• International Journal of Highway Engineering
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• v.4 no.3 s.13
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• pp.1-13
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• 2002

Design methods for new flexible pavements and overlays are in the transition from empirical to mechanistic approach, and many state highway agencies trend to move toward the adoption and use of mechanistic-empirical (M-E) design in new constructions and rehabilitations of flexible pavements. Hence, the Michigan Department of Transportation (MDOT) decided to develop a M-E flexible pavement design procedure, in which major pavement distresses such as fatigue cracking and rutting are employed as indicators of the serviceability of a flexible pavement. The main concept of the developed design procedure is that a designed pavement that is supposed to carry a certain number of traffic must satisfy designated thresholds of rut depths and fatigue lives during a service period. For the M-E design procedure, transfer functions were developed to predict rut-depths and fatigue lives. These functions related the pavement responses to pavement performance. For validation, three current new flexible pavement design cases were obtained from the MDOT. In these cases, asphalt concrete (AC) layer thicknesses determined by the suggested M-E procedure compare favorably with those determined by the current MDOT design practice that is based on AASHTO design guide. This finding implies that the suggested Michigan M-E flexible pavement design procedure can provide a good opportunity to improve the current design practice.

• Journal of the KSME
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• v.34 no.5
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• pp.384-391
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• 1994

지금까지 고분자 재료에서의 일반적인 파괴역학 연구실태를 집약해보았다. 이 분야의 연구결과 들은 금속의 파괴역학 문제와는 다른 새로운 문제점을 지니고 있었다. 우리는 여기서 잘 짜여진 문제의 해를 구했다기 보다는 문제를 정의하는 수준에 있음을 느낄수 있었다. 더욱이 고려되고 있는 문제들조차 서로 독립적으로 연관성을 보이고 있지 못하다. 접근방법이 너무 이론적이어서 실제상황에 적합하지 않거나 실험적인 검증이 요구되고, 경우에 따라서는 경험적이어서 해석 적인 정량화가 필요한 경우가 많다. 의심할바 없이 이것이 고분자재료 파괴역학의 현실이며 앞 으로 좀더 많은 해석적, 실험적 연구가 이루어져 상황이 개선될 것으로 믿는다.

• 한국도로학회지:도로
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• v.3 no.4 s.10
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• pp.52-53
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• 2001

• International Journal of Highway Engineering
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• v.14 no.3
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• pp.15-24
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• 2012

The MEPDG(Mechanistic-Empirical Pavement Design Guide) developed based on the AASHTO Design Guide helps engineers find optimal alternatives by using traffic volume, climate, material property, and pavement structure as its input parameters. However, because technical problems were found in the MEPDG, efforts to improve the program by settling the problems have been continued. Meanwhile, another mechanistic-empirical design program has been developed by the KPRP(Korea Pavement Research Program) in Korea. To develop and improve the Korean design program reasonably, it is necessary to analyze the MEPDG and then compare programs each other. For concrete pavement, fatigue cracking is predicted by using very complicated logic different from other performance indicators. Therefore, in this paper, transfer functions of the fatigue cracking used in the version of 0.5, 1.0, and 1.1 of the MEPDG were analyzed. Sensitivity of the input parameters to the cumulative fatigue damage was compared to each other by the MEPDG version and KPRP.

• International Journal of Highway Engineering
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• v.10 no.4
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• pp.79-89
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• 2008

The pavement performance model is the most important factor to determine the pavement life in the mechanistic-empirical pavement design guide (MEPDG). As part of Korean Pavement Research Program (KPRP), the Korean Pavement Design Guide (KPDG) is currently being developed based on mechanistic-empirical principle. In this paper, the rutting prediction model of asphalt mixtures, one of the pavement performance model, has been developed using triaxial repeated loading testing data. This test was conducted on various types of asphalt mixtures for investigating the rutting characteristics by varying with the temperature and air void. The calibration process was made for the coefficients of rutting prediction model using the accelerated pavement testing data. The accuracy of prediction model can be increased when by considering the effect of individual rutting properties of materials rather than shear stresses with depths.

• Journal of the Society of Disaster Information
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• v.9 no.1
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• pp.1-10
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• 2013

The main objective of this research is to develop the Mechanistic-Empirical (M-E) guidelines for evaluating the capacity of existing highways to sustain route overweight truck traffic over a specified performance period due to a growing concern on the impact of increasing overweight truck loads on highways. In this study, a two-stage framework was developed for this purpose. Level I procedure involves the use of pavement evaluation charts to identify the best possible route from among the alternatives considered and to determine what additional tests and analyses are needed as a screening tool. Level II involves the application of the Overweight Truck Route Analysis (OTRA) program to evaluate the structural adequacy of an existing route to carry routine overweight truck traffic over the specified performance period along with estimating asphalt concrete overlay thickness, if necessary.

• 한국도로학회:학술대회논문집
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• 2002.10a
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• pp.301-308
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• 2002

• 한국도로학회:학술대회논문집
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• 2011.03a
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• pp.45-53
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• 2011

• Journal of the KSME
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• v.29 no.3
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• pp.253-260
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• 1989

본 글에서는 다공질재료의 구성방정식의 개발을 위한 이론적 접근방법을 논하고자 한다. 여기서 부분적으로는 미소역학적인 중공구형 모델을 사용하고, 또 부분적으로는 경험적 방법 또는 현 상학적 방법들을 사용한다.

• International Journal of Highway Engineering
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• v.13 no.1
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• pp.33-40
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• 2011

The resilient modulus which is presented mechanical properties of compacted subbase material is the design parameter on the Mechanistic - Empirical pavement design guide. The compaction control method on the Mechanistic - Empirical pavement design guide will be the way to confirm whether the in-situ elastic modulus measured after the compaction meets the resilient modulus which is applied the design. The resilient modulus in this study is calculated by the neural network suggested by Korea Pavement Research Program, and degree of compaction as the existing compaction control test and plate bearing capacity test(PBT) was performed to confirm whether the in-situ elastic modulus is measured. The Light Falling Weight Deflectometer(LFWD) is additionally tested for correlation analysis between each in-situ elastic modulus and resilient modulus, and is proposed correlation equation and test interval which can reduced overall testing cost. Also, the subbase compaction control procedure based on the in-situ elastic modulus is proposed using the in-situ PBT and LFWD test result.