PURPOSES : The objective of this study is to evaluate the feasibility of applying properties of asphalt binder other than absolute viscosity (AV) to evaluate the rejuvenation level of the binder from reclaimed asphalt pavement (RAP) in recycled asphalt mixtures (RAMs). METHODS : The G*/sin and critical temperature (CT) for determining high performance grade by DSR, and the large molecular size (LMS) using gel-permeation chromatography (GPC) were measured simultaneously with the AV of two virgin asphalt binders (58–22 for RAM and 64–22 for normal mix) and recovered binders from a RAP and four RAMs. Based on mix design, 20%, 30%, 40%, and 50% recycled RAMs were prepared, and the deformation strength (SD) of the RAMs were measured. The AV, LMS, G*/sin , and CT were measured from the recovered binders from each RAM of the SD-tested specimens. Regression analyses were performed between the LMS and AV, G*/ sin and AV, and CT and AV to determine the correlation of each property with the AV. The feasibility of evaluating the rejuvenation level of the RMA binder using the three properties (LMS, G*/sin , and CT) was evaluated. Regression analysis was performed between SD and AV, and the feasibility of using SD instead of AV ≤ 5,000 poise (p) was analyzed to evaluate the rejuvenation level of the RAM. RESULTS : The AV, LMS, G*/sin , and CT of RAM binders increased with the recycling ratio. Mixes with recycle ratios of 20% and 30% satisfied the AV ≤ 5,000 p criterion, unlike mixes with higher recycle ratios. The regression analysis results showed that the R2 values between the LMS and AV, G*/sin and AV, and CT and AV exceeded 0.96. Since these regressions showed extremely high R2 values, it can be inferred that the estimation of binder rejuvenation level using the LMS, G*/sin and CT, i.e., instead of the AV criterion, is applicable. Because SD exhibits high correlation with the binder stiffness, and the regression between SD and AV indicated R2 > 0.98, SD can be applied instead of the AV for binder rejuvenation level estimation. The main advantage of using the LMS and SD is to estimate the binder rejuvenation level without recovering the binder from the mix. CONCLUSIONS : For the binder rejuvenation level estimation of recycled mixes, it is concluded that the LMS by GPC and G*/sin and CT by DSR, and SD can be applied instead of the AV criterion. However, since this study was performed using limited materials, further studies involving many other materials may be performed to generalize the current conclusion.

PURPOSES: This study evaluated the effect of fog seal treatment utilizing an agricultural oil-based asphalt concrete sealant (ABCS) on the long-term performance of an asphalt pavement. METHODS: Fog seal treatment using ABCS was applied on 800 m of the pavement section in the test section with a total length of 2,400 m; the remaining pavement section was not considered for this treatment. A series of laboratory and field tests were conducted on both sections, including a Marshall stability test, penetration test, viscosity test, skid resistance test, and pavement surface macrotexture test. In addition, the pavement condition index (PCI) was determined 8 years after the ABCS application to evaluate the effect of the ABCS treatment on the pavement’s long-term performance. RESULTS : The ABCS-treated section exhibited a PCI of 75, whereas the non-treated section exhibited a value of 64. Furthermore, a MicroPAVERTM‚ pavement management system determined that the pavement deterioration rates (i.e., drops in PCI) were 3.6 and 5.1 per year for the ABCS-treated and non-treated sections, respectively. CONCLUSIONS : The results of the series of laboratory and field tests revealed that the ABCS treatment increased the pavement performance life by approximately 3.5 years.

본 논문은 가열 재생아스팔트 흔합물의 성능을 향상시키기 위한 방법을 개발하기 위한 연구의 일부분이다. 새로이 개발된 혼합 방법은 회수 아스팔트 포장의 기존 바인더를 훨씬 많이 회생시켜 재생 혼합물에서 균일한 바인더의 정도를 갖게 한다. 본 연구의 목적은 새로이 개발된 혼합 방법으로 제조된 재생아스팔트 혼합물의 소성변형 저항 특성을 평가하는 것이다. 두 종류 골재(편마암 화강암), RAP의 두 가지 함량(15, 30%), LDPE의 두 가지 첨가량(0, 6%)를 이용하였으며, 혼합방법은 바인더의 불균등 상태를 개선하기 위한 두 가지 방법, 즉 일반적인 기존의 A 방법과 새롭게 개발한 F 방법을 이용하였다. 재생 혼합물 내의 바인더 산화 정도의 차를 조사하기 위하여 GPC분석을 실시하였고, 흔합 방법에 따른 소성변형 저항성을 평가하기 위하여 각 혼합 방법에 따라 제작한 재생 흔합물을 휠 트랙킹 시험과 변형강도를 측정하였다. 소성변형 저항 특성과 변형강도와의 상관관계는 기존의 A 방법보다 새롭게 개발된 F 방법이 더 높게 나타나, F 방법으로 제조된 혼합물의 품질이 보다 일관성 있는 소성변형 저항성을 나타내는 것을 알 수 있었다.