• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.849-852
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• 2008

In the wheel tracking test to evaluate abrasion resistance for concrete surface coating materials applied parking lot, weight of the wheel, test temperature, scattered sand amount, wheel speed, etc. various test condition is used for reliable evaluating the abrasion resistance performance of surface coating materials and the results depends on the test condition. In this paper, we carried experimental study as following on abrasion resistance with 2kinds of different environmental conditions. - Commons : real car tire with 300kg of load, 5km/h of speed, 80,000 cycle. - Control A : no other deterioration condition - Control B : scattering 1.0g of sand per every 30rounds from 1m height.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2010.05a
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• pp.67-70
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• 2010

This study investigates the physical properties of the acrylic emulsion mortar according to variable composition set of redispersible emulsion powders. This materials have to be composed of many types of binders and chemical additives. So it is difficult to decide suitable mixing proportion of composition materials. The redispersible emulsion powders using "2, 4, 6, 8kg" of EVA polymers dispersion ranges are prepared with acrylic emulsion mortars and were tested for basic characteristics such as flexural, and compressive strength, wheel load. Through experiments we found that the improved formula to satisfy the standard of wheel load by EVA polymers, and the masration rangs between about 2.0% to 2.6% which the white portland cenmet and EVA polymers is good for resistauce wheel load.

• International Journal of Highway Engineering
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• v.7 no.3 s.25
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• pp.1-10
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• 2005

In this study, accelerated pavement tester(APT) was performed on long-life asphalt pavements that can save maintenance and user costs by increasing the design life twice longer than conventional asphalt pavements. Basic material testings are first conducted on a high modulus base(HMB) mixture developed in this study. Four different pavement sections including thin and thick conventional and thin and thick HMB courses are constructed to compare the load-carrying capacities and to investigate the fatigue and rutting performances using an accelerated pavement tester. Tensile strain values at the bottom of base courses under the various loading levels are measured. The tensile strain values of the HMB sections are lower than those of the conventional sections. It is observed from the APT performed on the thin pavement sections that no significant cracks are developed up to the 180,000 cycles of a wheel load. In terms of rutting, only 3mm of rutting is developed in the thick HMB section while 5.3mm of rutting is developed in the thick conventional section at the 90,000 cycles of the wheel load. The HMB material developed in this study can be successfully used in the long-life asphalt pavements because of its excellent fatigue and rutting performances. It is estimated from a series of structural analysis that the use of the HMB material instead of the conventional base materials may reduce the asphalt thickness at least 5cm because of its better load-carrying capacity.

• International Journal of Highway Engineering
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• v.4 no.1 s.11
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• pp.161-170
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• 2002

This study is a fundamental research for recycling waste polyethylene film(WPF) in asphalt concrete for roadway pavement. The objective of this study is to develop technology of making waste polyethylene asphalt mixture and evaluate properties of the asphalt concrete containing WPF. Asphalt concrete for surface course of pavement was produced through an appropriate mix-design using dense-graded and gap-graded aggregates. Marshall mix design, indirect tensile strength test, wheel tracking test and tensile fatigue test were performed. Test result showed that some WPF asphalt mixtures had a high tensile property and good resistances against rutting and fatigue cracking, compared with normal asphalt mixture.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.86-86
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• 2011

토목 기술의 발달로 장대교량이 증가함에 따라 교면 포장도 더 심각한 진동 및 충격, 기상조건에 노출되게 된다. 교면 포장은 차량의 주행의 편리성뿐 아니라 교량 구조물을 보호해야 하는 역할도 함께 수행하기 때문에 일반 토공부의 포장과 다른 성능을 필요로 한다. 교면 포장의 특수함을 감안하여 교면 포장의 품질을 평가하고, 설계와 적용시 반영 한다면 교량의 내구 연한 및 시공, 유지관리 비용을 절감 할 수 있을 것이다. 본 논문에서는 교면 포장에 요구되는 성능을 조사하고, 교면 포장 특히, 장대 교량 적용시 교면 포장의 성능 평가를 위한 평가 방법을 고찰하였다. 교면 포장의 가장 큰 구조적 특징은 교량의 진동과 휨에 의해 포장이 받게 되는 휨응력이다. 특히 교량의 장경간화에 따라 더 큰 진동과 변형을 경험하게 되는 교면 포장은 그에 따른 충분한 휨 추종성과 피로 저항성을 확보하여야 한다. 기존 토공부 포장에서는 실험이 간단한 원통형 공시체를 이용한 간접인장강도 모드의 실험으로 피로 성능을 평가하였으나, 교면 포장은 실제 거동 특성과 유사한 빔 피로 시험 모드가 보다 신뢰성이 높을 것으로 판단된다. 빔 피로시험 모드로는 3점, 4점, 5점 휨 피로 시험 모드가 있으며, 각각의 모드는 지지점의 개수, 재하점의 개수에 따라 다른 거동 특성을 평가 할 수 있다. 최근 개발된 5점 휨 시험의 경우 교량에서 발생하는 부(-)모멘트를 모사할 수 있어 보다 현실적인 검증이 가능할 것으로 예상된다. 이 외에도 실제 크기 모형을 이용하여 윤하중을 가하는 Full-scale 모델의 경우 비용과 시간이 많이 소요되는 단점이 있으나 가장 신뢰성이 높은 방법이라고 할 수 있다. 교면 포장은 교량구조부로 수분이 침투되는 것을 막아주는 역할을 하여야 하며, 특히 해상 교량의 경우의 염분과 겨울철 사용되는 제빙화학제는 콘크리트의 열화와 강구조물의 부식을 발생시키므로 교면 포장의 방수 성능 검토는 매우 중요한 역할을 한다. 일반 토공부 포장과 달리 교면 포장은 하부층이 대기에 노출되어 있기 때문에 겨울철에 더 낮은 온도로 포장체의 온도가 내려가게 되고, 온도가 떨어진 포장층은 스티프니스가 증감함에 따라 저온 균열의 발생확율이 높아지며, 휨추종성도 나빠질 가능성이 높다. 따라서 저온에서의 균열 저항성 및 스티프니스를 평가하는 것은 교면 포장 재료의 중요한 인자 중 하나이다. 포장과 포장 하부층의 접착은 포장층의 일체화된 거동을 할 수 있게 하기 때문에 내구성 향상에 중요하다. 특히 교량과 같이 진동과 변형이 많은 경우에 있어 포장 접착층의 성능은 포장과 교량 구조물의 파손에 더 큰 영향을 미치게 된다. 접착성능은 실내에서의 직접인장모드와 전단접착강도 시험 모드의 실험이 있으며, 현장에서 측정하는 Pull-off 실험 등이 있다. 최근에 교통량과 중차량의 증가와 더불어 교량이 장경간화 되어 가면서 평가방법과 기준을 과거보다 엄격하게 할 필요성이 있다. 하지만 현실은 교면포장에 대한 시방규정이 모호하기 때문에 본 논문에서 제시한 국내외의 다양한 평가방법을 통해 적절한 교면포장의 성능을 평가하고 교면포장의 거동특성에 대한 이해를 함으로써 보다 발전된 교량기술을 확보할 수 있을 것이다.

• International Journal of Highway Engineering
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• v.9 no.2 s.32
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• pp.51-62
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• 2007

Recently, the pavement distresses in the bridge deck have seriously affected the durability of bridge deck and driver's safety. The existing asphalt materials have the limitations in reducing the pavement distresses of brides deck. To protect the bridge deck and withstand the high deflection, it is necessary to develop the asphalt materials with good fatigue resistance for bridge deck pavement. The asphalt binder combined with SBS and two other admixtures has been developed for improving the resistance to fatigue cracking, productivity, and workability for bridge deck pavement. Based on the various binder test results, the developed binder is found to be PG 70-34 indicating very higher resistance against fatigue cracking. Fatigue testing, wheel tracking testing, and moisture susceptibility testing have been conducted to evaluate the performance of asphalt mixtures developed in this study. Laboratory test results show that the developed asphalt material has three times higher fatigue lives than the typical modified asphalt mixture. Full scale accelerated testing was also performed on the typical asphalt mixture and newly developed asphalt mixture to evaluate the full scale performance of asphalt mixtures. Test results indicate that the length of cracking on the new materials is only 38% of the typical material at the 250,000 load repetitions.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.4
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• pp.523-530
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• 2019

Pavement distress and traffic accidents are caused by pot-hole. In addition, direct and indirect damages of road users are increasing, such as loss of life due to personal injury and damage to vehicles. Generally, the asphalt concrete pavements are continuously aging from the production process to the terminal performance period. Aging causes stripping due to cracks and moisture penetration and weakening the pavement structure to induce pot-hole. In this study, adhesion performance and moisture sensitivity were evaluated according to aging degree in order to investigate the effect of aging on asphalt pavement. As a result of the study, the viscosity of the asphalt binder was increased with aging and the bond strength of the aged was increased 2~3 times than that of the unaged. The results of accelerated aging test showed an increases in indirect tensile strength and the increase in the TSR (Tensile Strength Ratio) by 4.2~8.9 %. As a result, it is noted that the anti-stripping and adhesion performances of the aged asphalt concrete are improved compared to the unaged one under the aging conditions of asphalt binder coated on aggregates.

• International Journal of Highway Engineering
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• v.1 no.1
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• pp.97-106
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• 1999

This study was conducted to develop a test system for evaluating resistance against reflection cracking in shear mode caused by wheel load in asphalt concrete overlaid on the deteriorated cement concrete pavement. Reflection cracking resistance of selected polymer modified asphalt(PMA) mixtures with and without reinforcement was evaluated using this test system. It was shown that the test results accounted for the effectiveness of materials and reinforcement characteristics in terms of the difference in the resistance against reflection cracking. A shear failure life of a certain mixture was estimated with a high coefficient of determination. when the test results were used in a well known prediction model. Therefore, it seemed to be possible to use this technique for predicting a relative service life of on overlay.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.2
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• pp.311-317
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• 2018

The new asphalt surface reinforcement method (ASRM) is one of the preventive maintenance methods in asphalt concrete pavements. The adhesion performance of new ASRM satisfied the standard of non-slip pavement and bridge waterproofing materials. As a results of durability tests (as wheel load, rolling bottle and UV resistance test), the new ASRM showed sufficient resistance to traffic and environmental loads. The waterproof and chemical resistance tests of new ASRM were conducted to evaluate whether the pavement could be protected from water and chemicals and the performances of new ASRM were satisfactory. Furthermore, the new ASRM demonstrated some rejuvenation effects due to its toughness increases in recycled asphalt concrete mixture by 5% compared to the conventional hot mix asphalt mixture using reclaimed asphalt pavement. In conclusion, the new ASRM was evaluated to protect the asphalt concrete pavement and increase the lifetime.

• International Journal of Highway Engineering
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• v.11 no.3
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• pp.97-109
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• 2009

One of the main causes of asphalt rutting is high temperature of the pavement. Nevertheless, there has been few research on lowering the pavement temperature for reducing rutting. This study investigated the performance characteristics of moisture-retaining porous asphalt pavement, which is known to have a temperature reducing effect. The purpose of this study is to quantify the temperature reducing effect of moisture-retaining porous asphalt pavement and its effect of reducing rutting through Accelerated Pavement Testing(APT). Additionally, the possibility of reducing the thickness of the pavement in comparison to general dense grade pavement by analyzing structural layer coefficient of moisture retaining pavement. A total of three test sections consisting of two moisture-retaining porous asphalt pavement sections and one general dense-grade porous asphalt pavement section were constructed for this study. Heating and spraying of water were carried out in a regular cycle. The loading condition was 8.2 ton of wheel load, the tire pressure of $7.03kgf/cm^2$, and the contact area of $610cm^2$. The result of this experiment revealed that the temperature reducing effect of the pavement was about $6.6{\sim}7.9^{\circ}C$(average of $7.4^{\circ}C$) for the middle layer and $7.9{\sim}9.8^{\circ}C$(average of $8.8^{\circ}C$) for surface course, resulting in a rutting reduction of 26% at the pavement surface. Additionally, the structural layer coefficient of moisture retaining pavement measured from a laboratory test was 0.173, about 1.2 times that of general dense grade pavement. The general dense-grade porous asphalt pavement test section exhibited rutting at all layers of surface course, middle layer, and base layer, while the test sections of moisture-retaining porous asphalt pavement manifested rutting mostly at surface course only.