• International Journal of Highway Engineering
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• v.4 no.3 s.13
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• pp.43-49
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• 2002

Asphalt pavements have to perform under the conditions of heavily-loaded vehicles due to the industrialization and large temperature variance between the summer and the winter. Due to these factors, a characteristics change of early permanent deformation becomes a big issue, and to remedy this problem many research to use modified asphalt are being widely conducted. However, most of the modified asphalt is being paved after milling the surface course and applying tackcoating, and it is being used mostly for the repair and maintenance purpose rather than pavement of new national road. The purpose of this investigation is to obtain some fundamental data for the evaluation of the performance and long-term performance of the construction material mixtures by the laboratory test and field experiments. For the field experiment, 200m of two-lanes national road, that is being paved for the new national road under the direction of Pusan Regional Construction Management Office, was paved with SBS PMA and PSMA asphalt mixtures, which are an modified asphalt mixtures used for the surface course, on top of the base course paved with other modified asphalt mixtures. The remaining section of the new national road was paved with dense grade mixture. The laboratory tests assessed and analyzed the mixture characteristics by Marshall's stability test, strength tests and wheel-tracking test. On the basis of the evaluation result of the temperature control and roughness of the newly constructed road at the field experiment site, it is desired to evaluate and identify the most economic modified asphalt mixtures by long-term performance evaluation and LCC(Life Cycle Cost) analysis in order to apply the test result to the design of new road construction in the future.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.4
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• pp.489-495
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• 2016

In this study, the Warm-Mix Asphalt was prepared using a modified Sulfur Binder mixed with an additive of a polymer component in sulfur, which is an industrial by-product generated in the crude oil refining process. The dynamic stability and durability characteristics of the prepared Warm-Mix Asphalt was evaluated by the indirect tensile strength, the tensile strength ratio before and after water immersion and freezing-thawing, and the dynamic stability by wheel tracking test. The Warm-Mix Asphalt Mixtures using Modified Sulfur Binder has a tensile strength ratio before and after water immersion of 0.88, which is about 1.13 times that of the Warm-Mix formed modified Asphalt, and the tensile strength ration before and after freezing-thawing is also 0.82, thus, all tensile strength ratios satisfied the KS quality standard value of 0.75 or more. The indirect tensile strength was 1.6MPa which was twice the KS quality standard value of 0.8MPa, and about 1.24 times higher than that of normal heated asphalt 1.29MPa. In addition, the dynamic stability by the wheel tracking test was 14,075 times/mm, which was about 15 times higher than that of normal heated asphalt and about 3 times higher than that of the Warm-Mix formed modified Asphalt, showing excellent resistance to plastic deformation such as fatigue cracks.

• International Journal of Highway Engineering
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• v.6 no.3 s.21
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• pp.79-90
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• 2004

Rutting on asphalt pavement surface is an important damage in most roadways in the world. Most of researches have developed prediction model for rutting on asphalt pavement as a function of physical properties of asphalt binder. But this study was devised to estimate rutting based on fundamental properties of asphalt mixture, not binder. Therefore this study objective is to estimate rutting based on volumetric properties, that is Air void, Void in mineral aggregate(VMA) and Void filled with asphalt(VFA), of asphalt mixture with various asphalt binders, aggregates and aggregate gradation. Results showed that it was possible to estimate rutting depth based on volumetric variables of asphalt mixture. In addition, VMA, the variable which is nor used In mix design in Korea, showed a significant correlation with rutting, It is recommended that VMA is adapted as a variable in domestic mix design. Also, It showed that VFA in the specification should be lowered at least 5% point since VFA was somewhat higher than optimum.

• Journal of the Korea institute for structural maintenance and inspection
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• v.28 no.3
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• pp.59-65
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• 2024

In this study, in order to improve the mechanical properties and durability of asphalt mixtures, a modifier (CSM, Cationized Silicate Modifier) was applied to asphalt to derive optimal mixing ratio conditions. Design of asphalt mixture using modified asphalt binder was conducted, and moisture resistance and dynamic stability were evaluated for optimal mixing conditions. The evaluation results showed that it exceeded the standards stipulated in the relevant guidelines, and as a result of conducting a water permeability test on the optimal mixing condition, it was confirmed that impermeable performance was secured. As a result of examining the noise reduction performance through field test, a noise reduction performance of about 10 dB was secured compared to before paving. It will be necessary to secure reliability through continuous noise generation evaluation in the future.

• 한국도로학회지:도로
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• v.2 no.4 s.6
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• pp.37-49
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• 2000

이 보고서는 수퍼페이브의 개념으로 설계된 혼합물이 시방규정에 만족하기 위하여 꼭 필요한 혼합물의 생산, 포설 및 다짐에 대한 내용을 정리한 것이다. 이 보고서 단독으로는 큰 의미가 없으며, 기존의 일반적인 혼합물에 사용되었던 훌륭한 시공기술이 동시에 사용되어야한다. 수퍼페이브가 적용됨으로 해서 발생되는 혼합물의 가장 큰 변화는 굵은입도의 혼합물사용 및 보다 많은 양의 모난골재사용 그리고 개질아스팔트의 사용 등이다. 이러한 변화들은 약간의 시공순서의 수정을 필요로 하게 된다. 이 보고서는 이러한 것에 대한 몇 가지 제안을 포함하고 있다.

• International Journal of Highway Engineering
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• v.13 no.2
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• pp.41-48
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• 2011

Warm-mix asphalt(WMA) technology has been developed to allow asphalt mixtures to be produced and compacted at a significantly lower temperature. The WMA technology was identified as one of means to lower emissions for $CO_2$ and has been spread so quickly in the world. Recently, two innovative WMA additives has been developed to reduce mixing and paving temperatures applied in asphalt paving process in Korea. Since the first public demonstration project in 2008, many WMA projects have successfully been constructed in national highways. In 2010, the WMA field trial was conducted on new national highway construction under Dae-Jeon Regional Construction Management Administration. The two different WMA loose mixtures(WMA and WMA-P) and a HMA mixture were collected at the asphalt plant to evaluate their mechanical performance in the laboratory. The Third-scale Model Mobile Loading Simulator(MMLS3) was adopted to evaluate rutting resistance and moisture damage under different traffic and environmental conditions. In this study, plant-produced WMA mixtures using two WMA additives along with the conventional hot mix asphalt(HMA) mixtures were evaluated with respect to their rutting resistance and moisture susceptibility using MMLS3. Based on the limited laboratory test results, plant-produced WMA mixtures are superior to HMA mixtures in rutting resistance and the moisture susceptibility. The WMA additive was effective for producing and compacting the mixture at $30^{\circ}C$ lower than the temperature for the HMA mixture.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.146-152
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• 2018

In this study, to improve the performance of asphalt mixtures for plastic deformation occurring mainly in Korea, complex modifiers were prepared by mixing powders and liquid type modifiers. The main constituents were powdery diatomaceous earth, mica and carbon black, and liquid type solid 70% SBR latex. The tensile strength ratios for the two asphalt mixtures used in the test were above 0.80 for the Ministry of Land Transportation (2017) asphalt mixture production and construction guidelines. The effects of increasing the tensile strength in the dry state was more than 14% when the composite modifier was added. The deformation rate per minute by the wheel tracking test load was an average of 0.07 to 0.147 for each mixture. The strain rate per minute was improved by the modifier, and the dynamic stability was improved by almost 100% from 295 to 590. In addition, the final settling was reduced from 11.38 mm to 9.57 mm. A plastic deformation test using the triaxial compression test showed that the amount of deformation entering the plastic deformation failure zone at the end of the second stage section and in the third stage plastic deformation section was 1.76 mm for the conventional mixture and 1.50 mm for the complex modifier mixture. The average slope of the complex modifier asphalt mixture mixed with the multi-functional modifier was 0.005 mm/sec. The plastic deformation rate is relatively small in the section where the road pavement exhibits stable common performance, i.e. the traffic load.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.2 no.2
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• pp.65-71
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• 2001

Recently the quantities of waste asphalt concrete at construction sites have increased greatly, but the maintenance and final disposal is very difficult problem. Therefore, we were faced with a worsening environmental problem brought about illegal measures. One of the most effective recycling method is cold recycling. This method will satisfy treatment and recycling of construction wastes. Also it is very important question in the preservation of environmental and natural resources. So, in this paper, we dealt cold recycling modified asphalt mixtures using emulsified asphalt to concern the effect of adding reclaimed asphalt concrete 30, 40, 50% and using SBR Latex for modified asphalt mixtures.

• International Journal of Highway Engineering
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• v.7 no.2 s.24
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• pp.1-12
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• 2005

This study was conducted to evaluate effect of geogrid and fabric, which are used underneath the overlaid asphalt pavement for retarding reflection cracking by simulated laboratory test. In this study, an interlayer at the interface between old concrete pavement surface and overlaid asphalt mixture, and polymer-modifier were used as an effort of retarding reflection crack initiation and for strengthening mixture. Five products were used in preparation of asphalt concrete beam specimen which was tack coated on top of jointed concrete block. Simulated Mode I and II fracture test were conducted under wheel loading and results were compared among those products. From the test results, several material and reinforcement combinations were observed to have a significant retardation effect against reflection cracking. The most effectively strengthened pavement against reflection cracking was found to be the LDPE-modifier asphalt mixture with a grid reinforcement at the bottom.

• 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.