• International Journal of Highway Engineering
• /
• v.13 no.2
• /
• pp.31-39
• /
• 2011

More than sixty percentage of highway in South Korea were constructed by concrete pavements and more than half of the concrete pavements were twenty years or older. Maintenance and rehabilitation of aged cement concrete pavements required early transportation opening due to difficulty of preparing bypass roads, given South Korea's transportation condition and so far, mostly asphalt concrete overlay has been used. However, asphalt concrete pavement maintenance and rehabilitation is costly because of early damage and at the same time, it causes inconvenience to the road users. Recently, as an effective method of rehabilitation for aged cement concrete pavement, bonded concrete overlay is being attempted. Therefore, utilizing various data on year-by-year basis is needed to rationally analyze of the damage on asphalt concrete overlay and bonded concrete overlay is necessary. However, in South Korea database of Serviceability damage on asphalt concrete overlay and bonded concrete overlay does not exist. In this research, performance is evaluated by the LTPP (Long Term Pavement Performance) Data of U.S.A, which accumulated various damage data of asphalt concrete overlay and bonded concrete overlay. However, the pattern distress of asphalt concrete overlay and bonded concrete overlay are different. Therefore, the pavement distress data of each section is collected into database and distress are calculated PCI(Pavement Condition Index) in order to compare life of asphalt concrete overlay and bonded concrete overlay.

• International Journal of Highway Engineering
• /
• v.6 no.1 s.19
• /
• pp.13-23
• /
• 2004

This paper presents the results of a study that was performed to evaluate structural behaviors and related distress of asphalt pavements on concrete bridge deck based on the visual inspection and 3-dimensional finite element analysis. As a result, three most failure types were found such as permanent deformation, potholes, and fatigue crackings. In addition, the failure mechanisms of different types of concrete bridge deck were investigated. An increase in fatigue of asphalt pavements on concrete bridge deck was observed and confirmed by the results from the visual inspections. In consequence, the aging and stripping of asphalt surfacing materials are relatively dominant factors on fatigue rather than traffic loadings.

• International Journal of Highway Engineering
• /
• v.13 no.1
• /
• pp.207-221
• /
• 2011

More than sixty percentage of highway in South Korea were constructed by concrete pavements and more than half of the concrete pavements were twenty years or older. The most of highway have difficulty in providing detour due to the traffic and road condition of South Korea. So far, asphalt concrete has been used for the overlay of aged cement concrete pavement. However, the frequent early damage and maintenance of typical asphalt overlay due to repetitive maintenance causes inconvenience of road users and expensive costs. It is necessary to investigate the factors affecting the performance of asphalt concrete overlay to improve the performance of asphalt overlay. However, the performance data of asphalt concrete overlay in South Korea does not exist. In this research, to investigate on the factors affecting the life of asphalt concrete overlay was attempted based on statistical analysis of the performance data of asphalt concrete overlay included in LTPP (Long-Term Pavement Performance) Database of U.S.A.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.38 no.2
• /
• pp.311-317
• /
• 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
• /
• v.2 no.1
• /
• pp.135-145
• /
• 2000

A new procedure needs to be developed to predict the dynamic layer properties under moving truck loads. In this study, a computer code to evaluate layer moduli of asphalt concrete pavement from measured interior deflections at various depths were developed and verified from numerical model tests. Interior deflections of the pavement are measured from Multi-Depth Deflectometer(MDD). It was found that errors between the given and backcalculated moduli in numerical analysis were less than 0.32% for several numerical models tested. When impact loads were used, a technique to determine the depth to virtual rigid base was proposed through the analysis of compressive wave velocity and impulse loading durations. It was found that errors between the given and backcalculated moduli in numerical analysis were less than 0.114% when virtual rigid base was considered in numerical analysis. The pavement behavior must be evaluated under various vehicle speeds when determining the dynamic interaction between the loading vehicle and pavement system. To evaluate the dynamic behavior on asphalt concrete pavement under various vehicle speeds, truck moving tests were carried out. From the test results with respect to vehicle speed, it was found that the vehicle speed had significant effect on actual response of the pavement system. The lower vehicle speed generates the higher interior deflections, and the lower dynamic modulus.

• Journal of the Korean Society of Hazard Mitigation
• /
• v.9 no.1
• /
• pp.21-25
• /
• 2009

The results of a recent case study for material characterizations and structural evaluation to design asphalt overlay thickness of William P Hobby airport in Houston, Texas are presented herein. The existing runway 12R-30L of Hobby airport consisted of thick asphalt overlay over Portland Cement Concrete (PCC) and the localized surface shoving as evident in the closure of surface groove has been observed recently. Using the field cored asphalt concrete mixtures, measurements of percent air voids, asphalt content and aggregate gradation were conducted to find out the causations of surface shoving and groove closure. The FAA layered elastic program, LEDFAA was utilized to evaluate pavement structural conditions for new asphalt overlay. Two different composition assumptions for existing pavement were made to evaluate the pavement as followings: 1) APC, Asphalt Concrete Overlay over PCC pavement and 2) AC, Asphalt Concrete pavement. Based on laboratory testing results, a ratio of percent passing #200 to asphalt content ranged 1.1 to 2.2, which is considered a high ratio and a tendency of tender mix design was observed. Thus, the localized surface shoving and groove closure of the runway 12R-30L could be attributed to the use of excessive fine contents and tender mix design. Based on the structural evaluation results, it was ascertained that the analysis assuming the pavement structure as AC pavement gives more realistic structural life when the asphalt overlay is thicker enough compared to PCC layer because the existing PCC pavement under asphalt overlay acts more like a high quality base material.

• International Journal of Highway Engineering
• /
• v.13 no.4
• /
• pp.61-70
• /
• 2011

This study developed a permanent deformation model for asphalt concrete based on shear properties. Repeated load triaxial compression (RLTC), triaxial compressive strength, and indirect tension strength tests were performed for the three types of asphalt mixtures at various loading and temperature conditions to correlate shear properties of asphalt mixtures to rutting performance. For the given mixtures, as testing temperature increased, cohesion decreased, but friction angle was insensitive to temperature at $40^{\circ}C$ or higher. It was observed that deviatoric stress, confining pressure, temperature, and load frequency affected the permanent deformation of asphalt mixtures significantly. The permanent deformation model based on shear stress to strength ratio and loading time was developed using the laboratory test results and calibrated using accelerated pavement test data. The proposed model was able to predict the permanent deformation of the asphalt mixtures in a wide range of loading and temperature conditions with constant model coefficients.

• 도로교통
• /
• s.73
• /
• pp.154-161
• /
• 1997

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.32 no.1D
• /
• pp.33-39
• /
• 2012

More and more pavements are suffering from damage these days due to the below-zero winter temperatures and frequent snowfalls. From this research, the freeze-thawing mechanisms of pavements will be observed, and the freeze-thawing resistance of porous asphalt concrete mixture is to be evaluated according to various assessment methods. The investigation was conducted through applying rigid and flexible pavements to freeze-thawing resistance experiments, which include various experiments such as deformation rate measurements, Lottman tests, repeated cyclic freeze-thawing experiments, stripping resistance tests and so on. Test results revealed that the porous asphalt concrete had less deformations according to temperatures compared to dense-graded asphalt concrete due to the 20% void gap. In addition, according to the freeze-thawing repetition experiments which are effected by moisture, the porous asphalt concrete mixture showed superior resistance to repeated cyclic freeze-thawing compared to other asphalt concrete mixtures due to the drainage and the voids within the specimen.

• 한국방재학회:학술대회논문집
• /
• 2009.02b
• /
• pp.120-120
• /
• 2009