Study the effect of adding crumb rubber on the performance of hot mix asphalt

The recycling of materials has a huge impact on the economy and the environment; therefore, the recycling of steel, aluminium, plastic and other materials have been encouraged to use in construction materials. Crumb rubber is one of these recyclable materials and has been proposed as one of the pavement components in this study since the crumb rubber can improve the pavement performance and is also considered as waste material. The most significant motivation behind use of the CRM in the pavement industry was the enhancement of pavement performance and extended service life of the pavement by increasing the resistance to moisture damage and resistance to permanent deformation and improved resilient modulus. Therefore, this study focused on the effect of CRM binders on the performance and mechanical properties of the hot mix asphalt. The CRM binders were produced by mixing asphalt binder with various percentages of crumb rubber in a wet method. There are several laboratory tests performed to assess the properties and performance of asphalt mixture, which contains various percentages of crumb rubber, and this, includes; the Marshall properties, indirect tensile strength test, moisture damage test, resilient modulus test and permanent deformation test. In this study, the results of the investigation showed that the addition of crumb rubber (CR) to the asphalt binder and used in the mixture was useful in increasing the resistance to moisture damage, improving the resilient modulus and enhancing the potential to resist permanent deformation that happens in the surface layer of the pavement as a result of increased traffic loading.