• 제목/요약/키워드: road materials

검색결과 642건 처리시간 0.022초

폴리우레탄을 이용한 자전거도로의 탄성포장재 특성 (Characteristic of Elastic Paving Materials in Bicycle Road using Polyurethane)

  • 이영세
    • 한국산업융합학회 논문집
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    • 제17권1호
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    • pp.7-14
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    • 2014
  • In this study, characteristic of elastic paving materials in bicycle road using polyurethane were studied experimentally. As a results, following their good result was obtained. Bicycle road packaging materials are flexural strength g test, ratio of mass change after freezing and thawing, repulsion elasticity test, water Permeation coefficient test and slip resistance test results showed good performance.

복합신소재 도로구조물의 변환단면이 고유진동수에 미치는 영향 (The Effects of Different Cross Section on Natural Frequency of the Advanced Composite Materials Road Structures)

  • 한봉구
    • 한국도로학회논문집
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    • 제15권3호
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    • pp.23-29
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    • 2013
  • PURPOSES: This paper aims to give a guideline and the way to apply the advanced composite materials theory to the road structures with different cross sections to the practicing engineers. METHODS: To simple but exact method of calculating natural frequencies corresponding to the modes of vibration of road structures with different cross sections and arbitrary boundary conditions. The effect of the $D_{22}$ stiffness on the natural frequency is rigorously investigated. RESULTS: Simple method of vibration analysis for calculating the natural frequency of the different cross sections is presented. CONCLUSIONS: Simple method of vibration analysis for calculating the natural frequency of the different cross sections is presented. This method is a simple but exact method of calculating natural frequencies of the road structures with different cross sections. This method is extended to be applied to two dimensional problems including composite laminated road structures.

한국 도로 자본이 산업에 미친 영향과 생산성 분석 (Study on The Influence of Road Capital to Industry and Productivity Growth in South Korea)

  • 국우각
    • 한국도로학회논문집
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    • 제15권2호
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    • pp.169-181
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    • 2013
  • PURPOSES : This study is to suggest the Influence of road capital to industry and productivity growth in South Korea. METHODS : Based on the literature review, The relevant policy questions addressed in this report are : cost reduction and Scale elasticities of road, effect of road capital stock on demand for labor, capital and materials, marginal effect of road, industry TFP growth decomposition. RESULTS : The marginal benefits of the road capital at the industry level were calculated using the estimated cost elasticities. Demand for the road capital services varies across industries as do the marginal effects. The marginal benefits are positive for the principal industries. This suggests that for these industries the existing stock of road capital may be under supplied. The contribution of road capital to TFP growth is positive in principal industries. The main contribution of road capital is in the manufacturing industries ; the magnitudes of contribution varies among industries. These results indicate that growth in exogenous demand is most important contributor to TFP growth. CONCLUSIONS : The road capital have a significant effect on employment, private capital and demand for materials inputs in all industries. At a given level of output, an increase in road capital lead to variety to demand for all inputs in all industries.

New Frontiers in Hard Materials Testing

  • Gee, Mark;Gant, Andrew;Morrell, Roger;Roebuck, Bryan
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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    • pp.885-886
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    • 2006
  • Significant advances in mechanical testing for hard materials are discussed in this paper. There are three specific areas that are covered. In the measurement of fracture toughness factors such as the control of slow crack growth to produce strating cracks, and evaluating reproducibility and repeatability of tests have been recently examined. The miniaturization of tests reduces the amount of material that is used in testing, improves the throughput of tests, and also improves cost effectiveness. New techniques such as stepwise testing and micro scratch testing have contributed to significant additions to the knowledge of the wear mechanisms that operate in these materials.

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Methyl Methacrylate(MMA)계 도로보수재의 기초 물성 평가 (Evaluation of Basic Properties of Methyl Methacrylate (MMA) as a Road Repair Material)

  • 최병철;김규용;편수정;지성준;유하민;남정수
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2023년도 가을학술발표대회논문집
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    • pp.109-110
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    • 2023
  • Domestic ultra-hard road repair materials require a lot of time before the road can be opened to traffic. Therefore, in this study, Methyl Methacrylate (MMA) based road repair material was used to improve the above problems. Furthermore, the basic physical properties of MMA-based pavement repair materials are examined to confirm their suitability in concrete pavements. For this study, two types of MMA road repair materials (A type and B type) were selected. Then, the curing of the test specimens prepared for painting was carried out under three conditions. The experimental items were viscosity (drop time) and drying time (set to touch, dry-hard). As a result of the experiment, viscosity (drop time) was faster in type A than in type B. The drying time results were as follows. In the case of set ti touch, both type A and type B dried in about 10 minutes regardless of the curing conditions. In the case of dry-hard, regardless of the curing conditions, A type dried longer than B type, but it dried faster than conventional road repair materials. Therefore, within the scope of this study, it is considered that A type has a high potential for utilization as a road repair material.

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보조기층재로서 폐콘크리트의 안정성에 관한 연구 (A Study on the Stability of the Waste Concrete as the Subgrade Materials)

  • 김태봉;박원철;서상구;안상로
    • 한국안전학회지
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    • 제11권3호
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    • pp.160-167
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    • 1996
  • The construction waste concrete produce from the demolished concrete structures. These waste concrete materials are useful and valuable for fill and subgrade and are considered to use as the subgrade material of the road. To use the subgrade of the road with the waste concrete, the several experiments involved with compaction test and laboratory C. B. R. etc. are performed. These experiments are compared with criteria of the road construction manual. It is shown that the quality of the construction waste concrete satisfies that of the subgrade mentioned in the road construction manual.

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압전 캔틸레버 구조와 차량하중 전달방법에 따른 도로용 에너지 하베스터의 설계 및 평가 (Development and Evaluation of the Road Energy Harvester According to Piezoelectric Cantilever Structure and Vehicle Load Transfer Mechanism)

  • 김창일;김경범;정영훈;이영진;조정호;백종후;강인석;이무용;최범진;박신서;조영봉;남산
    • 한국전기전자재료학회논문지
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    • 제25권10호
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    • pp.773-778
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    • 2012
  • A road energy harvester was designed and fabricated to convert mechanical energy from the vehicle load to electrical energy. The road energy harvester is composed of 16 piezoelectric cantilevers. We fabricated prototypes using a vehicle load transfer mechanism. Applying a vehicle load transfer mechanism rather than directly installing energy harvesters under roads decreases the area of road construction and allows more energy harvesters to be installed on the side of the road. The power generation amount with respect to the vehicular velocity change was assessed by installing the vehicle load transfer mechanism form and underground form. The energy harvester installed in the underground form generated power of 4.52 mJ at the vehicular velocity of 50 km/h. Also, power generation of the energy harvester installed in the vehicle load transfer mechanism form was 48.65 mJ at the vehicular velocity of 50 km/h.

도로 융설제 성능 평가와 적정 사용량 산정 (Performance and Adequate Usage of Deicing Materials)

  • 윤덕근;정준화
    • 한국도로학회논문집
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    • 제8권1호
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    • pp.55-64
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    • 2006
  • 동절기 도로 유지관리는 일반적으로 제설활동을 의미하며 제설활동에는 도구를 사용하여 물리적으로 눈을 제거하는 방법과 융설제를 사용하여 화학적으로 눈을 제거하는 방법 이 포함된다. 융설제를 사용하여 화학적으로 눈을 제거 할 때, 융설제를 과도하게 사용하면 환경문제와 예산낭비가 생길 수 있고, 융설제를 적게 사용하면 그 성능을 충분히 낼 수 없으므로 얼마나 사용해야 하는지는 중요한 문제이다. 본 연구에서는 실내 및 현장 실험을 통해 제설제의 성능을 평가하고 이를 바탕으로 도로 제설작업시 적정 융설제 살포량을 제안하였다.

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복합신소재 도로구조물의 형상비가 고유진동수에 미치는 영향 (The Effects of the Aspect Ratio on Natural Frequency of the Advanced Composite Materials Road Structures)

  • 한봉구
    • 한국도로학회논문집
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    • 제15권3호
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    • pp.17-22
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    • 2013
  • PURPOSES: Current theories for composite structures are too difficult for design engineers for construction. The purpose of this paper is to demonstrate to the practicing engineers, how to apply the advanced composite materials theory to the road structures. METHODS: Some laminate orientations have decreasing values of $D_{16}$, $B_{16}$, $D_{26}$ and $B_{26}$ stiffnesses as the ply number increases. The plate aspect ratio considered is from 1 to 5. In order to study the effect of $M_x$ on the equilibrium equations, two cases are considered. $M_x$ term is considered or neglected. RESULTS: Most of the road structures have high aspect ratios, for such cases further simplification is possible by neglecting the effect of the longitudinal moment terms. CONCLUSIONS: Most of the road structures have plate aspect ratios higher than 2. It is concluded that, for all boundary conditions, neglecting the longitudinal moment($M_x$) terms is acceptable if the aspect ratio (a/b) is equal to or higher than 2. This conclusion gives good guide line for design of the road structures.

도로건설재료로 순환골재의 공학적·환경적 특성에 관한 기초연구 (The Engineering and Environmental Properties of Reclaimed Concrete Materials as Road Materials)

  • 이용수;권용완;현재혁
    • 한국지반환경공학회 논문집
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    • 제6권3호
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    • pp.17-23
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    • 2005
  • 매년 콘크리트구조물의 해체로 폐콘크리트는 증가하고 있으며, 해체되어 발생한 폐콘크리트 덩어리를 순환골재로 만들어 도로재료로 재활용하고 있다. 그러나 폐콘크리트의 공학적 환경적 안정성에 대한 연구가 미흡하여 재활용율이 낮다. 본 논문은 이러한 문제점을 해결하기 위하여 일반쇄석과 순환골재의 비교 분석을 실시하였다. 순환골재의 공학적 특성 시험인 액성한계, 소성지수, CBR, 모래당량, 마모시험과 환경적 특성시험인 pH, 컬럼용출 시험을 실시하였다. 실험결과, 순환골재의 공학적 특성은 노체, 노상, 보조기층에 적합한 것으로 나타났으나, 기층재료로는 부적합한 것으로 나타났다. 순환골재의 환경적 특성으로 pH, 장기용출시험결과, pH는 11정도로 나타났으며, 용출시험결과는 폐기물관리법의 환경기준치 이내로 비교적 안전한 것으로 나타났다. 따라서, 순환골재를 도로재료로 활용하더라도 공학적 환경적으로 안전한 것으로 판단된다.

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