• 제목/요약/키워드: weathering

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용해성 암석의 용식 진전에 대한 암석-광물학적 특성 연구 (Petro-mineralogical and Solubility Characterization in Soluble Rocks)

  • 정의진;윤운상;여상진;김정환;이근병;노영욱
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2002년도 봄 학술발표회 논문집
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    • pp.253-260
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    • 2002
  • Chemical weathering processes related with mineralogical characters and ground water condition are very essential engineering problems in soluble rock masses. Detailed geological mapping were performed and 8 samples were collected from the 2 formations including various rock faces to deduce the possibility of the limestone cavity formation and their mechanism. Petrological descriptions and various petro-mineralogical experiments such as XRD analysis, clay mineral analysis, absorptivity test, impurity analysis were conducted to evaluate the cavity making processes. Laboratory solubility test for rock specimen were also carried out under the strong acid (pH=1) condition. From the experimental data and geological mapping data, it is found that the formation of limestone cavities in limestones are strongly related with geological structures such as beddings, cleavages and the contents of impurities rather than CaCO$_3$contents. In case of dolomites, rock textures, grain size, amounts and types of clay minerals as well as geological structures are major controlling factors of cavity forming processes

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해상유출유의 분산모델링에 대한 응집효과 (The Effect of Coagulation for Dispersion Modelling of Spilled Oil)

  • 설동관
    • 한국해양공학회지
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    • 제14권2호
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    • pp.44-52
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    • 2000
  • The dispersion of surface oil is generally described as a break-up of oil slick into small oil droplets. These small droplets are subjected to turbulence and vertical circulation so that it can be entrained into subsurface. Sometimes they tend to be submerged into sea bottom permanently. The diameter of oil droplets is a critical parameter to determine their behavioral characteristics under water surface. At the same time the variations of droplet stability depends on the weathering of it. That is why the weathered oil has different mechanism from the unweathered one. The variability of physical properties of oil including viscosity and density contribute to interfere with effective separation of oil and emulsion droplets in water. Also in the presence of interactions among the droplets there are coalescing or coagulating effects on the dispersion process of droplets.

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대구지역 퇴적암의 풍화도판단 기술 연구 (A Study on the Geotechnical Assessment of Sedimentary Rock due to Weathering in Taegu area)

  • 김영수;김교원;허노영;예대호;이재호;최정호
    • 대한지질공학회:학술대회논문집
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    • 대한지질공학회 2001년도 정기총회 및 학술발표회
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    • pp.15-22
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    • 2001
  • 퇴적암의 풍화특성을 파악하기 위해서는 풍화과정을 지배하는 암석의 광물 조성과 화학성분에 대한 연구가 필요하다. 본 논문에서는 풍화정도에 따른 퇴적암의 특성을 고찰하기 위해서 대구지역에 분포하고 있는 퇴적암을 채취하여 화학 및 광물성분 분석과 시간경과에 따른 물리 및 역학특성 시험을 실시하였다. 퇴적암에 대한 풍화판정법은 시험결과 Parker의 풍화지수식이 잘 일치하였고 모암에 함유된 $Al_2$O$_3$, CaO, $Na_2$O, $K_2$O, MgO등의 화학성분과 조장석(Albite, Ab), 백운모(Muscovite, Ms), 마그네타이트(Magenetite, Mt)등의 광물성분이 풍화와 밀접한 관계가 있었으며, 또한 암석의 풍화정도와 공학적 성질에 대한 상관관계식을 제안하였다.

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거창 분지와 가조 분지에 발달한 화강암 사질 풍화층의 화학적 풍화 양상 - CIA분석을 중심으로 (Chemical Weathering Characteristics and CIA of Granitic Grus Developed in Geochang and Gajo Basin, Korea)

  • 김영래;기근도
    • 한국지형학회지
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    • 제24권2호
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    • pp.41-49
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    • 2017
  • From the results of the CIA analysis (A-CN-K and A-CNK-FM ternary diagram), we concluded that granitic grus experienced low chemical alteration and contains plenty of sandy material The chemical alteration of Geochang and Gajo Basin advanced further than that of Yeongju-Bonghwa basin, but does not come to spatial differentiation as Chuncheon Basin. The weathered mantles of inner hills in the basin exhibit very weak alteration, and there is little spatial differentiation of chemical alteration between footslope of mountains, footslope hills. Most of hills are still in incipient weathering stage and have plenty of sandy materials. Therefore the chemical characteristics of granitic hills in Geochang and Gajo basin show that granitic weathered mantles are not saprolite formed by alteration but may be just grus (sandy weathered mantles).

풍화 손상 및 단면 결손에 따른 문화재 불단의 구조 안전성 평가 (Evaluation of Structural Safety of Cultural Property Altar due to Weathering Damage and Sectional Defection)

  • 이가윤;이성민;이기학
    • 한국공간구조학회논문집
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    • 제18권4호
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    • pp.23-30
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    • 2018
  • The purpose of this study is to evaluate the structural safety of cultural altar since its bearing capacity has been questioned due to weathering damages and sectional defections. This evaluation process consists two stages; which the first is field investigation and the second is structural modeling and analysis. Based on field investigation, all of the structural members supporting the altar were carefully examined and all the findings were accounted for the development of the structural modeling using the Midas computer program. Using a 3D scanner, the weight of the Buddha statue was applied to the structural modeling. Then, according to the allowable stress design method of KBC2016, the structural safety was evaluated. Based on this result, replacements of several structural members were recommended to increase the structural safety and value of cultural property.

화강암 분지를 흐르는 미호천의 지형학적 특색 (Geomorphological Characteristics of the Miho Stream Flowing through a Granitic Plain, South Korea)

  • 김영래
    • 한국지형학회지
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    • 제28권3호
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    • pp.1-11
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    • 2021
  • The drainage area of the Miho stream is composed of granitic basins, gneissic and sedimentary mountains. 80 percent of the Miho stream flows through the Jincheon basin and the Cheongju inner-plain within the Daebo granite belt. Because the deep weathering of granitic hills provides a large amount of sands to the streams, there are wide floodplains with thick alluvium developed in the basin and plain. The thickness of the alluvium is 5~10m and the width of the floodplains is 2~2.5km. In the basin outlet area where a stream passes through the mountain canyon, wide floodplains and deep alluvium are developed in other riverside. The Miho stream is a sand-gravel channel flowing through the Cheongju inner-plain with wide floodplains and deep alluvium formed by deep weathering of granite.