• 제목/요약/키워드: drainage method

검색결과 894건 처리시간 0.026초

쇄석말뚝으로 보강된 연약지반의 침하거동 (Settlement Behavior of Soft Ground Reinforced by Stone Columns)

  • 신방웅;배우석
    • 한국지반환경공학회 논문집
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    • 제1권1호
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    • pp.27-33
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    • 2000
  • 쇄석말뚝 공법은 다져진 자갈, 폐석, 쇄석 등을 이용하여 느슨한 사질지반이나 연약점성토 지반을 개량하는 공법으로 일반적으로 말뚝은 70%이상의 치환율로 실트질 점토에 시공되어 지지력을 증진시키는 공법이나 말뚝을 배수층으로 압밀에 의한 점성토의 지반의 강도 증가를 전제로 치환율을 30% 이하로 억제하는 저치환 공법의 효율에 관한 연구가 진행되고 있다. 본 연구에서는 쇄석말뚝의 치환율에 따른 단일 등가원주 모형 실험을 실시하여 쇄석말뚝이 연약지반의 압밀거동에 미치는 영향을 분석하였다. 실험결과 치환율의 증가에 따른 침하감소효과와 침하저감계수를 산정하였으며 복합지반의 압밀시간 단축을 확인하였다. 또한, 복합지반에 대한 이론식을 이용한 장기침하량 예측을 통해 보강지반의 침하억제 경향을 평가하고 베인전단시험을 통해 복합지반의 강도증가특성을 확인하였다.

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확정론적 모의기법에 의한 도시유출 해석에 관한 연구 (A Study on urban runoff by deter ministic simulation techniques.)

  • 이은영;강관원
    • 물과 미래
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    • 제15권3호
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    • pp.37-47
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    • 1982
  • 본 연구는 확정론적 모의기법 중 영국도로시험연구소에서 개발한 R.R.L법을 포장 지역이 넓은 인천에 위치한 간석동 아파트에 적용하여 그 실용성을 검토하였다. 인천지방의 전체적이고 합리적인 결과를 얻기 위하여 과거 28년간 누가우량 곡선에서 얻은 10mm 이상 되는 강우 450개를 5분 간격으로 읽어 확률빈도통계인 HUFF의 사분위법을 이용 확률빈도백분율곡선을 얻어 R.R.L법에 적용하였다. 인천지방의 확률빈도백분률 곡선은 제2 구간이 전체의 43.2%를 나타내므로 설계우량의 우량주상도는 제을구간에서 추출함이 바람직하다.

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USGA 공법으로 조성된 그린의 토앙물리성과 Bentgrass의 생육 (Turfgrass Establishment of USGA Putting Greens Related with Soil Physical Properties)

  • 권동영;이정호;이동익;주영규
    • 아시안잔디학회지
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    • 제19권2호
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    • pp.95-102
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    • 2005
  • USGA green specification is currently accepted in construction method of Korea. This study was carried out to find the factors influencing growth of turfgrass associated with soil physical properties of soil root-zone on golf green constructed with USGA method. Three putting greens in poor turfgrass and one in good turfgrass condition were selected for investigation on one golf course site at mid-South Korean peninsula. Soil hardness, moisture content, root length, and turf density were measured on-site greens, and soil physical properties and soil chemical properties also analyzed in laboratory. As a result of on-site surveys and soil physical tests in laboratory, soil physical properties were most important factors which influenced on turfgrass growth at tested greens. The results of soil particle analysis on green No. 2, in good turf condition, matched USGA sand particle recommendations. But those greens such as Nos. 1, 11 and 16, in poor putting greens, showed high soil compaction and improper soil particle distribution. Those factors created low leaf density, poor root depth, and higher moisture content compared with lower part of topsoil. Such phenomena caused inadequate turfgrass growth with soil hardening associated with poor drainage. Therefore, declines of soil physical properties associated with improper particle distribution caused a major factor influencing on turfgrass growth in golf green. Adequate test of soil particle analysis by USGA specification and proper construction method followed by adequate turf maintenance should be performed to obtain optimal turf quality on putting green.

"황제내경(黃帝內經)"의 구침(九鍼)과 관침(官鍼) 개념에 대한 소고(小考) (A Study on the Gu-chim(九鍼) and Guan-chim(官鍼) of "Hwangje-Naegyeong(黃帝內經)")

  • 백유상;김도훈
    • 대한한의학원전학회지
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    • 제21권2호
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    • pp.101-112
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    • 2008
  • Generally, we regard the concept of Guchim(九鍼) in "Naegyeong(內經)" as the a generic term of acupuncture means of nine kinds of forms and usages. However, it also contains the meaning of methods and transcriptures of acupuncture. The diversity of Guchim reflects that it has a high level diagnosis and treatment based on overall analysis of symptoms and signs. And among the treatments, reinforcing and reducing methods are prominent. The treatments of reinforcing and reducing methods, usually use Hochim(毫鍼), the filiform needle. The focus of Guchim, in reinforcing and reducing of Gi(氣), is reinforcing and reducing by way of drainage of Gi. And it mainly deals with diseases of Gi. From the research of the philosophic background of the number Nine in Chinese philosophy, number nine symbolizes the posterior and space, as number one symbolizes apriority and time. In this circumstances, Guchim became the supreme method of acupuncture. The concept of Gwanchim(官鍼), standardized needle in "Naegyeong" also expresses the Guchim as theory and skill in standardized traditional medicine. The period of materialization of Guchim and Gwanchim lies in from the era of Jeonguk[戰國時代, the age of civil wars] to Han dyansty[漢代], when the "Naegyeong" made a synthesis of the medicine in those days, as the society unified politically and ideologically. In this process, Guchim was sublimated in method of acupuncture which contained absolute authority.

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미국 인디아나주 남서부 Friar Tuck 폐탄광에 대한 환경평가 및 최종 복구설계 (Environmental Evaluation and Final Reclamation Design for the Friar Tuck Abandonded Coal Mine Site, Southwestern Indiana, U.S.A.)

  • 최정찬
    • 지질공학
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    • 제6권2호
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    • pp.65-81
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    • 1996
  • Friar Tuck 폐광산은 인디아나주 남서부 Tuck Greene-Sullivan 군 경계에 위치하고 있다. 현재 진행중인 복구작업이 시행되기 전, Friar Tuck 광상은 인디아나주 내에서 가장 규모가 크고 환경오염상태가 심각한 폐탄광중의 하나였다. 직접 식물재배법이 tailing ponds에 적용되었다. 버럭더미는 산성수의 오염을 막고 토양이 외부로 흘러 나가는 것을 방지하기 위해 표면을 고른 후 토양오염이 비교적 덜 된 흙으로 덮고 농업용 석회석, 화학비료 및 퇴비를 뿌려 풀 종자를 심었다. 사면의 침식방지를 최소화 하기 위하여 terrace, diversion ditch, 및 gabion structures가 설치도었다. 산성수 처리를 위하여 실내 및 광산현장에서 인회석을 이용한 새로운 방법이 실험되었다. 인회석은 산성수 본래의 pH를 유지하면서 철 및 알루미늄을 효과적으로 제거하였다. 광산폐기물에서 파생되는 산성수 내의 철 및 알루미늄의 농도가 높은 경우에도 이 방법을 사용할 수 있을 것으로 사료된다.

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간극수압 소산경향을 고려한 자가굴착식 프레셔메터로부터의 수평압밀계수 결정법 (Determination of Horizontal Coefficient of Consolidation from the Self-boring Pressuremeter Holding Test by Considering Pore Pressure Dissipation Trend)

  • 김영상
    • 한국지반공학회논문집
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    • 제20권3호
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    • pp.151-159
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    • 2004
  • 본 논문에서는 자가굴착식 프레셔메터 시험의 변형을 유지시험(strain holding test)에서 관측된 소산시험 결과의 초기 소산경향으로부터 점성토 지반의 수평압밀계수를 추정하기 위한 최적화기법의 적용에 대하여 기술하였다. 프레셔메터의 확장으로 인한 초기 과잉간극수압의 분포는 Randolph. & Wroth(1979)의 해석적 해(analytical solution)를 이용하여 지반의 강성지수의 함수로 모사되었으며 연속된 간극수압 소산과정까지 전과정이 모사되었다. 제안된 기법에서는 이를 소산곡선과 정규화 된 관측 소산곡선이 초기 50% 범위에서 소산경향이 가장 일치하도록 하는 수평압밀계수를 최적화기법을 이용하여 결정하였다. 제안된 기법을 김제와 양산에서 수행된 기존의 자가굴착식 프레셔메터 연구결과의 해석에 적용하였으며 제안된 방법으로 얻어진 수평압밀계수를 기존의 연구결과, 실내 및 원위치 시험결과와 비교하였다. 연구결과 제안된 방법은 피에조콘 소산시험과 매우 일관성있게 일치하는 수평압밀계수를 제공할 뿐 아니라 부분배수가 발생하는 지점에서도 간극수압 소산경향을 반영함으로 인해 보다 적절한 수평압밀계수를 결정할 수 있음을 알았다.

DEM을 기반으로 한 흐름방향 모의기법에 따른 배수구조의 변동성 해석 (Analysis of Variation for Drainage Structure with Flow Direction Methods on the Basis of DEM)

  • 박혜숙;김주철
    • 한국물환경학회지
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    • 제34권4호
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    • pp.391-398
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    • 2018
  • The main purpose of this study is to suggest and recommend the more reliable flow direction methods within the framework of DEM and power law distribution, by investigating the existing methodologies. To this end SFD (single flow direction method), MFD (multiple flow direction method) and IFD (Infinite flow direction method) are applied to analyze the determination of a flow direction for the water particles as seen in the Jeonjeokbigyo basin, and then assessed with respect to the variation of flow accumulation in that region. As the main results revealed, the study showed the different patterns of flow accumulation are found out from each applications of flow direction methods utilized in this study. This brings us to understand that as the flow dispersion on DEM increases, in this case the contributing areas to the outlet grow in sequence of SFD, IFD, MFD, but it is noted that the contribution of individual pixels into outlet decreases at that time. In what follows, especially with the MFD and IFD, the result tends to make additional hydrologic abstraction from rainfall excess, as noted due to the flow dispersion within flow paths on DEM. Based on the parameter estimation for a power law distribution, which is frequently used for identify the aggregation structure of complex system, by maximum likelihood flow accumulation can be thought of as a scale invariance factor. In this regard, the combination of flow direction methods could give rise to the more realistic water flow on DEM, as revealed through the separate flow direction methods as utilized for dispersion and aggregation effects of water flow within the available different topographies.

Fuzzy-based multiple decision method for landslide susceptibility and hazard assessment: A case study of Tabriz, Iran

  • Nanehkaran, Yaser A.;Mao, Yimin;Azarafza, Mohammad;Kockar, Mustafa K.;Zhu, Hong-Hu
    • Geomechanics and Engineering
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    • 제24권5호
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    • pp.407-418
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    • 2021
  • Due to the complexity of the causes of the sliding mass instabilities, landslide susceptibility and hazard evaluation are difficult, but they can be more carefully considered and regionally evaluated by using new programming technologies to minimize the hazard. This study aims to evaluate the landslide hazard zonation in the Tabriz region, Iran. A fuzzy logic-based multi-criteria decision-making method was proposed for susceptibility analysis and preparing the hazard zonation maps implemented in MATLAB programming language and Geographic Information System (GIS) environment. In this study, five main factors have been identified as triggering including climate (i.e., precipitation, temperature), geomorphology (i.e., slope gradient, slope aspect, land cover), tectonic and seismic parameters (i.e., tectonic lineament congestion, distribution of earthquakes, the unsafe radius of main faults, seismicity), geological and hydrological conditions (i.e., drainage patterns, hydraulic gradient, groundwater table depth, weathered geo-materials), and human activities (i.e., distance to roads, distance to the municipal areas) in the study area. The results of analyses are presented as a landslide hazard map which is classified into 5 different sensitive categories (i.e., insignificant to very high potential). Then, landslide susceptibility maps were prepared for the Tabriz region, which is categorized in a high-sensitive area located in the northern parts of the area. Based on these maps, the Bozgoosh-Sahand mountainous belt, Misho-Miro Mountains and western highlands of Jolfa have been delineated as risk-able zones.

연직배수공법에 있어서 제강슬래그의 재활용을 위한 투수성 연구 (Considerations of Permeability of Converter Slag for Recycling in vertical drainage method)

  • 이광찬;정규향;김영남;이문수
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2000년도 연약지반처리위원회 학술세미나
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    • pp.93-112
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    • 2000
  • The permeability of converter slag, replacing material of sand mat on improving soft clay foundation, was evaluated in the laboratory. The effects of grain size, flow water time and aging were investigated using sea and fresh water. Converter slag being submerged with fresh water, the coefficients of permeability in A and B samples less than 10mm grain sizes were measured as 6.52${\times}$10$\^$-2/cm/sec and 5.99${\times}$10$\^$-1/cm/sec, while changed as 1.88${\times}$10$\^$-2/cm/sec, 3.86${\times}$10$\^$-1/cm/sec under sea water condition. Also, the condition of turbulent flow may exit and was experimentally identified from the relationship between hydraulic gradient and seepage velocity. After 180 days on using sea water, the coefficients of permeability of sample A and B samples decreased ten times smaller than those initial values. And after that time continually decreased as for till 360 days. The reduction of permeability coefficient was considered to influence filled with voids in high-calcium quicklime(CaO). However, in-situ coefficient of permeability was practically satisfactory.

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연직배수공법에 있어서 제강슬래그의 재활용을 위한 투수성 연구 (Considerations of Permeability of Converter Slag for Recycling in vertical drainage method)

  • 이광찬;정규향;김영남;이문수
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2000년도 연약지반처리위원회 학술세미나
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    • pp.12-31
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    • 2000
  • The permeability of converter slag, replacing material of sand mat on improving soft clay foundation, was evaluated in the laboratory. The effects of grain size, flow water time and aging were investigated using sea and fresh water. Converter slag being submerged with fresh water, the coefficients of permeability in A and B samples less than 10mm grain sizes were measured as 6.52${\times}$10$\^$-2/cm/sec and 5,99${\times}$10$\^$-1/cm/sec, while changed as 1,88${\times}$10$\^$-2/cm/sec, 3.86${\times}$10$\^$-1/cm/sec under sea water condition. Also, the condition of turbulent flow may exit and was experimentally identified from the relationship between hydraulic gradient and seepage velocity. After 180 days on using sea water, the coefficients of permeability of sample A and B samples decreased ten times smaller than those initial values. And after that time continually decreased as for till 360 days. The reduction of permeability coefficient was considered to influence filled with voids in high-calcium quicklime(CaO). However, in-situ coefficient of permeability was practically satisfactory.

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