• 제목/요약/키워드: Land aggregate

검색결과 86건 처리시간 0.025초

순환 가열 아스팔트의 용도별 기계적성능 평가 및 경제성 분석 연구 (A Study on Mechanical Performance Evaluation and Economic Analysis by Reclaimed Hot Asphalt Pavement)

  • 문성호;가현길;이시원;박용부
    • 토지주택연구
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    • 제10권4호
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    • pp.51-59
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    • 2019
  • The government is encouraging the notice of obligatory reclaimed asphalt as a result of the economic and social positioning of green growth to reduce the amount of waste resources and to solve natural resource problems by recycling continuously generated waste resources. However, it is necessary to develop application guideline for each application to apply reclaimed asphalt to the site because quality control of the reclaimed asphalt is difficult and the specifications are ambiguous as well. Therefore, in this study, the mix design, quality test, performance test, and finite element analysis about reclaimed Asphalt Pavement were conducted to develop application guideline for reclaimed hot asphalt. The mix design was carried out for the comparative general hot mix asphalt mixture, the reclaimed hot mix asphalt mixture using the additive, and the reclaimed hot mix asphalt mixture without the additive. Indirect tensile strength and tensile strength ratio tests were used to characterize the reclaimed hot mix asphalt mixture. Using the results of dynamic modulus test and FWD test for KPRP analysis and finite element analysis, the performance life was evaluated for general pavement and pavement using recycled aggregate. Finally, the life cycle cost analysis was used to compare and analyze the economics of reclaimed asphalt concrete pavement.

The Research Regarding the Visual Continuity of the Green in the Re-development Area by Using the Aerial Photograph

  • Lee Hyuk-Hae;Koshimiz Hajime
    • Journal of the Korean Institute of Landscape Architecture International Edition
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    • 제2호
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    • pp.102-108
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    • 2004
  • In the city of Asia like Seoul and Tokyo, aggregate power is poured into the city making which is suitable in new age. Large-scale re-development is active in various places as the present condition, As for the various East Asian cities, high-level utilization conversion of the land and high conversion of the building are advanced. As for these realities, the re-development is advanced in the situation that has not been clarified enough though it is true that green of the city has decreased. This research was aimed at the clarifying the allocation of greenery when proceeding with town planning projects by quantifying the possibility of allocating greenery in the form of rooftop landscaping in redeveloped areas. Moreover, the distribution of the green in the re-development region was calculated and the coexistence level of green space was calculated, The realities of a desirable green were clarified in the spectacle by understanding a sight and spatial continuousness in the green. In order to clarify the potentiality of roof greenery revaluating, the research was conducted by analyzing from aerial photographs, in Tokyo and Seoul, And the flow of the research was conducted by selection of research object area, taking pictures, acquisition of the aerial photography, rearrangement the data and the analysis. As a result, I was able to prepare a land vegetation coverage classification chart and obtain data pertaining to the level of urban and green tract of land for the researched cities of Tokyo and Seoul. By analyzing this data, we were able to indicate patterns of greenery unable to be obtained through data from ratio of vegetation coverage and ascertain the effectiveness of rooftop landscaping.

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집.배수용 투수성 폴리머 콘크리트 관의 농업 수리시설물의 현장적용 (Field Application of Permeable Polymer Concrete Pipe for Drainage)

  • 민정기;연규석;성찬용
    • 한국농공학회지
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    • 제45권6호
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    • pp.136-143
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    • 2003
  • This study is performed to evaluate performance of the developed pipe when using for underground drainage in fm land, the efficiency of the pipe is examined such as quantity of drainage, water temperature and other field performance in all weather condition. Results of this study, the higher permeability through wall of the pipe is achieved by making various size pores using open-graded aggregate. And in all weather conditions, permeable polymer concrete pipe perform much better than conventional perforated pipes. During rice farming period, quantity of drainage the permeable polymer concrete pipe is 1.25 time greater than conventional perforated pipes. Therefore, use of the permeable polymer concrete pipe is greater advantages when considering collecting and draining capacity compared with conventional perforated pipes.

Tolerance Analysis of Compact Imaging Spectrometer (COMIS) for a microsatellite STSAT3

  • Kim, Eun-Sil;Lee, Jun-Ho
    • 한국우주과학회:학술대회논문집(한국우주과학회보)
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    • 한국우주과학회 2008년도 한국우주과학회보 제17권2호
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    • pp.27.2-27.2
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    • 2008
  • The STSAT-3 satellite was initiated in October 2006 and will be launched into a lower sun-synchronous earth orbit (~700km) in 2010. COMIS takes hyperspectral images of 30m/60m ground sampling distance over a 30km swath width. The payload will be used for environmental monitoring, such as in-land water quality monitoring of Paldang Lake located next to Seoul, the capital of South Korea. An extensive sensitivity and error budget analysis of COMIS optical system have been performed. As way of estimating aggregate effects of all tolerances, a Monte Carlo simulation is used.

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Bottom Ash를 잔 골재 대체재로 사용한 콘크리트의 내구성에 관한 실험적 연구 (An Experimental Study on the Durability of Concrete using the Bottom Ash as a part of Fine Aggregate)

  • 최세진;이성일;정용;김양배;오복진;김무한
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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    • pp.19-24
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    • 2003
  • Recently, the by-product of coal ash has been increased by increase of consumption of electric power. So in view of environmental aspect, it is important to secure a reclaimed land and treatment utility for coal ash. This is an experimental study to compare and analyze the properties of high volume coal-ash concrete using the bottom ash. For this purpose, the mix proportions of concrete according to the replacement ratio of bottom ash(l0, 20, 35, 50%). And then air content, slump, compressive strength, durability test were performed. According to test results, it was found that the compressive strength of bottom ash concrete was similar to that of plain concrete(BA0). And the carbonation depth of bottom ash concrete increased as the replacement ratio of bottom ash.

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해사의 기본성질과 잔골재로서의 이용 방안에 관한 연구 (A Study on the Characteristics of Beach Sand as Fine aggregate of Concrete)

  • 황경구;전현우
    • 한국농공학회지
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    • 제18권4호
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    • pp.4265-4273
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    • 1976
  • 1. Fine aggregates of concrete are very important for the construction works and construction cost determination. Most of fine aggregates are from the river sand, but the amount of storage in the river side is steadily decreasing due to continuous construction works. Therefore, another source of fine aggregates is needed to meet increasied demand of sand. 2. Beach sand is a possible source of fine aggregates. But rust of steel bar is caused by CL-chemical of beach sand. Therefore, desalinization of beach sand is requested to get durable reinforced concrete. Economical methods of desalinization are as follows. (a) Flooding and drainage method. (b) Washing of beach sand with water supply and mixing. (c) Spreading of beach sand on the land and leaching by rain water for a few month. 3. Hardening of concrete with beach sand is accelerated due to salt, Thus early stage strength increase leads to make cracks. Also later stage strength decreases and durability becomes worse. By using appropriate admixture, the quality of concrete can be improved.

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산업부산물을 활용한 소파블럭 제조기술 개발 (Development of manufacturing technology of Wave Dissipating Block with industrial byproduct)

  • 한상묵;조명석;송영철
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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    • pp.129-132
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    • 2005
  • Reclamation coal ash, which is generated as a byproduct at a coal thermal power plant is not recycled but dumped into an ash landfill disposal site. Furthermore, various byproducts and wastes have been proposed for use from the point of reduction in the environmental load. Authors have started research to develope manufacturing technology of concrete mixture design method with large amount of land reclamation coal ash. In this study an optimum mix proportion design for utilizing the reclamation coal ash and containing copper slags as an aggregate for secondary concrete products such as a wave dissipating blocks was successfully developed.

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건설재료로서 하수슬러지 소각재 적정 대체율 도출에 관한 연구 (The Effects of Substitution Rate of Incinerated Sewage Sludge Ash on the Concrete Materials)

  • 김춘호;김남욱
    • 자원리싸이클링
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    • 제25권1호
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    • pp.10-15
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    • 2016
  • 최근 들어 환경보호나 국토의 효율적 활용 등의 측면에서 산업 각 분야에서 발생되는 각종의 산업부산물 및 폐기물 등의 유효하 고 효율적인 이용이 대두되고 있다. 본 연구에서는 갈수록 발생량이 증가하는 하수슬러지를 활용한 하수슬러지 소각재의 유효한 활용을 위하여 건설재료로서의 가능성을 평가하였다. 콘크리트 제작 후 평가항목은 압축강도, 중성화저항성 및 환경 평가인 용출시험으로 압축강도 및 중성화저항성에서 무첨가 콘크리트에 비해 만족스런 결과를 도출하였으며 용출시험 결과 역시 기준치를 모두 만족하는 결과를 나타냈다. 따라서 콘크리트용 잔골재로서 활용 가능성이 충분하며 적정 대체율은 약 10% 정도로 판단된다.

미고결 퇴적층의 암반분류와 재료원 평가 (Rock Classification and Aggregate Evaluation of Tertiary Unconsolidated Deposits)

  • 김성욱;이규환
    • 한국지반공학회논문집
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    • 제26권7호
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    • pp.25-36
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    • 2010
  • 동해안을 따라 미고결 퇴적층을 포함하는 신생대 제3기 퇴적분지가 소규모로 산재하여 분포한다. 이들 지역에서는 항만이나 대규모 단지 개발이 진행됨에 따라 양질의 매립재에 대한 수요가 증가하고 있다. 도로성토나 매립현장 주변에서 발생되는 유용암을 경제성을 고려하여 도로 성토재나 매립재로 사용되는 경우가 있으나 이러한 골재를 도로성토나 매립재로 사용하는 경우 품질기준의 적합성을 판단하기가 매우 어렵다. 미고결된 암석에 대한 실험 및 분석 결과, 적용된 실험방법에 따라 암석의 판정결과가 다르게 나타날 수 있음을 알 수 있었다. 따라서 제 3기 퇴적분지 지역과 같이 미고결 지층에서 암반분류와 지반정수 산정시에는 일반적으로 사용되는 암반분류 기준과는 다른 기준의 설정 및 적용이 필요한 것으로 판단되었다. 또한, 산성배수에 의한 환경영향에 대한 고려도 필요한 것으로 판단되었다.

한국의 모래 -품질평가- (Natural Sand in Korea - Quality Evaluation -)

  • 홍세선;이진영
    • 자원환경지질
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    • 제57권2호
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    • pp.185-204
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    • 2024
  • 이 연구는 국토교통부에서 수행하고 있는 골재자원조사를 통해 2023년까지 조사된 하천, 육상골재에서 천연모래의 약 4,800여 품질시험자료를 분석하여 국내 모래의 지질학적, 물리적, 화학적 특성을 평가하였다. 모래층을 포함하고 있는 국내 제4기 미고결 퇴적층의 평균심도는 10m 내외이다(최대 66m). 퇴적층 내에서의 모래층의 두께는 0.5m~4.0m 구간이 약 70%로 가장 우세하다. 모래층에서의 모래, 자갈, 점토는 대체로 60:20:10의 비율로 나타나며, 모래의 주구성광물은 석영, 사장석, K-장석이며, 부구성광물로는 백운모, 흑운모, 녹니석, 자철석, 녹염석 등이다. 석영은 약 45~75%, 사장석과 K-장석은 각각 약 5~20%, 그 외의 부구성광물은 10% 이내이다. 국내 모래의 평균 입도는 0.5mm~1.0mm로 모래시료의 약 44%가 이에 속한다. 1.0mm~1.5mm 입도는 전체모래의 19%, 0.125mm~0.25mm 입도는 전체모래는 약 9%를 점유하고 있다. 골재로 활용하기 위한 모래의 품질 기준에서 보면 흡수율, 안정성의 거의 모든 모래층에서 품질기준에 적합한 것으로 판정되며, 절대건조밀도는 약 66%가 적합하다.