bestpercentage of bitumen was 5.6%, and the best percentage of rubber added to the asphalt mixturewas 9%. After extracting bitumen from the modified mixture with 9% rubber, it was found that thepercentage of effective bitumen was 5.9%, which was 0.3% more than the optimum percentage ofbitumen. Therefore, the percentage of bitumen decreased by 0.3% to be within the specifications.Based on the research results, we recommend using 9% rubber in the modified mixture in theasphalt mixture industry in Libya due to its benefits on the durability of the pavement, resistance torutting, and reducing road maintenance. Adding rubber reduces the costs of road maintenance andpaving by reducing the percentage of bitumen in the asphalt mixture.