• International Journal of Highway Engineering
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• v.8 no.1 s.27
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• pp.45-54
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• 2006

The Construction policy of government ever since 1970s have brought the economical growth, but has been causing environmental problems. Most roads were paved either asphalt concrete or portland cement concrete. These types of pavements has caused to rise temperature by making local heat islands in urban during summer time. Recently the wet-mixing solidified soil pavement, a kind of soil-cement, has developed and has been applied to the environment-oriented pavement. The solidified soil wet-mixed is placed on the subgrade along with asphalt concrete and portland cement concrete. Thermistors are laid in these field test pavements. The temperature gradients of these pavements are automatically measured with time. As the results of this test, the equation estimating surface temperature of pavement is proposed by analyzing measured temperature data. It is shown that the temperature change within the surface layer due to the change of air temperature is the greatest in the asphalt mixture and the least in the solidified soil mixture. Since it is proven that this wet-mixing solidified soil pavement emit less radiant heat than other existed pavements. Therefore this type of pavement can be successfully applied to the roads, such as walks, parkways, and bikeways, which are required to be human-friendly and environment-oriented.

• Environmental Engineering Research
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• v.25 no.1
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• pp.52-61
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• 2020

The article examines the impact differences between producing concrete and asphalt. Both materials are widely used in the construction industry. Construction activities account for a large portion of greenhouse gases. Therefore, it is important to consider the Life Cycle Analysis (LCA) to reduce environmental impacts. In this study, the material processes were inputted into an LCA program called SimaPro. The database used for the study was Ecoinvent as it is one of the major databases within SimaPro. The materials were compared against impacts per kg of material produced as the functional unit. Each process was created using the materials, energy and transportation required to produce the materials. Waste streams were also included in the process to determine the impacts after the product was done with its useful life. Using the ReCiPe method, an LCA was conducted. Midpoint and endpoint categories were examined for both the productions. The processes had similar results for the human health and ecosystems categories; however asphalt was marginally higher for both. Asphalt had exceeded concrete in the resource impact category by 100 mPt. The results indicate that concrete is the more sustainable building material. Determination of various impacts of the materials is important for material selection.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.3 no.1
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• pp.43-51
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• 1983

The fatigue failure envelopes for the prediction of the fatigue life of asphalt pavements were obtained from the results of laboratory fatigue test for asphalt mixture. The envelopes did not depend on the experimental temperature and the number of loading, and varied with the types of asphalts. In the case of dense graded asphalt concrete, the envelopes formed a single curve regardless of the penetration of the asphalt. On the other hand, the method for the fatigue life prediction was presented based on the envelopes obtained and the triple layered elastic theory developed by Burmister.

• International Journal of Highway Engineering
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• v.19 no.2
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• pp.1-6
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• 2017

PURPOSES : Pavement textures can be categorized into four according to wavelength: microtexture, macrotexture, megatexture (roads), and roughness. Pavement surface texture influences a number of aspects of tire-pavement interaction such as wet-weather friction, tire-pavement noise, splash, spray, tire-wear, and rolling resistance. In particular, macrotexture is the pavement surface characteristic that considerably impacts tire-pavement noise. In general, it can be demonstrated that tire-pavement noise increases with the increase of texture depth and wavelength. Recently, mean profile depth (MPD) and wavelength have been used to evaluate tire-pavement noise. This study aimed to identify the relationship between mean profile depth and average wavelength for asphalt pavement based on the information obtained on a number of asphalt pavement sections. METHODS : Profile data were collected from a number of expressway sections in Korea. In addition, mean profile depth and average wavelength were calculated by using this profile data. Statistical analysis was performed to determine the correlationship between mean profile depth and average wavelength. RESULTS:This study demonstrates a linear relationship between mean profile depth and average wavelength for asphalt concrete pavement. CONCLUSIONS :The strong relationship between mean profile depth and average wavelength of asphalt pavement was determined in this study.

• Journal of the Korean Geosynthetics Society
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• v.1 no.1
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• pp.53-61
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• 2002

Even though a lot of laboratory and field tests for asphalt pavements using geosynthetics have been conducted recently, any rational and systematic analysis for the economic efficiency of the asphalt pavement systems reinforced by using geosynthetics has not been proposed yet. In this study, the economic analysis considering the traffic characteristics for the glass fiber sheet reinforced asphalt pavement was performed using the Life Cycle Cost Analysis(LCCA) which is commonly used for the economic analysis technique. The economic efficiency for the glass fiber sheet reinforcement and the traffic characteristics was examined by applying the test results from the literature review to the economic analysis model.

• 한국도로학회:학술대회논문집
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• 2008.10a
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• pp.93-102
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• 2008

An energy based crack growth model is developed in this study to simulate the propagation of top-down cracking in asphalt pavements. A viscoelastic fracture mechanics approach, generalized J integral, is employed to model the crack growth of asphalt concrete. Laboratory fatigue crack propagation tests for three different asphalt mixtures are performed at various load levels, frequencies and temperatures. Disk-shaped specimens with a proper loading fixture and crack growth monitoring system are selected for the tests. It is observed from the tests that the crack propagation model based on the generalized J integral is independent of load levels and frequencies, while the traditional Paris' law model based on stress intensity factor is dependent of loading frequencies. However, both models are unable to take care of the temperature dependence of the mixtures. The fatigue crack propagation model proposed in this study has a good agreement between experimental and predicted crack growth lives, which implies that the energy based J integral could be a better parameter to describe fatigue crack propagation of viscoelastic materials such as asphalt mixtures.

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.357-360
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• 2007

Water retaining pavement is a pavement to lower the surface temperature by using evaporation of the water that the pavement contains when the pavement is heated by the sun in the daytime. The objective of this study is to develop water retaining materials. In this study we evaluated the practical application of a sepiolite and a charcoal as a water retaining material. We produced dense grade asphalt pavement, porous asphalt pavement, semi-rigid Pavement, semi-rigid pavement included a charcoal and semi-rigid pavement included a sepiolite, and then tested surface temperature characteristics. The test result says that water retaining pavements using a sepiolite and a charcoal lower surface temperature more than $10^{\circ}C$ compared to dense grade asphalt pavement. We confirm the practical application of a sepiolite and a charcoal as a water retaining material according to the test results.

• International Journal of Highway Engineering
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• v.10 no.1
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• pp.75-85
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• 2008

Moisture damage of asphalt mixtures can occur because of a loss of bond between the asphalt binder and the fine and coarse aggregates. Therefore, moisture damage on asphalt pavements is the main cause of potholes, which is one of the main distress type of asphalt pavement. The purpose of this study is to evaluation effect moisture damage on material properties of asphalt mixtures through the laboratory performance test. The existing Modified Lottman test procedure was improved and the number of times that thermal cyclic conditioning can be added until the asphalt mixtures is damaged, was tested in order to exhibit the changes of the material properties because of moisture damage by immersion. Through the above experiments, it was found that the material properties of asphalt mixtures on room-temperature were rapidly decreased with loss of about 50% at initial stage of moisture damage caused by the amount of repeated immersion. Also, it was found that the property damage ratio using material properties of failure energy and $DCSE_f$ by test temperature $25^{\circ}C$ were showed a high relationship to moisture damage of the asphalt mixtures caused by the amount of repeated immersion.

• International Journal of Highway Engineering
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• v.19 no.3
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• pp.31-43
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• 2017

PURPOSES : The objective of this study is to verify the effect of fiber grid reinforcement on the long-term performance of asphalt pavement overlaid on old concrete pavement by performing field investigation, laboratory test, and finite element analysis. METHODS : The reflection cracking, roughness, and rutting of fiber grid reinforced overlay sections and ordinary overlay sections were compared. Cores were obtained from both the fiber grid reinforced and ordinary sections to measure bonding shear strength between the asphalt intermediate and asphalt overlay layers. Fracture energy, displacement after yield, shear stiffnesses of the cores were also obtained by analyzing the test results. Finite element analysis was performed using the test results to validate the effect of the fiber grid reinforcement on long-term performance of asphalt pavement overlaid on the old concrete pavement. The fatigue cracking and reflection-cracking were predicted for three cases: 1) fiber grid was not used; 2) glass fiber grid was used; 3) carbon fiber grid was used. RESULTS : The reflection-cracking ratio of fiber grid reinforced sections was much smaller than that of ordinary sections. The fiber grid reinforcement also showed reduction effect on rutting while that on roughness was not clear. The reflection-cracking was not affected by traffic volume but by slab deformation and joint movement caused by temperature variation. The bonding shear strength of the fiber grid reinforced sections was larger than that of the ordinary sections. The fracture energy, displacement after yield, and shear stiffnesses of the cores of the fiber grid reinforced sections were also larger than those of the ordinary sections. Finite element analysis results showed that fatigue cracking of glass or carbon fiber grid reinforced pavement was much smaller than that of ordinary pavement. Carbon fiber grid reinforcement showed larger effect in elongating the fatigue life of the ordinary overlay pavement compared to glass fiber grid reinforcement. The binder type of the overlay layer also affected the fatigue life. The fiber grid reinforcement resisted reflection-cracking and the carbon fiber grid showed the greater effect. CONCLUSIONS :The results of field investigation, laboratory test, and finite element analysis showed that the fiber grid reinforcement had a better effect on improving long-term performance of asphalt pavement overlaid on the old concrete pavement.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5D
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• pp.831-838
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• 2006

An experimental/analytic study has been conducted to understand the adverse effects of low vehicle speed, high axle load and high tire pressure on the performance of asphalt pavements. Of 33 asphalt sections at KHC test road, two sections having different base layer thickness (180 mm versus 280 mm) are adopted for rollover tests. During the test, a standard three-axle dump truck maintains a steady state condition as moving along the wheel path of a passing lane, and lateral offsets and real travel speed are measured with a laser-based wandering system. Test results suggest that vehicle speed affects both longitudinal and transverse strains at the bottom of asphalt layer (290 mm and 390 mm below the surface), and even slightly influences the measured vertical stresses at the top of subbase and subgrade due to the dynamic effect of rolling vehicle. Since the anisotropic nature of asphalt-aggregate mixtures, the difference between longitudinal and transverse strains appears prominent throughout the measurements. As the thickness of asphalt pavement increases, the measured lateral strains become larger than its corresponding longitudinal strains. Over the limited testing conditions, it is concluded that higher axle weight and higher tire pressures induce more strains and vertical stresses, leading to a premature deterioration of pavements. Finally, a layered elastic analysis overestimates the maximum strains measured under the 1st axle load, while underestimating the maximum vertical stress in both pavement sections.