• 한국도로학회논문집
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• 제18권4호
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• pp.19-28
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• 2016

PURPOSES : Long-life asphalt pavements are used widely in developed countries. In order to be able to devise an effective maintenance strategy for such pavements, in this study, we evaluated the performance of the long-life asphalt pavements constructed along the national highways in South Korea. Further, an economic evaluation of the long-life asphalt pavements was performed based on a life-cycle cost analysis. We aimed to devise a model for evaluating the performance of long-life asphalt pavements using the national highway pavement management system (PMS) database as well as for analyzing the economic feasibility of such pavements, in order to promote their use in South Korea. METHODS : The maintenance history and pavement performance data were obtained from the national highway PMS database. The pavement performances for a total of 292 sections of 10 lanes (5 northbound lanes and 5 eastbound lanes) of national highways were used in this study. Models to predict the performances of hot mix asphalt (HMA) and long-life asphalt pavements under two distinct traffic conditions were developed using a simple regression method. Further, the economic feasibility of long-life asphalt pavements was evaluated using the Korea Pavement Management System (KoPMS). RESULTS : We developed service-life prediction models based on the traffic volume and the equivalent of single-axle load and found that long-life asphalt pavements have service lives 50% longer than those of HMA pavements. Further, the results of the economic analysis showed that long-life asphalt pavements are superior in terms of various economic indexes, including user cost, delay cost, total cost, and user benefits, even though their maintenance cost is higher than that of HMA pavements. A comparison of the economic feasibilities of the various groups showed that group A is superior to HMA pavements in all aspects except in terms of the maintenance criterion (crack 20% or higher) as per the NPV index. However, the long-life asphalt pavements in group B were superior in terms of the maintenance criterion (crack 25% or higher) regardless of the economic feasibility. CONCLUSIONS : The service life of long-life asphalt pavements was found to be approximately 50% longer than that of HMA pavements, regardless of the traffic volume characteristics. The economic feasibility of long-life asphalt pavements was evaluated based on the KoPMS. The results of the economic analysis were the following: long-life asphalt pavements are exceptional in terms of almost all factors, such as user cost, delay cost, total cost, and user benefit; however, the exception is the maintenance cost. Further, the economic feasibility of the long-life asphalt pavements in group B was found to be better than that of the HMA pavements (crack 25% or higher).

• 한국조경학회지
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• 제34권2호
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• pp.18-25
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• 2006

This study aims to measure and to analyze the thermal environment characteristics of the various permeable pavement materials such as grass pavement (GREEN BLOCK PARK), stone and grass pavement (GREEN BLOCK STEP), stone pavement (GREEN BLOCK MOSAIC) and wood pavement (WOOD BLOCK) under the summer outdoor environment. The thermal environment characteristics measured in the study includes the changes of surface temperature during the day, changes of the temperature on each pavement layer, and long and short wave radiation of each pavement surface. The experimental condition is based on the data on the hottest temperature (August 5, 2005, $34.0^{\circ}C$) of the you. Some of main findings are: 1) The heat environment was worse on the wood pavements than on the stone pavement. This is mainly due to the low albedo of the wood pavements (0.37) while the albedo value of stone pavements is 0.41. Small heat capacity of the wood pavements also contributes to this difference. 2) The heat environment was worse on the stone pavements than on the turf pavements. This was mainly due to the evapotranspiration of the plant growth layer of the turf pavements. 3) The peak surface temperature was the highest on the wood pavements ($56.1^{\circ}C$). The peak surface temperatures on the stone pavements, the stone-grass pavements and the grass pavements were $43.1^{\circ}C,\;40.1^{\circ}C\;and\;37.9^{\circ}C$, respectively. 4) To improve the thermal environments in the urban area, it is recommended to raise the albedo of the pavements by brightening the surface color of the pavement materials. Further studies on the pavement materials and the construction methods which can enhance the continuous evapotranspiration from the pavements surface are needed.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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• pp.573-576
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• 2003

We have developed and applied the super high early strength concrete overlay pavements for repairing asphalts pavements within 24hours. This pavements repairing method by the super high early strength concrete have already applied in U.S.A, japan, England, etc. The super high early strength concrete developed by Ssangyong cement co. for repairing pavements speedily have replaced at No. 2, 17 pavements in managing by Sunchoen national pavements management office. In the results, all of works have finished within 16~24hours after intercepting traffics and all of traffics was opened to be hamonious. In present, this pavements is sound and strong

• 한국도로학회논문집
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• 제18권6호
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• pp.35-40
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• 2016

OBJECTIVES : The objective of this study is to analyze the nonlinear behavior of block pavements using multi-load level falling weight deflectometer (FWD) deflections. METHODS : Recently, block pavements are employed not only in sidewalks, but also in roadways. For the application of block pavements in roadways, the structural capacities of subbase and subgrade are important factors that support the carry traffic load. Multi-load level FWD testing was conducted on block pavements to analyze their nonlinear behavior. The deflection ratio due to the increase in load was analyzed to estimate the nonlinearity of block pavements. Finite element method with nonlinear soil model was applied to simulate the actual nonlinear behavior of the block pavement under different levels of load. RESULTS : The results of the FWD testing show that the center deflections in block pavements are approximately ten times greater than that in asphalt pavements. The deflection ratios of the block pavement due to the increase in the load range from 1.2 to 1.5, indicating that the deflection increased by 20~50%. The material coefficients of the nonlinear soil model were determined by comparing the measured deflections with the predicted deflections using the finite element method. CONCLUSIONS : In this study, the nonlinear behavior of block pavements was reviewed using multi-load level FWD testing. The deflection ratio proposed in this study can estimate the nonlinearity of block pavements. The use of nonlinear soil model in subbase and subgrade increases the accuracy of predicting deflections in finite element method.

• 한국도로학회논문집
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• 제15권3호
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• pp.75-83
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• 2013

PURPOSES: In this study, flood mitigation effect of drainage asphalt concrete pavement were analyzed by a SWMM 5.0 program in order to evaluate the low impact development (LID) based on the drainage asphalt concrete pavements. METHODS: In order to determine the porosity parameters of drainage asphalt concretes, the specimen mixtures were manufactured using the conditions presented in the previous study. The numerical simulation was conducted using the SWMM 5.0 program considering the flood mitigation effect of drainage asphalt concrete pavements. The effect of flood reduction can be observed when drainage asphalt concrete pavements were applied to Mokgamcheon watershed. The flood mitigation effect analysis of Mokgamcheon watershed as well as continuous simulation of subwatershed runoff were performed through this study. RESULTS : The analysis of drainage asphalt concrete pavements was carried out for evaluating the effect on runoff, resulting in: the peak flow decreases up to 1.26~9.53% after drainage asphalt concrete pavements applied in the SWMM 5.0 program furthermore, the discharge decreases up to 0.55~4.11%. CONCLUSIONS: As a result, the reduced peak flow and discharge were found through the SWMM 5.0 program. It can be concluded that the flood is effectively reduced when the drainage asphalt concrete pavements are used.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1989년도 가을 학술발표회 논문집
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• pp.15-18
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• 1989

The planar effects on the concrete pavements Is mainly due to the concrete shrinkage, subgrade friction, and thermal expansion or contraction. A complete understanding of analytical behavior of concrete pavement requires the development of computer model, stiffness matrix and equivalent nodal load matrices due to the effects mentioned above. A computer program, INPLANE II, has been written to evaluate the planar effects on concrete pavements. The planar effects determine to what degree the joint open and also help In determining factors which affect the joint stiffnesses and structural behavior of concrete Pavements.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.791-796
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• 1997

Deterioration of pavements or tunnels primarily from the existence of voids under the pavements or tunnel linings. To detect these voids effectively by non-destructive testes, a method using radar was proposed. In this research, the detection of shape of voids by radar image processing is investigate. The experiments and simulation were conducted to detect voids in or under concrete pavements for tunnel linings) with reinforcing bars. From the results, the fundamental algorithm for tracing the voids, improving the horizontal resolution of the object image and detecting shape of objects, was verified.

• Water Engineering Research
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• 제5권1호
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• pp.37-45
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• 2004

As one alternative to alleviate damages caused by stormwater runoff, the effects of runoff quantity reduction are analyzed when porous pavement is used. Porous pavements with various depths, general pavement and an artificial rainfall generator are installed for laboratory experiments. Runoff changes are analyzed according to the various rainfall durations. The rainfall intensity of 150 mm/hr is generated for 30 minutes, 60 minutes, and 120 minutes. For porous pavements with 80 cm thickness, 100%, 93%, 56% of discharge is infiltrated through soil, respectively. For porous pavements with 20 cm thickness, 81%, 32%, 28% of discharge is infiltrated through soil, respectively. It is found that the porous pavements are able to decrease the runoff.

• Geomechanics and Engineering
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• 제4권3호
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• pp.219-227
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• 2012

Pavement management systems require systematic monitoring of pavement surfaces to determine preventive and corrective maintenance. The process involves the accumulation of large amounts of visual data, typically obtained from site visitation. The pavement surface condition is then correlated to a pavement distress index that is based on a scoring system previously established by state or federal agencies. The scoring system determines if the pavement section requires maintenance, overlay or reconstruction. One of the surface distresses forming part of the overall pavement distress index is the Alligator Crack Index (AC Index). The AC Index involves the visual evaluation of the crack severity of a section of a pavement as being low, medium, or high. This evaluation is then integrated into a formula in order to obtain the AC Index. In this study a quantification of the visual evaluation of the severity of alligator cracking is carried out using photographs and the fractal dimension concept from fractal theory. Pavements with low levels of cracking were found to have a fractal dimension equal to 1.051. Pavements with moderate levels of cracking had a fractal dimension equal to 1.1754. Pavements with high degrees of cracking had a fractal dimension that varied between 1.5037 (high) and 1.7111 (very high). Pavements with a level of cracking equal to 1.8976 represented pavements that disintegrated and developed potholes. Thus, the visual evaluation of the state of cracking of a pavement (the AC Index) could be enhanced with the use of the fractal dimension concept from fractal theory.

• 한국도로학회논문집
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• 제10권2호
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• pp.115-124
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• 2008

본 연구에서는 단지 내 아파트 블록포장 50곳의 현장조사를 통하여 주요 파손형태를 조사하여 공용성을 평가하였다. 공용성 평가결과에 따르면, 조사대상지역에서 9년의 공용연수를 가진 블록포장의 유지관리지수는 7.9에서 8.9사이이며, 블록포장의 상태는 양호한 것으로 나타났다. 따라서 건설교통부 '보도설치 및 관리지침'에 10년으로 제시된 보도의 교체주기는 검토할 필요가 있다는 결론을 도출하였다. 또한 블록포장의 공용성을 객관적으로 평가하기 위해서 일본블록포장협회에서 제시한 유지관리 기준과 건설교통부 '보도설치 및 관리지침'의 유지관리기준을 조합하여 국내 현실에 적합한 유지관리기준을 제시하였다. 외국과 비고할 때 국내의 블록포장의 기준에는 내구성 관련기준과 줄눈채움재 및 모래안정층의 품질관리 기준이 명확히 제시되어 있지 않다. 따라서 블록포장의 기대수명과 유지관리비용을 줄이기 위하여, 본 연구에서는 국내외 기준을 비교하여 이러한 기준들을 국내기준에 포함시킬 것을 제안하였다.