• Magazine of RCR
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• v.5 no.3
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• pp.28-31
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• 2010

• International Journal of Highway Engineering
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• v.17 no.2
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• pp.21-30
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• 2015

PURPOSES : The purpose of this study was to evaluate the performance of rapid-setting polymer-modified asphalt mixtures with a high reclaimed asphalt pavement (RAP) content. METHODS: A literature review revealed that emulsified asphalt is actively used for cold-recycled pavement. First, two types of rapid-setting polymer-modified asphalt emulsion were prepared for application to high-RAP material with no virgin material content. The quick-setting polymer-modified asphalt mixtures using two types of rapid-setting polymer-modified asphalt emulsion were subjected to the following tests: 1) Marshall stability test, 2) water immersion stability test and 3) indirect tensile strength ratio test. RESULTS AND CONCLUSIONS : Additional re-calibration of the RAP was needed for laboratory verification because the results of analyzing RAP aggregates, which were collected from different job sites, did not deviate from the normal range. The Marshall stability of each type of binder under dry conditions was good. However, the Type B mixtures with bio-additives performed better in the water immersion stability test. Moreover, the overall results of the indirect tensile strength test of RAP mixtures with Type B emulsions exceeded 0.7. Further research, consisting of lab testing and on-site application, will be performed to verify the possibility of using RAP for minimizing the closing of roadways.

• International Journal of Highway Engineering
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• v.8 no.2 s.28
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• pp.23-30
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• 2006

Emulsified Asphalt Mixture(EAM) is more environmentally-friendly and cost-effective than typical Hot Mix Asphalt (HMA) because EAM does not produce carcinogenic substances, e.g., naphtha, kerosene, during the both of manufacturing and roadway construction process. Also, it does not require heating the aggregates and asphalt binder. However, EAM has some disadvantages. Generally EAM has a less load bearing capacity and more moisture susceptibility than conventional HMA. The study evaluated a Fiber modified EAM (FEAM) to increase load bearing capacity and to decrease moisture susceptibility of EAM. Modified Marshall mix design was developed to find Optimum Emulsion Contents (OEC), Optimum Water Contents (OWC), and Optimum Fiber Contents (OFC). A series of test were performed on the fabricated specimen with OBC, OWC, and OFC. Tests include Marshall Stability, Indirect Tensile Strength, and Resilient modulus test. Comparison analyses were performed among EAM, Fiber modified EAM (FEAM), and typical HMA to verify the applicability of EAM and FEAM in the field. Test results indicated that both of EAM and FEAM have an enough capability to resist medium traffic volume based on the Marshall mix design criteria. Also the study found that fiber modification is effective to increase the load bearing capacity and moisture damage resistance of EAM.

• 한국도로학회:학술대회논문집
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• 2009.11a
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• pp.545-548
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• 2009

• 한국방재학회:학술대회논문집
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• 2009.02b
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• pp.81.1-81.1
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• 2009

• Proceedings of the Korean Professional Engineer Association Conference
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• 1984.12a
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• pp.84-91
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• 1984

Heavy Residual Fuel oils is a mixture of reduced crude from crude unit, bottom products from vacuum and/or catalytic cracking unit with distillate to meet the specification and generally used as Heavy Fuel Oil for large combustion engines, boilers, etc…. But this study was made to investigate Heavy Residual Fuel oils for using as industrial raw material and resulted the following possibilties as valuable raw material as well as Heavy Fuel Oil. 1) Production of straight asphalt through vacuum distillation unit. 2) Using straight asphalt from vacuum distillation unit for manufacturing of Blown Asphalts, Cut Back Asphalts, Emulsified Asphalts and Asphalt Compound, etc…. 3) Using waxy oil side streams for manufacturing of raw oil to be Lube Oil base stocks through solvent dewaxing. 4) Production of lube base oils from dewaxed raw oil through chemical treatments. 5) Manufacturing of paraffine wax from slack wax to be produced as by product of dewaxing process.

• Elastomers and Composites
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• v.20 no.2
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• pp.115-131
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• 1985

Heavy residual fuel oils is a mixture of reduced crude from crude unit, bottom products from vacuum and/or catalytic cracking unit with distillate to meet the specification and generally used as heavy fuel oil for large combustion engines, boilers, etc$\cdots$. But this study was made to investigate heavy residual fuel oils for using as industrial raw material and resulted the following possiblities as valuable raw material as well as heavy fuel oil. 1) Production of straight asphalt through vacuum distillation unit. 2) Using straight asphalt from vacuum distillation unit for manufacturing of blown asphalts, cut back asphalts, emulsified asphalts and asphalt compound, rubber/asphalt sheet, etc$\cdots$. 3) Using waxy oil side streams for manufacturing of raw oil to be lube oil base stocks through solvent dewaxing. 4) Production of lube base oils and rubber process oils from dewaxed raw oil through chemical treatments. 5) Manufacturing of paraffine wax from slack wax to be produced as by product of dewaxing process.

• International Journal of Highway Engineering
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• v.7 no.4 s.26
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• pp.9-20
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• 2005

This study was carried out to select most efficient bonding methods of geogrid at the interface of old concrete pavement before placing asphalt overlay layer for reflection cracking retardation. Three bonding methods, a RSC-4 emulsified asphalt, a compound and an unsaturated polyester resin (UPR) were compared in this study. Three types of asphalt mixture (AC 60-80, RLDPE 8%, PG 76-22) and a dense-graded aggregate were used for overlay asphalt pavement. A reinforcing material which consists of a woven fabric underneath a glass fiber grid was used. An expedite test method which is for simulating mixed mode (mode I and II) fracture test was performed using a wheel tracker in laboratory. Cracking development by load repetition was measured as fatigue life (number of load cycle) and expansion of specimen body were measured for each test specimen. The results showed that UPR was the best and RSC-4 the next. But considering field applicability, RSC-4 was considered as an appropriate choice for bonding reinforcing material.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.1
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• pp.27-32
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• 2009

The main objective of this study is to develop a test for measuring the bond shear strength between pavement layers. The research is also conducted to evaluate tack coat materials and application rate in porous pavement. The experiment includes using two types of emulsions (RSC-4, Modified Emulsion) and a asphalt binder type (HM-1). HM-1 was developed to be applied in porous pavement. The bond shear strengths were measured by a direct shear type device under various test conditions. The shear strength may not be appropriate in the evaluation of the bond shear strength, while the toughness of the test may be useful. In case of the tack coat application rate in porous pavement, RSC-4 has to be used a minimum amount of $0.8l/m^2$ and modified emulsion asphalt has to be applied a volume of use $0.5{\sim}0.6l/m^2$. HM-1, asphalt cement type, is far stronger bond shear strength than emulsified asphalt tack coat and had showed the excellent trackless property.

• International Journal of Highway Engineering
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• v.13 no.2
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• pp.139-145
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• 2011

The practice of asphalt pavement recycling has grown rapidly over the decade, one of which is the cold in-place recycling with the foamed asphalt (CIR-foam) or the emulsified asphalt (CIR-emulsion). Particularly, in Iowa, the CIR has been widely used in rehabilitating the rural highways because it significantly increases the service life of the existing pavement. The CIR layer is typically overlaid by the hot mix asphalt (HMA) to protect it from water ingress and traffic load and obtain the required pavement structure and texture. Most public agencies have different curing requirements based on the number of curing days or the maximum moisture contents for the CIR before placing the overlay. The main objective of this study is to develop a moisture loss index that the public agency can use to monitor the moisture content of CIR layers in preparation for a timely placement of the wearing surface. First, the moisture contents were measured in the field using a portable time domain reflectometry (TDR) device. Second, the weather information in terms of rain fall, air temperature, humidity and wind speed was collected from the same location. Finally, a moisture loss index was developed as a function of initial moisture content, air temperature, humidity and wind speed. The developed moisture loss index based on the field measurements would help the public agency to determine an optimum timing of an overlay placement without continually measuring moisture conditions in the field.