• 제목/요약/키워드: Settlement

검색결과 3,814건 처리시간 0.027초

Effects of Canopy and Settlement Density on the Performance of the Brown Seaweed Fucus serratus Germlings

  • Choi, Han-Gil
    • Animal cells and systems
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    • 제7권4호
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    • pp.295-301
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    • 2003
  • Effects of the settlement density of germlings and canopy on settled germlings of Fucus serratus were investigated on the rocky shore of the Isle of Man. The survival of transplanted germlings was mainly determined by parent canopy rather than by initial settlement density of germlings. However, germling growth was greater at low density than at high density and enhanced by canopy removal. Recruitment by natural propagules was stimulated at high settlement density and maximal recruits occurred on caged slides under the canopy. On the experimental slides, tiny snails and sedimentation were ,found. The number of snails was positively related with the settlement density of germ lings indicating that they fed the germlings. Sedimentation and snail number were greater with canopy removal treatments than in canopy intact ones. These indicate that ,canopy sweeping gives benefits to germlings by removing sediment from substrata and protecting them from herbivores. In conclusion, the survival of settled F. serratus germlings is mainly determined by canopy sweeping and their growth is retarded in the presence of a canopy and at high settlement density.

천층터널 쉴드TBM에서 역해석을 이용한 Gap Parameter 및 지표침하 영향범위에 대한 연구 (A study on Gap Parameter and Influence Area of Ground Settlement Using Back Analysis Constructed by Shield TBM with Shallow Depth)

  • 고성일;권성주;황창희;김상인;추석연
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2011년도 춘계학술대회 논문집
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    • pp.1509-1518
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    • 2011
  • Shield TBM tunneling method has been getting the spotlight for urban tunneling. It can be minimized the civil complaint during construction and possible safe tunneling. But the settlement has occurred inevitably due to characteristics of shield TBM equipment. For this reason, the civil complaint can occur in urban areas when tunnel with shallow depth passes through neighboring building or residential area. In this study, the occurrence factors of settlement according to shield TBM tunneling and the tendency of ground settlement by strata condition had analyzed. It is suggested that the practical settlement estimation method and minimizing method of ground settlement under simultaneous backfill grouting condition through measurement results and back analysis data using gap parameter.

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농촌마을 개발제도의 변천과 농촌마을에 대한 영향 (Changes in Rural Settlement Development System and its Effects on the facilities & houses of Village settlements in Rural area)

  • 조준범;최찬환
    • 한국농촌건축학회논문집
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    • 제1권2호
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    • pp.109-117
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    • 1999
  • The purpose of the study is to evaluate the Rural Settlement Development(RSD) driven by government in historical view, and its effects on the facilities and houses of rural village in the country. Through the study, we have come to the results that the major concerns of the RSD projects since 1950s has been transferred to as following. First, the reformation of inter-facility; dressing room, kitchen, bath-house, etc of rural houses, from that of outer facility; roof, fence and etc. Secondly, the substantial objects of the projects of village settlement improvement have been changed from partial reformation of individual houses, public facilities, etc early, to comprehensive reformation by master plan for village settlement recently. Lastly, those have been established that the process of planning village settlement available to carry out landuse division and the various program for village improvement, based on its inherent circumstances.

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건조효과를 고려한 준설매립토의 압밀거동 (Behaviour of Consolidation in Dredged and Reclaimed Soil Considering the Effect of the Desiccation)

  • 유남재;박병수;이명욱;이주원
    • 산업기술연구
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    • 제20권A호
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    • pp.93-100
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    • 2000
  • This research is to investigate the self-weight consolidation settlement and desiccation shrinkage settlement of soft marine dredging clay by performing numerical and experimental works. Large column test were carried out investigate the consolidation settlement considering effect of the self-weight and desiccation shrinkage, and centrifuge model test was also carried out investigate self-weight consolidation settlement. Results of centrifuge model and large column experiments about changes of settlement with time were analyzed by using the numerical technique of explicit finite difference method considering effect of the self-weight and desiccation based on the finite strain consolidation theory. Centrifuge model test results were in relatively good agreements with analyzed results in terms of self-weight consolidation settlement with time. Large column test results showed quite different values from the numerically estimated one, carried by experimental conditions.

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계곡형상을 고려한 CFRD의 축조 중 침하량 예측 (Settlement Estimation of CFRD Considering Valley Shape During Construction Period)

  • 박한규;김용성;임희대
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2005년도 지반공학 공동 학술발표회
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    • pp.302-305
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    • 2005
  • In this study, settlement characteristics of 38 CFRD was investigated from monitoring data and the method to estimate the dam settlements considering valley shape during constructions was proposed. The construction modulus of dam was found to be dependent on void ratios and valley shape factor. The construction modulus varied with valley shape and decreased with increasing void ratio. Also, the modulus was increased when the shape coefficient was less than 4. The settlement investigation results showed that the total settlement was proportional to the value of the settlement coefficient multiplied by the shape coefficient divided by void ratio.

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이상치를 이용한 관측적 침하예측기법의 개발 (Development of a Observational Settlement Analysis Method Using Outliers)

  • 우철웅;장병욱
    • 한국농공학회지
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    • 제45권5호
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    • pp.140-150
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    • 2003
  • Observational methods such as the Asaoka's method and the hyperbolic method are widely applied on the settlement analysis using observed settlement. The most unreliable aspects in those methods is arose from the subjective discretion of initial non-linearity on linear regression. The initial non-linearity is inevitable due to the settlement behaviour itself. Therefore an objective method is essential to achieve more reliable results on settlement analysis. It was found that the initial non-linear data are statistical outliers. New automation algorithms of the hyperbolic and the Asaoka's method were developed based on outlier detection method. The methods are a successive detection of outliers and a searching method of suitable hyperbolic range for the Asaoka's and the hyperbolic method respectively. Applicability of the algorithms was verified through case studies.

침하량과 과잉간극수압을 이용한 압밀도의 추정 (Estimation of the Degree of Consolidation using Settlement and Excess Pore Water Pressure)

  • 이달원;임성훈
    • 한국농공학회지
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    • 제44권3호
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    • pp.111-121
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    • 2002
  • This study was performed to estimate the degree of consolidation using excess pore water pressure in the very soft ground. The final settlement prediction methods by Hyperbolic, Asaoka and Curve fitting methods from the measured settlement data were used to compare with the degree of consolidation estimated by excess pore water pressure. The dissipated excess pore water pressure during embankment construction and the peak excess pore water pressure on the completed embankment were used for the estimation of the degree of consolidation. After completion of embankment, it was concluded that the degree of consolidation estimated from dissipated excess pore water pressure was more reliable than that from the peak excess pore water pressure. And, the degree of consolidation estimated from the surface settlement was nearly the same as settlement of each layer. The degree of consolidation estimated from dissipated excess pore water pressure was a little larger than that from settlement.

석괴댐의 축조 중 내부 침하 거동 평가 (Evaluation of Internal Settlement of Rockfill Dam under Construction)

  • 서민우;김용성
    • 한국농공학회논문집
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    • 제52권4호
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    • pp.45-52
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    • 2010
  • The purposes of this research are to analyze the internal settlement behavior of Concrete Faced Rockfill Dam (CFRD) typed 'D dam' and to evaluate the stability of the 'D dam' during dam construction using internal settlement measurements and results of numerical analysis. The field measurements were obtained during dam construction period. The numerical analysis was also carried out for the same construction period. The numerical analysis focused mainly on prediction of stress and displacement behavior of 'D dam' during dam construction stage using input parameters obtained from laboratory tests, i.e. large triaxial tests. The behavior of 'D dam' was evaluated to be stable from comparing the results of field measurements and numerical analysis. A simple empirical equation is also presented to predict final settlement at the completion of dam construction, using settlement measurement monitored during dam embankment.

유기질층을 포함한 고소성 실트질 연약지반의 침하 예측 (Prediction of Settlement for the Highly Plastic and Silty Soft Ground Contained of the Organic Deposits)

  • 유남재;김겸;유창선
    • 산업기술연구
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    • 제31권B호
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    • pp.91-98
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    • 2011
  • In this thesis, from the results of settlement measurement performed at the site where embankment earthwork was carried out on the ground consisting of highly plastic and silty soft soils interlayered with organic deposits, various methods of predicting the embankment settlement such as Hoshino's method, Asaoka's method, hyperbolic method, ${\sqrt{s}}$ method and Monden's method were used to investigate their applicability and the inverse method of finding the soil parameter related to consolidation was used to predict the consolidation behavior in the future. It was confirmed that reliable prediction of consolidation behavior under various conditions could be done to estimate soil parameter related to consolidation such as the consolidation index and consolidation coefficient by the inverse method of comparing the measured settlement with the predicted value by the settlement prediction methods.

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유한요소법에 의한 얕은 기초의 지지력 및 침하 특성 연구 (A Study of Bearing Capacity and Settlement of Shallow Foundation by FEM)

  • 박종수;박춘식;장정욱
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2006년도 춘계 학술발표회 논문집
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    • pp.1312-1319
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    • 2006
  • This thesis studied the scale effects on bearing capacity and settlement characteristics by using FEM. The conclusions of the study are as follows. 1) For sandy soil, the bearing capacity ratio increased in the form of logarithm as the foundation width increased. Hence application of static mechanic theory results in overestimation of the bearing capacity when the bearing capacity should be derived from plate loading test results. 2) In clayey soil, the characteristics of the bearing capacity associated with foundation width met Terzaghi's bearing capacity theory. 3) In sandy soil, the settlement ratio increased non-linearly as foundation width increased. However, in clayey soil, the settlement ratio increased linearly. 4) In ordinary soil, the foundation width - settlement ratio turned out to be close to that of sandy soil.

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