Journal of Engineering Science and Technology (Aug 2016)
PERFORMANCE PROPERTIES OF ASA POLYMER MODIFIED ASPHALT BINDERS AND MIXTURES
Abstract
Asphalt is commonly used as a binder in the construction of highways and runways, due to its good viscoelastic properties, natural asphalt cement does not have sufficient strength to resist sudden stresses of excessive loading or stress from low and high temperatures. Therefore, modification of asphalt is necessary in order to improve its material temperature sensitivity, adhesion, durability, oxidation and aging resistance. The property of base asphalt and polymer modified asphalt binders and mixtures has been characterized using the conventional tests and dynamic creep tests. It has been found that, the addition of Acrylate Styrene Acrylonhrtilrei (ASA) polymer content has magnificent influence on the properties of the asphalt binders and mixtures. The temperature susceptibility of modified asphalt binders was reduced compared with base asphalt binder as the penetration increase and softening point decrease. The reduction in penetration was up to 69%, while the improvement in softening point was up to 19%. Moreover, it was approved from the storage stability test that, the ASA polymer has a great compatibility with asphalt binder up to 5% ASA. In addition, it was observe reduction in permanent deformation of modified asphalt mixtures with increase of modifier up to 5% ASA, which lead to better resistance to rutting at high temperatures, and the reduction was up to 36%. As a result, the modification of asphalt binder and mixture with ASA polymer can be considered a proper alternative technique to improve the properties of asphalt binder and mixture and 5% ASA was the optimum content of the modifier.