• Title/Summary/Keyword: Reclaimed ground

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On the Accumulation of Minerals with the Plant Species in a Reclaimed Land (干拓地 植物의 無機營養素 蓄積에 對하여)

  • Min, Byeong Mee
    • The Korean Journal of Ecology
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    • v.13 no.1
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    • pp.9-18
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    • 1990
  • For reaserching the factors of plants micro-distribution, accumulation of 5 minerals-total-nitrogen, phosphorus, potassium, sodium and calcium-for 19 plant species was investigated in reclaimed land, in western coast of Korea, In the five minerals, sodium contents were quite different among the species. Plant species were divided into 4 groups based on the sodium accumulation and accumulation site in plant tissue: Na accumultion type above-ground part>below-ground part : Triglochin maritimum, Chenopodium virgatum, Atriplex subcordata, Salicornia herbacea, Suaeda japonica, suaeda asparagoides, Limonium tetragonum, Aster tripolium, Artemisia scoparia, Sonchus brachyotus above-ground partbelow-ground part : Zoysia sinica, amagrostis epigeiosa bove-ground part

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A Study on the Ground Improvement Effective Evaluation of Reclaimed Land Using Cone Penetration Test (CPT를 이용한 준설매립지반의 개량효과 평가에 관한 연구)

  • Kim, Jong-Kook;Chae, Young-Su;Kim, Myoung-Mo
    • Proceedings of the Korean Geotechical Society Conference
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    • 2004.03b
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    • pp.910-921
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    • 2004
  • In this study, the pilot tests on the reclaimed land were performed in order to find the suitable construction method with dynamic compaction Type I, Type II at different dynamic energy and hydraulic hammer compaction. The estimation of the compaction through the various pilot tests was performed by the CPT-qc, SPT-N and field density tests. As the result of the pilot tests, it shows that the dynamic compaction method is better than the hydraulic hammer compaction method in the effect of the ground improvement, especially dynamic compaction Type I is much superior to others. When it comes to method for measuring the intensity of the ground, the value of the cone penetration test-resistance(qc) is much suitable for the ground. Besides, the standards for the compaction control, which showed that over 10Mpa at 0 through 5meters in the upper layer and 7Mpa at 5 through 8meters in the lower layer in the CPT-qc, could be found without discrimination of the upper road and lower road on the reclaimed land. And it also found that the intensity of the reclaimed land gets back to the original status in about 10 through 15 days.

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Seismic Motion Amplification Characteristics at Artificial Reclaimed Land (인공 매립 지반에서의 지진파 증폭 특성)

  • Kim, Yong-Seong;Moon, Yong
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.03a
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    • pp.1134-1139
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    • 2005
  • Seismic motion amplification owing to the input motion level at bedrock is one of the important topics to understand various geomaterials behavior. The extremely valuable borehole records at Port Island were obtained during the 1995 Hyogoken Nanbu Earthquake and also before and after the main event. In this study, the seismic motion amplification at the soft reclaimed ground was discussed. Comparison of measured records with numerical simulation results were made with focus on seismic motion amplification characteristics at the soft reclaimed ground.

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Tree-Ring Growth Characteristics of Zelkova serrata Makino after Replanting on the Reclaimed Land from the sea in Gwangyang Bay (광양만 임해 매립지 느티나무 이식 이후의 연륜생장 특성)

  • Kim Do-Gyun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.33 no.6 s.113
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    • pp.40-50
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    • 2006
  • This study was carried out to examine the tree-ring growth characteristics of Zelkova serrata Makino after replanting, for the built-up planting founds for stability of landscaped trees in the reclaimed land from the sea. the factors, many affecting the growths of Zelkova serrata Makino, were the replanting stress and drought. The growth reduction due to replanting and drought occurred in the replanting year and the following year. The mean sensitivity(year-to-year variation) and the coefficient of variation(tree-to-tree variation in a certain year) in tree rings of Zelkova serrate Makino, were higher in the poor soil sites than in the favourable soil ones. And the poor soil sites were the filled ground of improve soil and the covered ground of improve soil and the top ground of big mounding than mounding ground sites, especially soil hardness, alkali soil, high $Na^+\;and\;K^+,\;low\;Ca^{++}\;and\;Mg^{++}$ and T-C were the most crucial. We suggest technique development of the built-up planting ground for stability in the reclaimed land from the sea. The built-up planting grounds in reclaimed land from the sea, should be considered for the use of fair soil with the physical and chemical soil properties, -high level foundation of planting ground, and the prevention of disturbed soil-.

Seismic Motion Amplification Characteristics at Reclaimed Ground (매립 지반에서의 지진파 증폭 특성)

  • Kim Yong-seong;Kim Ki-Young;Jeon Je-Sung
    • Journal of The Korean Society of Agricultural Engineers
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    • v.47 no.5
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    • pp.51-61
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    • 2005
  • In this study, borehole records were analyzed to verify the amplification of seismic motion at the soft reclaimed ground before and after the main event of the 1995 Hyogoken Nambu Earthquake at Port Island, Japan. From the analysis, it was shown that the amplification of seismic motion occurred near the soft ground surface (within 30 m below) where confining stress is low. Moreover, it was found that recovery of dynamic soil stiffness at the liquefied ground began gradually 3 hours after the liquefaction and completed in 10 days, when the ground exhibited the same seismic motion characteristics as those before the liquefaction.

Physico-Chemical Properties of Soils at the Ground of Landscape Planting in Reclaimed Land from the Sea (임해매립지의 식재지반별 토양 물리·화학적 특성)

  • Kim, Do-Gyun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.4 no.4
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    • pp.12-18
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    • 2001
  • This study was carried out to analyze physico-chemical properties of soils at the ground of landscape planting in reclaimed land from the sea on Kwangyang Bay, South Korea. Physico-chemical properties of soils at each planting grounds were tested by ANOVA and were significantly(P<0.01) different. The difference came from the soil properties of the covered soil, the disturbance applied to the soil with land use and the accumulation of organic matter after landscape planting. Soil hardness, pH, ECe, Na and K level were in a stable condition at high then low of ground height for landscape planting. Organic matter accumulation was greater at lower planting grounds then top and slope ground of big mounding. The planting grounds of favorable growth for landscape trees were determined as following order : the slope ground and the top ground of big mounding>the ground of medium mounding>the coved ground of improve soil>the lower ground of big mounding>the filled ground of improve soil.

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Correlation Analysis between Physical Properties and Compression Index for Dredged and Reclaimed Marine Clay in the Southern Coast of Korea (남해안 매립 해성점토의 물리적 특성과 압축지수의 상관성 분석)

  • Lim, Seok-Hun;Yoo, Nam-Jae
    • Journal of Industrial Technology
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    • v.34
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    • pp.53-59
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    • 2014
  • The single regression method was used to analyze the correlationship between the compression index with mechanical properties for reclaimed marine clays in the southern coast of Korea. As results of performing regression analysis for 200 samples about reclaimed marine clays in the southern coast of Korea, linear regression lines between compression index and natural water content, void ratio in situ, and liquid limit respectively wer obtained. The changed properties of soil due to disturbance during dredging and reclaiming could be investigated by comparing with the existing empirical correlation equations for the original ground where dredging was performed. These regression equations might be rationally used in the preliminary evaluation of settlement of dredged and reclaimed marine clayey ground in the southern coast of Korea.

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Case Study Top-Base Foundation Static Loading Test in Reclaimed Land (매립지반의 팽이말뚝 평판재하시험 사례 연구)

  • Shin, Eun-Chul;Kim, Sung-Hwan;Lee, Ae-Young
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.10a
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    • pp.721-728
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    • 2008
  • Top-Base Method is a stabilization method for light weight structures particularly in the soft ground. It is widely used for the increment of bearing capacity and the effect of restraining settlement when the bearing capacity of the ground is not enough. Top-shaped cone concrete foundations are installed in graveled laid over soft ground. The principle of the basic method is to maximize effect of dispersing the overburden pressure by increasing the contact area of the top-shaped cone. Therefore, the bearing capacity is increased and the settlement is decreased by the embedded resistance of pile part in the ground. In this paper, the plate bearing test was conducted to evaluate the feasibility of Top-Base foundation. Based on the test results, the coefficient of subgrade reaction, elastic modulus, and settlement of foundation on reclaimed land was derived.

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An Analysis of Farmers' Acceptability for Light-Weight Greenhouse Constructed on Reclaimed Land (간척지 경량형 온실의 농가 수용성 분석)

  • Lee, Hang-Ah;Hong, Na-Kyoung;Oh, Yun-Mi;Kim, Tae-Kyun
    • Journal of The Korean Society of Agricultural Engineers
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    • v.59 no.6
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    • pp.81-87
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    • 2017
  • The total area of domestic reclaimed lands is 54,379 ha, and among these, 30,394 ha can be agriculturally available. To increase an agricultural availability of reclaimed land, controlled horticultural products that can be highly profitable have come to the fore. However, as being characteristically concerning, when original glasshouse is intactly applied in reclaimed land, it is unsafe on account of ground subsidence and, even if ground were reinforced, it has a problem by high cost. So a new greenhouse model would be necessary taking into account not only cost-efficiency but also safety with relatively light-weight one. Before this, this paper estimated acceptance rate of controlled horticultural complexes in reclaimed land and new greenhouse model for 414 farmers. The annual rental fee is 129,712,500 won/ha, considering the interest rate (2.5 %) of the investment, the depreciation cost of the facilities (straight line depreciation method, 20 years of service life estimated), and government subsidy rate (50 %) which resulted in a sufficient number of intended tenants with the acceptance rate of 0.33. The results of this paper may contribute to the government's policies for reclaimed land.

A Study on the Self-Weight Consolidation Procedure of Very Soft Ground Reclaimed by Dredging Clayey Soil (연약한 준설 매립 점성토지반의 자중압밀 과정에 관한 연구)

  • 김형주;오근엽
    • Journal of the Korean Geotechnical Society
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    • v.15 no.2
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    • pp.129-138
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    • 1999
  • This study is performed for the development of a field monitoring and test technique both of self-weight and hydraulic consolidation by which the soil parameters of dredge-reclaimed clay can be obtained effectively. The field monitoring development and tests mentioned above make it possible to reproduce the process of the self-weight consolidation from settling to reclaimed soft ground. The experimental research is mainly focussed on the characteristics of self-weight consolidation of dredged clayey soil. And theoretical study has pointed out the limits in the application of Terzaghi's one dimensional consolidation theory in interpreting reclaimed clayey ground. Furthermore, a finite difference analysis has been made on the basis of Mikasa s self-weight consolidation theory which takes the problems of Terzaghi's theory into consideration. The relationships between specific volume, effective stress, and the coefficient of permeability of Kunsan reclaimed clayey soil have been obtained by laboratory tests. On the other hand, through the field monitoring, pore pressure, total pressure, and water levels have been measured after pouring. The results of these experiments have been analyzed, and compared with those from Terzaghi's method and the finite difference analysis of Mikasa's self-weight consolidation theory. In conclusion, the measured settlements is comparatively consistent with Mikasa's self-weight consolidation theory rather than Terzaghi's consolidation theory.

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