PERFORMANCE ANALYSIS OF RECYCLED HOT-MIX ASPHALT (HMA-RAP), WARM-MIX ASPHALT (WMA), AND RECYCLED WARM-MIX ASPHALT (WMA-RAP) AC-BC USING EVOTHERM® ADDITIVE

• Main Author: Imanuel, Ivan
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/64109
• Institution: Institut Teknologi Bandung

Flexible pavement industry today has problems due to limited material resources and production efficiency along with its increasing demand. Recycled asphalt (RAP) and warm mix asphalt (WMA) appear as environmentally friendly pavement technologies. Both RAP and WMA, require additives to modify the properties of the asphalt binder used. Evotherm as a WMA additive has the potential to be used as a rejuvenator. This study attempts to measure the effect of Evotherm on the characteristics of asphalt and RAP, as well as its effect on the performance of asphalt mixtures, which include resilient modulus, fatigue, and permanent deformation. This study aims to examine the effect of Evotherm on the characteristics of 60/70 penetration asphalt binder and RAP asphalt binder, analyze the optimum Evotherm content, determine the optimum binder content, and measure the performance of AC-BC mixtures containing Evotherm additive. Evotherm is used as an additive in WMA and a rejuvenator in RAP. The properties of the materials to be used in the asphalt mixture were tested according to the Indonesian General Spesification for Highway 2018 revision 2. The Evotherm content in 60/70 asphalt binder was determined at the lowest mixing viscosity and temperature while the Evotherm content in RAP asphalt was determined at a level that resulted in 60-70 asphalt penetration. The aggregate used is calculated to normalize the volume gradation of the RAP aggregate. There are six types of mixtures made, namely HMA, HMA-RAP 30%, HMA-RAP 35%, WMA, WMA-RAP 30%, and WMA-RAP 35%. The optimum asphalt content (OBC) of the asphalt mixture was determined by the Marshall method. Resilient modulus was tested using the Umatta apparatus at temperatures of 25°C, 40°C, and 55°C. The permanent deformation test used the Hamburg Wheel Tracking Device at 60°C, while the fatigue test used the Beam Fatigue Apparatus at 20°C. RAP contains aged asphalt binder of 5.37% with penetration of 17.4 dmm. As WMA additive, Evotherm succeeded in reducing the viscosity and mixing temperature of 60/70 asphalt pen from 159°C to 147°C with a concentration of 2%. As a rejuvenator, Evotherm succeeded in increasing the penetration of RAP asphalt to 62 dmm with content of 15%, but the ductility, loss on heating, and properties after short-term aging were worse than that of 60/70 penetration asphalt binder. The gradation of the RAP aggregate is finer than the required limit for the AC-BC mixture so that it requires more coarse aggregates. KAO increases as Evotherm and RAP are added to the mix. Stability and flow also increased with increasing use of RAP in the mix. However, the mixtures become more difficult to compact. The higher the temperature of the mixture, the lower its stiffness. The resilient modulus becomes higher in the mixture with RAP while the large amount of Evotherm in WMA decreased the modulus. The resistance to permanent deformation is highest in HMA-RAP while WMA is the most prone. WMA-RAP30% is more resistant to permanent deformation than HMA, while WMA-RAP35% is more prone than HMA. The highest fatigue resistance was obtained at WMARAP30% while the lowest fatigue resistance was obtained at WMA at low strain levels and HMA-RAP30% at high strain levels.