• 제목/요약/키워드: ground loss quantity

검색결과 13건 처리시간 0.019초

선행하중 재하시 지반손실 감소효과에 관한 연구 (A study on reduction effects of the ground loss in pre-loading)

  • 김봉유;조남준
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2005년도 춘계 학술발표회 논문집
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    • pp.224-231
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    • 2005
  • The ground excavation causes the deformation of the ground where the neighborhood structure is located. The ground deformation result in the vertical settlement of the neighborhood structure as well as the horizontal displacement of the temporary earth retaining structures. The decreased volume of the soil due to the ground settlement is defined as 'the ground loss quantity' or 'the ground loss'. When excavation is performed nearby existing structures, retaining walls should be designed and constructed to minimize the ground loss. Among various methods for reducing the ground loss, this study introduces the pre-loading method which has been recently developed. The reduction effect of the ground loss by pre-loading has been found to be larger as using a wall with relatively smaller rigidity.

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저장량과 환기구크기가 움저장 생강의 저장성에 미치는 영향 (The Effects of Storage Amount and Ventilator Size on the Quality of Ginger During Cellar Storage)

  • 최윤희;이상복
    • 한국식품저장유통학회지
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    • 제2권1호
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    • pp.195-202
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    • 1995
  • An experiment was conducted to develop the simple methods of ginger storage which decrease the weight reduction and maintain good quality of ginger during the cellar storage. The stored boxes with volume of 0.03㎥ and ventilator diameter of 3, 4, 5cm was hurried under the ground(60, 80, 100cm) in the green house. During the cellar storage at the 100cm depth the average temperature and relative humidity in the stored box were remained in 11.7~16.3$^{\circ}C$ and 73%, respect. The higher storage amount and smaller size of ventilator size increased the CO2 concentration in the stored box, and the concentration in the stored box with 50% storage quantity rate and 3cm ventilator diameter size was more than 10% for about 2 months from early Feburary. The decay rate of ginger during the cellar storage increased with higher amount of storage quantity and smaller size of ventilator. The CO2 concentration was low and remained relatively constant with the deeper location of stored box under the ground, and the decay rate was lower in the deeper stored box. Germination rate increased with the deeper location of stored box, and with the lower storage quantity and larger ventilator size. The germination rate was low in the higher decay rate box. Weight loss, total sugar and moisture contents of ginger were decreased, while crude fiber and ash were increased during the storage.

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단열골재 개발을 통한 동토방지 기술개발에 관한 연구 (A Study on the Development Lightweight Aggregate using Recycled-Paint for Reduction in Freezing Ground)

  • 문종욱;백민호
    • 한국방재학회 논문집
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    • 제10권4호
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    • pp.47-54
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    • 2010
  • 지정폐기물인 폐페인트를 이용한 단열골재 개발을 위한 자료를 제시하기 위하여 이를 위한 실험으로 함수비, 진밀도, 액성한계, 소성한계, 마모감량, 모래당량, 체가름 시험을 진행하였다. 함수비 시험은 80:20의 배합이 1.4이고, 쇄석 골재만 사용한 것은 1.0으로 폐페인트 단열골재의 용적비가 증가하면서 함수비의 증가도 많았다. 또한, 진밀도 시험은 혼입율의 증가에 따라 점점 상승하였고, 흡수율도 증가하였다. 이는 골재와 폐페인트의 특성상 발생되는 공극분포의 차이로 인한 현상으로 판단된다. 모래당량과 마모감량 실험에서는 마모감량은 쇄석골재만 사용한 경우는 13.5이고 20% 혼입한 경우는 14.4로 증가하지만, 이는 단열골재의 약한 조직으로 인한 현상이라 판단된다. 이러한 실험으로 볼 때, 도로공사 시방서의 동상방지층은 모래당량 20, CBR 10으로 만족하도록 규정하고 있어 본 실험은 전 배합에서 모두 품질기준에 만족하는 결과를 보였다. 현재 폐페인트는 단순 매립용하거나, 소각 처리되는 현 실정에서 골재로 활용할 수 있게 됨으로써 천연골재의 부족이나 자원의 낭비를 해소할 수 있을 것으로 파악된다. 기존의 자갈보다 단열효과가 뛰어나고, 가벼우며, 단단한 단열골재를 사용함으로써 재활용이 활발할 것으로 예상된다.

고가 구조물 건설에 따른 일조권 분석 (Analysis of the right to sunshine for elevated structure construction)

  • 강기수;김상석;양승태;강인준
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2004년도 춘계학술발표회논문집
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    • pp.485-490
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    • 2004
  • Recently, distribution transfer velocity was extremely lowered by high supply rate of vehicle and low road rate. Therefore expansions of transfer network these were subway, road and railway to recover competitive power as a reform measure of physical distribution traffic were become preference previous subject. For reason of that, an expansion of transfer network is meeting competitive power as selected an elevated road in the ground road network that condition of location calm and get out of the existing urban than the underground road to connect oversensitive a large city and expanded small and medium satellite town. In the meantime, while elevated structures construct, they go through the civilian residential section, agriculture land, etc. The consequence is that it raises a vibration, noise, dust, an infringement of the right to a view and an infringement of the right to a sunshine. In this study, we analyzed Quantitatively sunshine quantity with building 3D simulation model of civil structure. Therefore, we present as planning data to reduce a civilian appeal for dispute of the right to sunshine and an economic and time loss between the government and construction company In addition to that, for the standard of the standard plan of usable sunshine quantity program in the practical business, the building of convenient user interface will be the project to be done.

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도라지의 Ca.Mg.K.Na.P와 이들의 수침(水浸)과 Boiling에 따른 변화(變化) (Study on the Changes in Ca.Mg.K.Na and P Contents of the Platycodon Graucum Nakai by Water Immersion and Boiling)

  • 이월형;이만정
    • 한국식품영양과학회지
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    • 제3권1호
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    • pp.35-41
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    • 1974
  • The experiment attempted to detect the loss of mineral substances in the crude herb, especially for the Platycodon graucum Nakai after removal of its acrid flavor. The results obtained are summarized as follows: 1. The quantity of the mineral substance was K Ca P Mg and Na in orders. The above substances were more prevalent in the part of the plant above the ground than the plant below the ground, however Na remained the same in both parts of the plant. 2. As a result of water immersion, in order to clear away the acrid flavor, the one day exudate showed that K was highest in amount and in the others there was no significant difference. There was a slight increase, however, in the amount of Ca K Mg P and Na because of exudation on the 3rd and 5 th days. 3. The amount of the exudate was increased by boiling rather than simple water immersion, but the amount of Ca was decreased.

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Incorporating ground motion effects into Sasaki and Tamura prediction equations of liquefaction-induced uplift of underground structures

  • Chou, Jui-Ching;Lin, Der-Guey
    • Geomechanics and Engineering
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    • 제22권1호
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    • pp.25-33
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    • 2020
  • In metropolitan areas, the quantity and density of the underground structure increase rapidly in recent years. Even though most damage incidents of the underground structure were minor, there were still few incidents causing a great loss in lives and economy. Therefore, the safety evaluation of the underground structure becomes an important issue in the disaster prevention plan. Liquefaction induced uplift is one important factor damaging the underground structure. In order to perform a preliminary evaluation on the safety of the underground structure, simplified prediction equations were introduced to provide a first order estimation of the liquefaction induced uplift. From previous studies, the input motion is a major factor affecting the magnitude of the uplift. However, effects of the input motion were not studied and included in these equations in an appropriate and rational manner. In this article, a numerical simulation approach (FLAC program with UBCSAND model) is adopted to study effects of the input motion on the uplift. Numerical results show that the uplift and the Arias Intensity (Ia) are closely related. A simple modification procedure to include the input motion effects in the Sasaki and Tamura prediction equation is proposed in this article for engineering practices.

지반의 동결저감 대책기술을 수립하기 위한 클링커애쉬 인공경량골재 개발에 관한 연구 (A Study on the Development Lightweight Aggregate using Clink Ash for Reduction in Freezing Ground)

  • 문종욱
    • 한국화재소방학회논문지
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    • 제23권6호
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    • pp.116-125
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    • 2009
  • 클랭커 애쉬를 이용한 인공 경량 골재 개발을 위한 자료를 제시하기 위하여 이를 위한 실험으로 함수비, 진밀도, 액성한계, 소성한계, 마모감량, 모래당량, 체가름 시험을 진행하였다. 함수비 시험은 80 : 20의 배합이 1.4이고, 쇄석 골재만 사용한 것은 1.0으로 클링커애쉬 경량골재의 용적비가 증가하면서 함수비의 증가도 많았다. 또한, 진밀도 시험은 혼입율의 증가에 따라 점점 상승하였고, 흡수율도 증가하였다. 이는 폴리스티렌 비드의 특성상 클링커애쉬와 경량골재 사이의 공극율의 증가로 나타난 현상으로 판단된다. 모래당량과 마모감량 실험에서는 마모감량은 쇄석골재만 사용한 경우는 13.5이고 20% 혼입한 경우는 14.4로 증가하지만, 이는 경량골재의 약한 조직으로 인한 현상이라 판단된다. 이러한 실험으로 볼 때, 도로공사 시방서의 동상방지층은 모래당량 20, CBR 10으로 만족하도록 규정하고 있어 본 실험은 전 배합에서 모두 품질기준에 만족하는 결과를 보였다. 현재 클링커 애쉬는 단순 매립용 골재나, 매립으로 폐기하는 현실정에서 골재로 활용할 수 있게 됨으로써 천연골재의 부족이나 자원의 낭비를 해소할 수 있을 것으로 파악된다. 기존의 자갈보다 단열효과가 뛰어나고, 가벼우며, 단단한 경량골재를 사용함으로써 재활용이 활발할 것으로 예상된다.

알칼리 자극제를 혼입한 고로슬래그 모르타르의 건조수축 특성에 관한 실험적 연구 (An Experimental Study on the Properties of Drying Shrinkage for Alkali-Activated Slag Mortar)

  • 천정환;김재훈;지남용
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2006년도 춘계학술논문 발표대회 제6권1호
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    • pp.97-100
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    • 2006
  • This paper report the result of the investigation on the properties of drying shrinkage for alkali-activated slag mortar in different relative humidity Commonly we know that drying shrinkage means lost more moisture but the mechanism of drying shrinkage of alkali activated slag mortar is not entirely due to the quantity of weight loss of water from mortar. pore size distribution and the calcium silicate hydrate gel characteristics have a critical influence on the magnitude of drying shringkage to alkali activated slag mortar. For this investigation, Ca(OH)2, Na2SiO4 were as alkali activator with 5 dosages(6%, 9%, 12%, 15%, 20%) and curing condition were three different relative humidity(35%, 65%, 95%) at $20{\pm}3^{\circ}C$

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하중판을 이용한 미끄러짐 측정기의 동력학적 특성 평가 (Evaluation of Dynamic Characteristics of Slipmeters with Force Platform)

  • 김정수
    • 한국안전학회지
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    • 제27권5호
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    • pp.1-8
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    • 2012
  • The purpose of this study were to evaluate the dynamic characteristics of the portable slipmeters with respect to actual slipping and to compare their output with those of force platform. The selected slipmeters were commonly used devices for slipperiness measurement in situ floors. Their output quantity represented force (BOT-3000), loss of energy(British pendulum striker) and angle of inclination(English XL). The validity of these devices was studied with respect to actual slipping using a force platform. The precision of these devices was also evaluated with force platform. Based on dynamics of human subject behavior when slipping during normal walking, the all devices tested in this study showed poor performances: low built up ratio, low normal pressure, and long contact time prior to slip. Nevertheless, their results reasonably correlated with those calculated from the ground reaction forces generated by the operation of the selected slipmeters on the force platform although the absolute values of COF from these three devices could be quite different. Also the results showed good repeatability under the some test conditions.

Site Characteristics and Carbon Dynamics of the Gwangneung Deciduous Natural Forest in Korea

  • Lim, Jong-Hwan;Shin, Joon-Hwan;Kim, Choonsig;Oh, Jeong-Soo
    • 한국제4기학회지
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    • 제17권2호
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    • pp.163-163
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    • 2003
  • The study area, Kwangneung Experiment Forest (KEF) is located on the west-central portion of Korean peninsula and belongs to a cool-temperate broadleaved forest zone. At the old-growth deciduous forest near Soribong-peak (533.1m) in KEF, we have established a permanent plot and a flux tower, and the site was registered as a KLTER site and also a KoFlux site. In this study, we aimed to present basic ecological characteristics and synthetic data of carbon budgets and flows, and some monitoring data which are essential for providing important parameters and validation data for the forest dynamics models or biogeochemical dynamics models to predict or interpolate spatially the changes in forest ecosystem structure and function. We made a stemmap of trees in 1 ha plot and analyzed forest stand structure and physical and chemical soil characteristics, and estimated carbon budgets by forest components (tree biomass, soils, litter and so on). Dominant tree species were Quercus serrata and Carpinus laxiflora, and accompanied by Q. aliena, Carpinus cordata, and so on. As a result of a field survey of the plot, density of the trees larger than 2cm in DBH was 1,473 trees per ha, total biomass 261.2 tons/ha, and basal area 28.0 m2/ha. Parent rock type is granite gneiss. Soil type is brown forest soil (alfisols in USDA system), and the depth is from 38 to 66cm. Soil texture is loam or sandy loam, and its pH was from 4.2 to 5.0 in the surface layer, and from 4.8 to 5.2 in the subsurface layer. Seasonal changes in LAI were measured by hemispherical photography at the l.2m height, and the maximum was 3.65. And the spatial distributions of volumetric soil moisture contents and LAIs of the plot were measured. Litterfall was collected in circular littertraps (collecting area: 0.25m2) and mass loss rates and nutrient release patterns in decomposing litter were estimated using the litterbag technique employing 30cm30cm nylon bags with l.5mm mesh size. Total annual litterfall was 5,627 kg/ha/year and leaf litter accounted for 61% of the litterfall. The leaf litter quantity was highest in Quercus serrata, followed by Carpinus laxiflora and C. cordata, etc. Mass loss from decomposing leaf litter was more rapid in C. laxiflora and C. cordata than in Q. serrata litter. About 77% of C. laxiflora and 84% of C. cordata litter disappeared, while about 48% in Q. serrata litter lost over two years. The carbon pool in living tree biomass including below ground biomass was 136 tons C/ha, and 5.6 tons C/ha is stored in the litter layer, and about 92.0 tons C/ha in the soil to the 30cm in depth. Totally more than about 233.6 tons C/ha was stored in DK site. And then we have drawn a schematic diagram of carbon budgets and flows in each compartment of the KEF site.

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