• Journal of Construction Engineering and Project Management
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• 제2권1호
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• pp.35-44
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• 2012

In the last two decades, several tele-operated and machine-vision-assisted systems have been developed in the construction and maintenance area, such as pavement crack sealing, sewer pipe rehabilitation, and excavation. In developing such tele-operated and machine-vision-assisted systems, trajectory plans are very important tasks for the optimal motions of robots whether their environments are structured or unstructured. This paper presents an optimal trajectory planning algorithm used for a machine-vision-assisted automatic pavement crack sealing system. In this paper, the performance of the proposed optimal trajectory planning algorithm is compared with the greedy trajectory plans, which are used in the previously developed pavement crack sealing systems. The comparison is based on the computational cost vs. the overall gains in crack sealing efficiency. Finally, it is concluded that the proposed algorithm plays an important role in the productivity improvement of the developed automatic pavement crack sealing system.

• 한국도로학회논문집
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• 제18권4호
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• pp.9-18
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• 2016

PURPOSES : This study aimed to evaluate the performance of pavement management works and to develop a function for estimating the level of service (LOS) and cost of service (COS) for the systematic and quantitative management of pavement performance in the public sector. METHODS : The International Roughness Index (IRI) was used as the performance index for pavement management. Long-term pavement performance data for a period of 7 years (2007-2014) collected by the National Highway Pavement Management System and historical maintenance budget data published by the South Korean government were used to develop the LOS-COS function. Based on the function, a model for estimating the appropriate budget as well as the network conditions was suggested. RESULTS : There was high degree of correlation between pavement performance and the investment level (R = - 0.74). The developed LOS-COS function suggested that the unit cost to improve the network IRI to 1 m/km was 32.6 billion KRW. Further, the maintenance costs normalized with respect to the LOS levels were LOS-A = 88.2 billion KRW, LOS-B = 55.6 billion KRW, and LOS-C = 23.0 billion KRW. CONCLUSIONS : This study proposes a simple way of developing a LOS-COS function. It also shows how to develop a network budget demand and condition estimation model using the LOS-COS function. In addition, it is the first attempt to evaluate the road maintenance budget in South Korea. It is expected that these results will help in the negotiations between the road managers and budget makers.

• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.596-601
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• 2013

In the current pavement construction practice, the state agencies traditionally determine the quality of the as-constructed pavement mix based on individual mixture material parameters (e.g., air voids, cement or asphalt content, aggregate gradation, etc.) and consider these parameters as key variables to influence payment schedule to the contractors and the present and future quality of the as-constructed mixture. A set of empirically pre-determined pay adjustment schedule for each parameter that was differently developed and being used by the individual agencies is then applied to a given project, in order to judge whether each parameter conforms to the designated specifications and consequently the contractor may either be rewarded or penalized in accordance with the payment schedule. With an improved quality assurance system, the Performance Related Specification, the individual parameters are not utilized as a direct judgment factor; rather, they become independent variables within a performance prediction function which is directly used to predict the performance. The quantified performance based on the prediction model is then applied to evaluate the pavement quality. This paper presents the brief history of the quality assurance in asphalt pavement construction including the Performance Related Specifications, statistical performance models in terms of fatigue and rutting distresses, as an example of the performance prediction models, and envisions the possibilities as to how this Performance Related Specification could be utilized in other infrastructures construction quality assurance.

• 한국도로학회논문집
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• 제20권1호
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• pp.1-8
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• 2018

PURPOSES : Case studies of an asphalt-overlay project with a performance-based contract method were conducted on a national highway in Korea to evaluate the effect of the method on asphalt pavement maintenance. This study evaluated the procedure of the performance-based contract method. METHODS : In this study, an asphalt-pavement maintenance project for a national highway was assessed with a performance-based contract to investigate the advantage of the new contract procedures. This is the first trial applying the performance-based contract to a pavement-rehabilitation project in Korea. In the four case studies, the warranty period of the performance-based contract was designed for seven years. The research team monitored the construction site to compare the normal contract method with the performance-based contract method. The case studies' project sites were investigated after the end of the construction. RESULTS : Based on the limited case studies, the performance-based contract method could extend the service life of the asphalt pavement and reduce the pavement-maintenance budget because the quality control was well managed by the contractors. However, a few construction laws would be necessary to apply the performance-based contract method in the future. CONCLUSIONS : Using the performance-based contract, the construction company made great efforts to guarantee the warranty period and to apply the optimal maintenance method, based on the pavement distress condition. The contractor and the agency would need to understand the new performance-based contract system for it to be activated. Therefore, a proper education program for the performance-based contract system would be needed to educate the stakeholders regarding the procedures and their effects on the pavement management and maintenance.

• 한국도로학회논문집
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• 제15권3호
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• pp.9-16
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• 2013

PURPOSES: There is a need to develop a method to incorporate tire-pavement noise in the pavement management system. Tire-pavement noise highly depends on the characteristics of pavement texture. Therefore, estimation of texture characteristics may give useful information to predict tire-pavement noise. This study aimed to find the relationship between tire-pavement noise and MPD(Mean Profile Depth) for concrete pavement. METHODS: MPD and tire-pavement noise were collected on the number of expressway sections including Central Inland Test Road in Korea. Statistical analysis was performed to find the correlationship between MPD and tire-pavement noise. In addition, multiple regression analysis to find the tire-pavement noise based on MPD and type of concrete pavement texture. RESULTS: Linear relationship between MPD and tire-pavement noise is observed for concrete pavement. Furthermore, a forensic equation to estimate tire-pavement noise based on MPD and texture types of concrete pavement is suggested. CONCLUSIONS: Tire-pavement noise on concrete pavement can be predicted based on the consideration of texture type and MPD estimation.

• 한국콘텐츠학회논문지
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• 제11권12호
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• pp.919-930
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• 2011

도로는 사회간접자본 중 하나로서 지속적으로 관리되어야 그 기능을 발휘할 수 있는 국가의 중요한 자산이다. 지금까지는 도로를 포장관리시스템이라는 체계로 관리하여 왔다. 이 포장관리시스템은 시설물유지관리차원에서 사회기반시설을 관리하는 것으로서 주로 관리자 관점에서 공학적 판단을 기준으로 최소의 비용으로 공용수명을 최대화하는 모델이다. 그러나 경제발전으로 국민의 소득수준이 올라감에 따라 삶의 질에 대한 요구도 증가하고 있어 이제는 납세자로서 국민의 동의는 국가의 정책을 결정하는데 중요한 변수로 작용하기 시작했다. 따라서 사용자 관점의 평가는 이러한 요구를 해결하는 출발점이 되었다. 이런 관점으로 평가하기 위한 척도로서 서비스 수준(Level of Service: LoS) 이라는 것이 사용되기 시작했으며, 이를 시설물 자산관리에 활용하려는 여러 가지 시도가 있다. 본 논문에서는 LoS를 척도로 활용하는 한국형통합 자산관리체계(Korea Total Asset Management-40: KTAM-40)를 적용한 도로포장자산관리시스템의 정보기술아키텍처 중에 응용아키텍처와 데이터아키텍처를 설계하고 이것이 KTAM-40의 요구조건을 충족시키는지를 밝히고자 한다.

• 한국도로학회논문집
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• 제4권3호
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• pp.25-33
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• 2002

국가 기간산업의 중추 역할을 수행하는 일반 국도는 대부분 일반 아스팔트 포장으로 되어 있으며, 최근 들어 고온 및 중차량의 증대로 인해 포장의 수명이 급격히 줄어들고 있는 실정이다. 이런 이유로 많은 경우 신설포장에 대해서는 SMA. 개질아스팔트 등 특수포장이 적용되고 있다. 그러나 어떤 경우에 특수 포장을 채택할 것인가에 대한 적용 기준이 명확히 제시되어 있지 않아 설계 실무자들이 포장형식 선정을 위한 의사 결정에 많은 어려움이 있다. 본 연구에서는 이에 대한 부분적인 해결책으로 과거 10여 년 동안 수행된 국도 포장유지관리시스템의 자료를 이용하여 교통량에 따른 일반 아스팔트포장의 수명을 분석하였다. 분석결과 신설포장은 9.5년, 덧씌우기 포장은 5.6년으로 나타났다. 또한 현재의 포장 수명에 대한 분포 자료를 이용하여 설계 수명인 10년을 공용하기 위한 교통량을 신뢰수준에 따라 제시하였다. 그 결과 90%의 신뢰수준에서는 8.2ton 표준 축하중 2,300 ESAL, 80% 신뢰수준에서는 8.2ton 표준 축하중 1,500 ESAL로 나타났다 즉, 여기서 제시된 교통량보다 많은 구간에 대해서는 특수 포장의 적용을 검토할 것을 제안한다.

• 한국도로학회논문집
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• 제19권5호
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• pp.117-129
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• 2017

PURPOSES : The purpose of this study is to analyze the performance life of hot central plant recycling (HCPR) and hot in-place recycling (HIR) pavements applied to the National Highway for the past 20 years and compare it with conventional hot-mix asphalt (HMA) pavement. METHODS : In order to analyze the performance life of recycling asphalt pavements, a comprehensive literature review was conducted to investigate the government law and official system for the use of recycling asphalt pavement in Korea and foreign countries. Next, the application information of using a hot central plant recycling and hot in-place recycling pavements in the national highway is collected from the database of pavement management system (PMS) and then their field condition is visually surveyed. Finally, the performance life of recycling asphalt pavements in the national highway is analyzed and compared with conventional hot-mix asphalt pavement. RESULTS :Institutions are encouraging the promotion of using recycled asphalt pavement through various legal systems in Korea as well as abroad. Based on analysis results for the average performance life of hot central plant recycling pavement applied to the national highway, the average performance life is estimated to be 10.2 years. However, the average performance life of in-place recycling pavement is estimated to be 6.5 years. However, it is expected to increase performance life after the HIR construction system is modified. CONCLUSIONS : Based on the limited data analysis of the performance life of recycled asphalt pavements, HCPR shows similar performance life to conventional asphalt pavement but HIR shows shorter performance life than conventional asphalt pavement. However, it is noted that all performance life data is very limited and it should be monitored and analyzed further.

• 실천공학교육논문지
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• 제11권1호
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• pp.33-41
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• 2019

도로포장공사는 시방규정에 맞는 재료를 포설하고 다짐장비를 가동하여 이를 적절한 강도를 가질 수 있도록 다짐하는 공정이 큰 부분을 차지한다. 지난 15년간 유럽 및 미국에서 도로포장공사용 다짐장비 및 시공법의 비약적인 발전이 있었다. GPS 및 각종 센서가 부착된 지능형 다짐 장비가 가동하면서 지반/포장 구조체의 반응 및 다짐장비의 위치 등을 실시간으로 구할 수 있게 되어, 이를 공사품질관리에 이용할 수 있게 된 것이다. 국내에서도 이러한 시공체계를 도입하기 위한 기초연구가 진행되고 있다. 본 연구를 통하여 증강현실기반의아스팔트 포장 다짐공사 지원체계를 제안하고 이를 공사담당자가 적절히 활용할 수 있는 교육과정 및 내용을 제안하였다. 세계적으로 아직 시도된 바 없는 AR환경에서의 IC 다짐장비 시공관리를 통하여 아스팔트 포장 다짐공사의 시공품질을 극대화할 수 있을 것으로 판단된다.

• 한국도로학회논문집
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• 제10권3호
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• pp.221-230
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• 2008

우리나라는 1987년 국도 PMS가 도입된 이래 국도 및 고속도로의 경우 그동안 도로포장의 상태를 평가할 수 있는 포장상태 평가기준을 마련하여 이를 바탕으로 유지보수를 시행하고 있다. 반면, 시단위 도로의 경우 비교적 많은 교통량이 통행하며, 가장 많은 연장을 차지하고 있으나 서울시의 경우를 제외하고는 포장상태를 평가할 수 있는 마땅한 시스템이 거의 없는 실정이다. 따라서 본 연구에서는 서울시 사례 및 기타 시단위 도로포장상태 조사자료를 토대로 아스팔트포장의 일반적 평가요소인 균열, 소성변형, 종단평탄성 등 3가지 요소에 대한 포장상태를 분석하였으며, 시단위 도로의 유지관리 의사결정에 필요한 포장평가지수를 개발하였다. 본 연구의 포장평가지수 개발방법은 현장조사와 샘플구간에 대하여 전문가 그룹을 구성하여 설문조사를 실시한 후 통계적 처리를 거쳐 시단위 포장평가지수(MPCI)를 제시하였다. 또한 개별결함 지수에 대한 민감도 분석을 실시하였으며, 평가지수를 실제 현장에 적용하여 타 기관에서 사용중인 포장평가지수와의 비교를 통하여 그 적정성을 검증하였다.