• Magazine of the Korean Society of Agricultural Engineers
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• v.41 no.5
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• pp.104-105
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• 1999

This study was performend to examine Poisson's ration of polymer-modified asphalt concrete due to temperature variatino . Asphalt binder used in this study was an AC85-100, penetration grade of 85-100, and polymer for modifying asphalt were domestic LDPE(Low-density polyethylene) and SBS(Styrene-butadiene-styrene). Aggregate was a crushed gneiss which was most widely used in the middle part of Korea. Using these materias, asphalt mixture slab(340mm$\times$240mm$\times$80mm) with optimum asphalt content from mix design was made and cut into square pillar (80mm$\times$80mm$\times$160mm). Poisson's ration was measured in various temperture (-15$^{\circ}C$, -1$0^{\circ}C$, -5$^{\circ}C$,$0^{\circ}C$,5$^{\circ}C$,1$0^{\circ}C$ and 2$0^{\circ}C$) under the load of one axis repeated compression mode. Poisson's ration of normal asphalt polymer modified asphalt mixtures in normal temperatures. This indicated that AP mixture was more susceptible to temperature effects. From regression aalysis of experimental results, the difference of Poisson's ration between normal and low temperature showed that polymer modified asphalt mixture were lower than AP mixture except for SBS modified asplat mixture.

• Journal of the Society of Disaster Information
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• v.16 no.3
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• pp.602-610
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• 2020

Purpose: This paper aims to develop an asphalt pavement system with reduced cracks, structural stability and waterproofing at sub-zero temperature conditions. Method: Under various temperature conditions, SIS polymer asphalt, normal asphalt, and guss asphalt were tested for adhesion strength of the binder and deformation strength of the mixture. Result: The adhesion strength of asphalt binder was higher in SIS polymer asphalt than that of normal asphalt and guss asphalt. The deformation strength of the asphalt mixture was almost the same as that of SIS polymer asphalt and normal asphalt. The energy absorption of the SIS polymer asphalt mixture was relatively higher than that of the normal asphalt mixture and the guss asphalt mixture. Conclusion: The maximum load of the SIS polymer asphalt mixture was lower than that of the guss asphalt mixture. However, in sub-zero temperature conditions, sufficient energy absorption was secured by stable load reduction. Therefore, it is expected to improve the durability of asphalt pavement by reducing the occurrence of microcracks with stable fracture behavior.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.4
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• pp.611-619
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• 2018

Basalt powder sludge (abbreviated BPS) is an inevitable industry by product resulted from the stone processing. Recently, demands for natural materials have been increasing in the construction and landscaping fields, therefore, amounts of BPS have been also increasing. Since most of BPS are used as landfill and earth soil, it is necessary to figure out to expedite their utilization. In this study, by considering the characteristics of precipitation of Jeju, effectiveness of BPS as a filler for asphalt compounds mixed with cement were analyzed. As a result, BPS satisfies quality criterion required in KS F 3501. Marshall mixing designs were performed to determine the optimal asphalt content for the Modified recycling asphalt mixture (27% recycling aggregate) and the Normal asphalt mixture. Effectiveness of BPS were identified by the Marshall Stability Test with the mixing ratio (level 3) of two asphalt compounds and composition ration (level 3) of BPS and cement. Performance of asphalt compounds shown appropriate effect of mixing and composition ratios of the filler were assessed. Test results show that two types of asphalt compounds satisfy the quality standards of the MLIT (2015). Therefore, BPS could be used as filler for asphalt compounds.

• Journal of The Korean Society of Agricultural Engineers
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• v.61 no.3
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• pp.31-41
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• 2019

More than 90% of roadway in the world are paved as asphalt concrete pavement due to its excellent properties compared with other paving materials; excellent riding quality, flexibility, anti-icing property and easy maintenance-ability. In this study, to make best use of the softer property of the asphalt mixture, the flexible sand asphalt mixture (FSAM) was developed for pedestrian ways. The mix design was conducted to prepare FSAM using PG64-22 asphalt, screenings (sand) less than 5mm, crumb rubber, hydrated lime and limestone powder without coarse aggregate. The deformation strength ($S_D$), indirect tensile strength (ITS) and tensile strength ratio (TSR) tests were conducted to make sure durability of FSAM performance. The impact energy absorption and flexibility were measured by drop-boll test and the resilient modulus ($M_R$) test. The impact energy absorption of FSAM was compared with normal asphalt pavement, concrete pavement, stone and concrete block for pedestrian way. As a result of drop-boll test, FSAM showed higher impact energy absorption compared with other paving materials with the range of 18% to 43%. Impact energy absorption of FSAM increased with increasing test temperature from 5 to $40^{\circ}C$. The results of $M_R$ test at $5^{\circ}C$ showed that the flexibility of FSPA was increased further, because the $M_R$ value of the sand asphalt was measured to be 38% lower than normal dense-graded asphalt mixture (WC-1). Therefore, it was concluded that the FSAM could provide a high impact absorbing characteristics, which would improve walking quality of the pedestrian ways.

• 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.

• International Journal of Highway Engineering
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• v.18 no.3
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• pp.1-9
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• 2016

PURPOSES : This study aims to show the difference of the binder aging level in the hot-mix asphalt (HMA) mixture after short-term aging (SA) under different aging conditions, such as mixture temperature and duration in hour. METHODS : Three SA times (i.e., 1 h, 2 h, and 4 h) at two temperatures (i.e., $160^{\circ}C$ and $180^{\circ}C$) were used for the normal mixtures prepared using a PG64-22 asphalt. The field long-term aging (LA) was simulated by applying the same LA procedure (65 h at $110^{\circ}C$) to all compacted specimens, prepared at the air void of 7% using each SA-treated mixture, in a convection oven. The binder aging level was measured in terms of large molecular size by gel-permeation chromatography (GPC) from the mixture and the absolute viscosity (AV) from the recovered binder. The aging levels were evaluated using those two properties after SA and LA, and then compared based on the normal SA (NSA) mixture (1 h at $160^{\circ}C$). The service life reduction caused by SA in various conditions was estimated based on the aging level of the field cores from different locations in various service lives. RESULTS : The results of the laboratory evaluation indicated that the binder of the mixture, which was treated at longer SA time and higher temperature, showed a significantly higher aging level than the NSA mixture. The binder aging level from a longer time, such as 2 h and 4 h SA, or at a higher temperature ($180^{\circ}C$), were estimated to be similar to that of the mixtures, which had already been in field service for several years. CONCLUSIONS : The HMA mixture should be produced at a moderate temperature, such as $160^{\circ}C$, and placed within a limited hauling and queuing time to avoid a significant short-term aging of the binder before placement in the field pavement. The SA for a longer time at a higher temperature than the NSA condition was found to be detrimental to the service life of the asphalt pavement.

• International Journal of Highway Engineering
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• v.3 no.1 s.7
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• pp.185-197
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• 2001

This paper dealt with modification of effective crack length model (ECM) by adding Poisson's ratio term to evaluate fracture toughness of asphalt concrete which varies its material property by temperature. The original ECM model was developed for solid materials, such as cement concrete, and Poisson's ratio of materials was not considered. However, since asphalt concrete is sensitive to temperature variation and changes its Poisson's ratio by temperature, it should be taken into consideration to know exact fracture property under various temperatures. Four binders, including 3 polymer-modified asphalt (PMA) binders, were used to make a dense-grade asphalt mixture and 3-point bending test was peformed on notched beam at low temperatures, from -5oC to 35oC. Elastic modulus, flexural strength and fracture toughness were obtained from the test. The results showed that, since Poisson's ratio was considered, the more accurate test values could be obtained using modified ECM equation than original ECM. PMA mixture showed higher stiffness and fracture toughness than normal asphalt mixture under very low temperatures.

• International Journal of Highway Engineering
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• v.18 no.6
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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%.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.2 no.2
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• pp.11-18
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• 1982

The binder for hot mix type colored pavement must have the same physical qualities as the straight asphalt cement, but its color must not be dark-brown. We developed a kind of synthetic resin binder with light yellow color and confirmed its possibility as a binder for colored pavement through the several comparison tests between the straight asphalt cement concrete mixture and the mixture of binder and aggregate for colored pavement. For the pigment, it has been assured through tests that home products have the possiblities to be used. The binder has come to the stage of practical use through the trial mixing by asphalt mixing plant and the trial field placing. The mixing operation and the paving method of colored mixture are same as normal asphalt concrete mixture, but the quantity of pigment replaces that of mineral filler. The required content of pigment is decided by the trial mixing with other materials to be used.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.3
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• pp.947-954
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• 2014

In general, Fracture of the material is not occurring of the maximum normal stress or the maximum shear stress failure in the state. Maximum normal stress and maximum shear stress in the state of Critical coupling from being destroyed based on the Mohr-Coulomb theory. Couple of different mixtures, including permeable asphalt pavement, SMA and dense-graded asphalt mixture, were used for compression triaxial test at $45^{\circ}C$ and $60^{\circ}C$. Mohr-Coulomb theory to the analysis of compression triaxial test result of the internal friction angle $38.9^{\circ}{\sim}46.9^{\circ}$ measured somewhat irregularly, but in the case of cohesion, depending on whether the temperature and immersion of the specimen appeared differently. In addition, Indirect tensile test and compression triaxial test of the asphalt mixture to determine the correlation between compression triaxial test results assessed as cohesion and internal friction angle calculated using the theoretical Indirect tensile strength and measured indirectly tensile strength were analyzed. The Measured & Predicted IDT St values tended to be proportional.