• 한국도로학회논문집
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• 제16권4호
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• pp.45-50
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• 2014

PURPOSES : The objective of this study is to analyze the performance of anti-stripping agent depending on its type and content to reduce pothole, an increasing pavement distress due to abnormal climate intensity. METHODS : In the past years, U.S and many countries in Europe use hydrated lime and liquid anti-stripping agent in asphalt mixtures. Hydrated lime or liquid anti-stripping agent is substituted for filler and binder, respectively, to improve the anti-stripping property of asphalt mixtures. To investigate this, indirect tensile strength test was performed and TSR values were compared for different content of hydrated lime and types of liquid anti-stripping agent in asphalt mixture. RESULTS : Test results indicate that hydrated lime remarkably increased the asphalt mixture performance on anti-stripping denoted by the increased in TSR values from 55% to 100%. Liquid anti-stripping agent also increased the value of TSR but not significant. In addition, depending on the types of aggregate, TSR values and effect of liquid anti-stripping were different. CONCLUSIONS : Using anti-stripping agents improve the anti-stripping property of asphalt mixture especially hydrated lime; however, more experiments should be conducted to improve the reliability about the effect of liquid anti-stripping agent.

• 한국도로학회논문집
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• 제19권2호
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• pp.127-135
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• 2017

PURPOSES: The objective of this study is to evaluate the effect of anti-stripping on asphalt mixtures constituting anti-stripping agents. METHODS : Based on the literature review, asphalt mixture added with anti-stripping agents was prepared, and these asphalt mixtures were evaluated for anti-stripping properties for each anti-stripping agent through various lab tests, namely, tensile strength ratio (TSR), dynamic immersion test, uniaxial compression test, and indirect tensile strength test (IDT). The liquid anti-stripping agents used in the lab test were premixed with each asphalt binder (PG 64-22, PG 76-22) before being mixed with the aggregate. RESULTS :The result of the TSR test revealed that the effect of anti-stripping was highest when hydrated lime and liquid anti-stripping agent W were added. The correlation coefficient $R^2$ between the TSR result and cohesion ratio is 0.99, which indicates that the sensitivity of the TSR to moisture damage is reliable from the mechanical point of view. The covering ratio of the asphalt binder to the liquid anti-stripping agent W was determined to be higher than that to the other liquid anti-stripping agents. CONCLUSIONS :It is considered that the improved moisture resistance of asphalt mixture as a result of the use of anti-stripping agents can reduce the incidence of various pavement damages such as portholes caused by stripping, and the performance life of the asphalt road pavement can be prolonged.

• 대한토목학회논문집
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• 제38권2호
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• pp.319-325
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• 2018

최근 집중호우, 잦은 강설 등 이상기후에 따라 아스팔트 콘크리트 포장의 포트홀 발생이 급증하고 있다. 포트홀은 교통사고와 직결되는 파손형태로 인명피해, 차량 및 도로시설물 파손 등의 피해가 증가하는 추세이다. 이에 따라 포트홀 발생을 저감하기 위해 아스팔트 콘크리트 혼합물에 박리방지제를 의무적으로 사용하도록 권장하고 있는 실정이다. 국내에서는 비교적 사용이 편리하고 경제적인 소석회를 박리방지제로 주로 사용하고 있다. 본 연구에서는 순환 유동층 보일러 가동시 발생하는 보일러 부산 애쉬를 박리방지제로 활용하는 연구를 수행하였다. 연구결과 보일러 부산 애쉬를 아스팔트 콘크리트 혼합물 중량의 1~3% 혼합한 결과 TSR 기준을 모두 만족하였다. 품질변동을 감안하여 골재, 혼합물 등 다양한 조건의 보일러 부산 애쉬를 검토하였으며 실험결과 TSR 평균 0.87, 동적수침 후 피복률 60% 이상으로 안정적으로 품질기준을 만족하는 것으로 나타났다. 이에 따라 보일러 부산 애쉬는 안정적으로 박리방지제 성능을 발현하여 아스팔트 콘크리트 포장의 포트홀 발생 저감에 매우 효과적일 것으로 판단된다.

• 한국도로학회논문집
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• 제10권4호
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• pp.41-52
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• 2008

본 연구는 박리방지 첨가제를 혼입한 아스팔트 혼합물의 수분민감성에 대한 특성 평가 방안을 제시하고자, 기존의 수침 시험을 개선한 3가지 종류($H_c$, $V_s$, F-T)의 수침 방법을 통하여 생석회, 소석회, 1종의 액상 박리방지 첨가제를 혼입한 각 아스팔트 혼합물에 대한 수분민감성의 거동 특성을 분석하였다. 실험방법은 AASHTO TP-9에 규정된 간접인장시험(Indirect Tensile Test, IDT)을 통한 크리프시험 (Creep Test), 회복탄성계수시험(Resilient Modulus Test) 및 강도시험(Strength Test)을 수행하였다. 분석방법으로는 미국 플로리다 대학의 Roque에 의해 제안된 에너지비(Energy Ratio, ER) 개념을 사용하여 박리방지제의 사용에 따른 효과 및 수분민감도 특성을 평가하였다(Roque, 2004). 시험결과, 수분처리 방법 에 따른 아스팔트 흔합물의 물성 변화뿐만 아니라 박리 방지 첨가제에 따른 물성 변화가 현저하게 나타났다. 또한 누적 수분 손상에 의해 발생되는 균열에 대한 저항성이 각 첨가제 및 수분처리 방법에 따라 변화됨을 나타내었다. 이를 토대로 Energy Ratio를 분석한 결과 약 $10{\sim}30%$ 정도의 균열 저항성 변화가 나타났다.

• 한국도로학회논문집
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• 제17권1호
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• pp.77-82
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• 2015

PURPOSES : The purpose of this paper is to evaluate the moisture susceptibility of asphalt mixtures containing developed liquid anti-stripping agents using the boiling water test as a screening test. METHODS : The boiling water test was used to evaluate the moisture susceptibility of asphalt mixtures containing different anti-stripping agents. The tensile strength ratio was calculated to compare the moisture susceptibility of the asphalt mixtures after indirect strength tests were performed. Additionally, image analysis techniques were used to calculate and analyze the quantity of stripped area in the asphalt mixtures. RESULTS : In general, the asphalt mixtures containing anti-stripping agents showed a higher resistance of anti-stripping based on the boiling water test and tensile strength ratio. CONCLUSIONS : The boiling water test can be used to differentiate the resistance of moisture susceptibility of asphalt mixtures, except for asphalt mixtures containing hydrated lime. The boiling water test can be used as a screening test for asphalt mixtures before conducting time consuming and expensive indirect tensile strength tests.

• 한국도로학회:학술대회논문집
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• 한국도로학회 2005년도 춘계학술대회 논문집
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• pp.155-162
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• 2005

• 한국도로학회논문집
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• 제3권4호
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• pp.105-116
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• 2001

본 연구는 주물고사를 이용한 아스팔트 콘크리트와 주물고사의 물리적 화학적 특성을 비교 분석하는 것이다. 주물고사의 아스팔트 콘크리트 적용성을 평가하기 위하여 XRF, SEM, 제타전위를 측정하여 주물고사의 물리 화학적 특성을 알아보았다. 주물고사 아스팔트 콘크리트의 박리저항성을 향상시키기 위하여 박리방지제(소석회(Hydrated lime), 액상박리방지제)를 사용하였다. 그리고 주물고사 아스팔트 콘크리트 혼합물의 인장특성과 내구성 향상을 위하여 LDPE를 사용하였다. 또한 주물고사 아스팔트 콘크리트의 공용성을 알아보기 위하여 간접인장강도, 수분취약성시험, 동결 융해시험, 반복주행시험을 수행하였다. 시험결과 주물고사 아스팔트 콘크리트의 역학적 특성이 일반 아스팔트 콘크리트에 비해 같거나 향상되는 것으로 나타났다. 따라서 주물고사를 아스팔트 콘크리트에 재활용할 수 있다는 결론을 얻었다.

• 한국도로학회논문집
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• 제17권4호
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• pp.77-87
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• 2015

PURPOSES: It is theoretically well known all over the world, that porous hot mixed asphalt (HMA) with hydrated Lime improves moisture and rutting resistance, and reduces pothole occurrence frequency, as well as the life cycle cost (LCC). METHODS : Addictive in the two different formations of the liquid anti-stripping Agent and powder Hydrated-Lime was applied in this investigation in order to obtain relatively clear results according to their types and conditions. Firstly, the moisture conditions were set, and applied to the porous HMA mixtures with hydrated lime (anti-stripping agent). Next, it was followed by a non-destructive test with the application of three freeze-thaw cycles, which were individually carried out thrice to compare the results of the dynamic moduli. Lastly, the hydrated lime effect related to moisture sensibility to porous HMA has been verified through the analysis of the modulus results regarding the change rate of dynamic modulus per n-cycle. RESULTS: It is clear from this investigation, that the dynamic modulus is inversely proportional to the change in temperature, as the graph representing the rigidity of the thermorheologically simple (TRS) material showed gradual decline of the dynamic modulus with the increase in temperature. CONCLUSIONS: The porous HMA mixture with the anti-stripping agent (hydrated Lime) has been found to be more moisture resistant to freezing and thawing than the normal porous HMA mixture. It is clear that the hydrated lime helps the HMA mixture to improve its fatigue resistance.

• 한국도로학회논문집
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• 제19권2호
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• pp.87-95
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• 2017

PURPOSES : The objectives of this study are to evaluate moisture sensitivity of various asphalt mixtures and to suggest an alternate method for the dynamic immersion test, which is used to determine the application of anti-stripping agent, by analyzing bond strength. METHODS : The bond strength of various asphalt mixtures such as hot mix asphalt, warm mix asphalt, and polymer-modified asphalt was evaluated by the ABS test. In order to characterize moisture sensitivity at different temperatures of the mixtures, the ABS test was conducted at $-10^{\circ}C$, $5^{\circ}C$, $20^{\circ}C$, $40^{\circ}C$, and $54^{\circ}C$ under both dry and wet conditions. The concept of the bond strength ratio was applied for objective moisture sensitivity analysis. Moreover, the bond strength characteristic was compared to the dynamic immersion test to suggest an alternate method to determine the application of anti-stripping agent. RESULTS AND CONCLUSIONS : Overall, the polymer-modified asphalt demonstrates the highest bond strength characteristic regardless of moisture condition and temperature. The bond strength characteristic displays a highly reliable linear relationship from $5^{\circ}C$ to $40^{\circ}C$, and the relationship could be used to predict bond strength at any intermediate temperature. Based on the analysis of bond strength and retained asphalt ratio, the bond strength value of 1254 kPa could be applied as a criterion for anti-stripping agent.

• 한국도로학회논문집
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• 제18권6호
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• pp.123-130
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• 2016

OBJECTIVES : The objective of this research is to determine the moisture resistance of the freeze-thaw process occurring in low-noise porous pavement using either hydrated-lime or anti-freezing agent. Various additives were applied to low-noise porous asphalt, which is actively paved in South Korea, to overcome its disadvantages. Moreover, the optimum contents of hydrated-lime and anti-freezing agent and behavior properties of low-noise porous asphalt layer are determined using dynamic moduli via the freeze-thaw test. METHODS : The low-noise porous asphalt mixtures were made using gyratory compacters to investigate its properties with either hydrated-lime or anti-freezing agent. To determine the dynamic moduli of each mixture, impact resonance test was conducted. The applied standard for the freeze-thaw test of asphalt mixture is ASTM D 6857. The freeze-thaw and impact resonance tests were performed twice at each stage. The behavior properties were defined using finite element method, which was performed using the dynamic modulus data obtained from the freeze-thaw test and resonance frequencies obtained from non-destructive impact test. RESULTS : The results show that the coherence and strength of the low-noise porous asphalt mixture decreased continuously with the increase in the temperature of the mixture. The dynamic modulus of the normal low-noise porous asphalt mixture dramatically decreased after one cycle of freezing and thawing stages, which is more than that of other mixtures containing additives. The damage rate was higher when the freeze-thaw test was repeated. CONCLUSIONS : From the root mean squared error (RMSE) and mean percentage error (MPE) analyses, the addition rates of 1.5% hydrated-lime and 0.5% anti-freezing agent resulted in the strongest mixture having the highest moisture resistance compared to other specimens with each additive in 1 cycle freeze-thaw test. Moreover, the freeze-thaw resistance significantly improved when a hydrated-lime content of 0.5% was applied for the two cycles of the freeze-thaw test. Hence, the optimum contents of both hydrated-lime and anti-freezing agent are 0.5%.