Cold recycled asphalt has been utilized to overcome high energy consumption and working temperature and low recycled pavement material percentage in hot mix asphalt and concrete pavement [1]. Up to dates, asphalt recycling on site called as Cold In-Place Recycling (CIR), Cold Central Plant Recycling (CCPR) and even hot recycling technologies have been developed and applied to the fields, but limitations such as poor adhesion between gravel and asphalt, slow hydration time, bleeding pavement are reported, respectively [2, 3, 4]. Among these issues, hydration time and initial strength in application are all related to the property of mineral filler influencing the mechanical property of pavement mixture. Due to these reasons, there have been continuous needs to develop new mineral filler to overcome previously reported issues by with the respects of mineral composition, hydration reaction and surface reaction enhancement. In this study, several natural minerals such as alumina, silicate, and calcium oxide were utilized as raw materials and following characterizations using SEM, EDS, XRD, and BET were performed to evaluate materials properties and suggest research directions for the optimum mineral filler development.

PURPOSES: The new waste management policy of South Korea encourages the recycling of waste materials. One material being recycled currently is tire-derived fuel (TDF) ash. TDF is composed of shredded scrap tires and is used as fuel in power plants and industrials plants, resulting in TDF ash, which has a chemical composition similar to that of the fly ash produced from coal. The purpose of this study was to evaluate the properties of an asphalt concrete mix that used TDF ash as the mineral filler. METHODS: The properties of the asphalt concrete were evaluated for different mineral filler types and contents using various measurement techniques. The fundamental physical properties of the asphalt concrete specimens such as their gradation and antistripping characteristics were measured in accordance with the KS F 3501 standard. The Marshall stability test was performed to measure the maximum load that could be supported by the specimens. The wheel tracking test was used to evaluate the rutting resistance. To investigate the moisture susceptibility of the specimens, dynamic immersion and tensile strength ratio (TSR) measurements were performed. RESULTS : The test results showed that the asphalt concrete containing TDF ash satisfied all the criteria listed in the Guide for Production and Construction of Asphalt Mixtures (Ministry of Land, Infrastructure and Transport, South Korea). In addition, TDF ash exhibited better performance than that of portland cement. The Marshall stability of the asphalt concrete with TDF ash was higher than 7500 N. Further, its dynamic stability was also higher than that listed in the guide. The results of the dynamic water immersion and the TSR showed that TDF ash shows better moisture resistance than does portland cement. CONCLUSIONS : TDF ash can be effectively recycled by being used as a mineral filler in asphalt, as it exhibits desirable physical properties. The optimal TDF ash content in asphalt concrete based on this study was determined to be 5%. In future works, the research team will compare the characteristics of asphalt concrete as function of the mineral filler types.