The Impact of Utilizing Waste Tire and Solid Natural Rubber as Asphalt Binder Substitutions on the Asphalt Concrete-Wearing Course Mixtures

Roads are a necessary component of infrastructure for human life, particularly for mobility and meeting needs.The majority of roads in many locations are made of flexible pavement, which mainly consists of gravel and asphalt.Although this pavement is designed to support vehicle weight and is not immediately absorbed by the subgrade layer, damage may occur over time.The two main causes of road deterioration are variations in temperature and heavy loads.One approach to addressing this issue is through the use of modified asphalt binders.This study aims to evaluate the impacts of using waste tires and solid natural rubber (KACR) as materials for modifying asphalt binders.Asphalt rheology testing using a dynamic shear rheometer, characterisation testing with the Marshall method on asphalt mixtures, and stiffness modulus testing with the Universal Testing Machine were conducted to assess their behaviour.KACR was used as a replacement for up to 7%-10% of the asphalt binder's weight.Test results showed that utilising KACR as an asphalt binder modification material can reduce the phase angle and increase complex modulus values at high temperatures.Furthermore, based on Marshall test results, it was observed that incorporating KACR into asphalt mixtures increased stability by 26.16%-27.29%while reducing flow values by 10%.Stiffness modulus test results also indicated an increase ranging from 32.30%-88.99% at a temperature of 25 o C, with even higher increases of 67.14%-105.69%possible at a temperature of 40 o C.