PURPOSES: The objective of this study is to investigate the properties of recycled asphalt binders with five different rejuvenators, in order to evaluate the applicability of the recycled asphalt binders compared with the original asphalt binder.
METHODS: In order to simulate recycled asphalt binders, fresh asphalt binders are aged by various Superpave aging procedures, such as the rolling thin-film oven (RTFO) and the pressure aging vessel (PAV). Then, selected rejuvenators are added to the aged asphalt binders in the amount of 5%, 10%, and 15%. The asphalt binder properties are evaluated by the dynamic shear rheometer (DSR), the rotational viscometer (RV), and the bending beam rheometer (BBR). In this study, AP-5 (penetration grade 60-80, PG 64-16) asphalt binder is used. A total of five types of rejuvenators are employed.
RESULTS AND CONCLUSIONS : When considering aged asphalt without a new asphalt binder, it seems that the percentage of rejuvenator used in Korea is a bit too low, and that it fails to possess the characteristics of the original binder. From the current practice of evaluating the properties of recycled binder based on penetration ratio only, the amount of rejuvenator required is similar for the long-term-aged binder, but is excessive for the longest-term aged binder, causing deterioration of workability and stiffness of the recycled binder.

1. INTRODUCTION
2. OBJECTIVE
3. METHODOLOGY
4. ANALYSIS OF TEST RESULTS
5. CONCLUSION AND RECOMMENDATION
ACKNOWLEDGEMENTS
REFERENCES

• Kim, Yeong Min(Member·Korea Institute of Civil Engineering and Building Technology·Senior Researcher) | 김영민
• Im, Jeong Hyuk(Member·Korea Institute of Civil Engineering and Building Technology·Senior Researcher·Ph.D.) | 임정혁 Corresponding Author
• Hwang, Sung Do(Member·Korea Institute of Civil Engineering and Building Technology·Research Fellow·Ph.D.) | 황성도
• Jeong, Kyu Dong(Member·Korea Institute of Civil Engineering and Building Technology·Senior Researcher) | 정규동
• Rhee, Suk Keun(Member·Kyung Hee University·Professor·Ph.D.) | 이석근