• 산업기술연구
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• 제35권
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• pp.81-88
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• 2015

The single regression method was used to analyze the correlationship between the compression index with mechanical properties for reclaimed marine clays in the Gyeonggi coast of Korea. As results of performing regression analysis for 62 samples about reclaimed marine clays in the Gyeonggi coast of Korea, linear regression lines between compression index and natural water content, void ratio in situ, and liquid limit respectively were obtained. The changed properties of reclaimed 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.

• 산업기술연구
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• 제23권A호
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• pp.131-137
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• 2003

This thesis is results of centrifuge model experiments to investigate the behavior of replacement method in dredged and reclaimed ground. For experimental works, centrifuge model tests were carried out to investigate the behavior of replacement method in soft clay ground. Basic soil property tests were performed to find mechanical properties of clay soil sampled from the southern coast of Korea which was used for ground material in the centrifuge model tests. Reconstituted clay ground of model was prepared by applying preconsolidation pressure in 1g condition with specially built model container. Centrifuge model tests were carried out under the artificially accelerated gravitational level of 50g. Replacing material of leads having a certain degree of angularity was used and placed until the settlement of embankment of replacing material was reached to the equilibrium state. Vertical displacement of replacing material was monitored during tests. Depth and shape of replacement, especially the slope of penetrated replacing material and water contents of clay ground were measured after finishing tests. Model tests of investigating the stability of embankment after backfilling were also performed to simulate the behavior of the dike treated with replacement and backfilled with sandy material. As a result of centrifuge model test, the behavior of replacement, the mechanism of the replacing material being penetrated into clay ground and depth of replacement were evaluated.

• 한국지반공학회논문집
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• 제23권8호
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• pp.47-57
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• 2007

본 연구는 사질토로 준설매립된 지반의 액상화 평가를 위해 반드시 요구되는 초기 밀도특성을 분석하였고, 국내 내진 설계기준에서 제시한 SPT-N을 이용한 액상화 간편예측 방법의 문제점을 분석하여 개선방안을 제시하였다. 기존 시공사례를 토대로 매립 직후 준설매립지반의 밀도특성을 분석한 결과, 상대밀도와 초기 N값은 대체로 각각 $40{\sim}50%,\;5{\sim}8$의 범위에 분포하였다. 액상화 간편예측에 있어서 유효상재압 보정의 Liao & whitman식은 항상 지진에 취약한 상부층이 하부층보다 액상화 저항응력이 크게 산정되어 Skempton식의 적용이 추천된다. 또한, 설계단계에서 준설매립 지반의 심도별 N값을 산정할 경우에는, 유효응력에 따른 N값의 변화를 나타내는 누승함수 $N=1.35{\sigma}^{'0.75}$를 이용하여 액상화 간편예측을 실시할 것을 추천한다.

• 한국지반공학회논문집
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• 제22권5호
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• pp.13-26
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• 2006

본 연구에서는 인천지역 준설매립지반을 대상으로 액상화 평가방법들에 대해 검토하고, 국내 지진특성을 고려하여 지진규모 6.5을 기준으로 액상화 가능성을 비교하였다. 그리고 다짐시험시공 및 동다짐 전 후에 수행한 표준관입시험 (SPT) 및 정적콘관입시험(CPT)을 토대로 지반개량효과 및 액상화 보강효과를 평가하였다. 그 결과, 동다짐은 다짐에너지가 클수록 개량효과가 우수한 것으로 나타났으며, 동다짐 후 지반강도 증가에 따라 액상화 안전율도 크게 증가되어 내진성능 향상을 크게 도모 할 수 있는 것으로 평가되었으며, 이에 따른 매립지반의 다짐관리 방안을 제시하였다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.1170-1180
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• 2009

Recently this country has carried out the coast reclamation centering on the west and south coast for effective practical use of a country, considering purchase of materials and environmental problem, most reclaiming work is processing to spoil reclamation which is easy to secure the amount of materials. In case of weak ground that is formed by spoil reclamation like this, initial moisture content is high, as slurry state that is rarely revealed ground strength, compressibility and water permeability have been shown nonlinear change by compaction progress. Analysis of weak ground is unreasonable because the existing Terzaghi compaction theory analyzes compaction fixed number to regular invariable number for prediction of compaction state. This study computes the relation with void ratio-effective pressure and void ratio-finite transformation which is the most basic matter to predict finite strain compaction state of the south coast spoil, and analyze the basic feature to predict compaction feature of the south coast spoil reclaimed ground.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2003년도 학술발표논문집
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• pp.143-146
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• 2003

• 한국콘텐츠학회논문지
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• 제12권8호
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• pp.380-387
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• 2012

매립 문화재 위치 추정에 있어서 비파괴검사인 복합지구물리탐사 방법이 최근에 많이 활용되고 있다. 이러한 탐사방법은 건설 현장에서 효율적으로 빠른 시간 내에 매립 문화재 위치를 추정하는데 있어서 가장 합리적인 방법이라 할 수 있다. 본 연구는 과거 매립 문화재가 조성되었을 가능성이 있는 지역을 대상으로 그 분포 영역을 파악하기 위해 자력변화율탐사, 전기비저항탐사, 지하투과레이더탐사 방법을 병행하여 매립 문화재 위치를 추정하였다. 본 연구대상지역에서의 연구성과로는 도면좌표로 X축 방향으로 약 +15m, Y축 방향으로 약 +90m에 위치하고 있으며, 장축으로 북북동방향으로 약 20m, 폭이 약 5m의 형태로 나타났고, 예상 이상대 발달분포의 심도는 약 1.5~3.0m인 것으로 추정되었다. 이와 같은 해석 결과로 향후 매립 문화재 예상 지역 및 발굴작업에 있어서 지구물리탐사 방법을 이용한다면 보다 효율적으로 정확한 측정방법을 제시할 수 있을 것으로 기대된다.

• Journal of Ecology and Environment
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• 제32권4호
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• pp.267-275
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• 2009

To investigate the possible applications of plants to remediate heavy-metal-contaminated soil, a pilot experiment was performed for four years in a reclaimed dredging area using two Alnus species, i.e., Alnus firma and Alnus hirsuta. In a comparison of phytomass of the two species at two different planting densities, the phytomass of Alnus planted at low density was twice as high as that of Alnus planted at high density after four years. The Alnus species showed active acclimation to the heavy-metal-contaminated soil in a reclaimed dredging area. A. hirsuta showed greater accumulation of phytomass than A. firma, indicating that it is the better candidate for the phytoremediation of heavy-metal-contaminated soils. In the pilot system, Alnus plants took metals up from the soil in the following order; Pb > Zn > Cu > Cr > As > Cd. Uptake rates of heavy metals per individual phytomass was higher for Alnus spp. planted at low density than those planted at high density in the pilot system. Low plant density resulted in higher heavy metal uptake per plant, but the total heavy metal concentration was not different for plants planted at low and high density, suggesting that the plant density effect might not be important with regard to total uptake by plants. The quantity of leached heavy metals below ground was far in excess of that taken up by plants, indicating that an alternative measurement is required for the removal of heavy metals that have leached into ground water and deeper soil. We conclude that Alnus species are potential candidates for phytoremediation of heavy-metal- contaminated surface soil in a reclaimed dredging area.

• 한국조경학회지
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• 제28권4호
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• pp.9-20
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• 2000

The purpose of thus paper is to provide the knowledge on preparing for the planting soil and planting method, and maintenance at the reclaimed seaside. Based on the collected data from the field work, the soil environment, the growth of height, inter-node, tree ring and roots of the two species had been analyzed. The determinant of soil factors, affecting the growth of trees, turned out to be six elements such as soil hardness, soil acidity, potassium, calcium, magnesium and total nitrogen. Because the variances of both growth of tree height and tree ring are greater than that of root, the growth characteristics of ground parts of the species by the individual tree species is more dynamical than those of underground parts. From the mean difference test the growth of height, root between Pinus thunbergii and Zelkova serrata, have been turned out to be statistically significant at 5 percent level. Pinus thunbergii is a sapling, so it grows faster than Zelkova serrata while Pinus thunbergii has better roots system than Zelkova serrata. From the correlation analysis, it showed the very strong correlation between tree height growth and potassim, while the lowest correlation coefficient was between soil hardness and potassim as 0.744. From the multiple regression analysis, both soil hardness and magnesium affect to the tree growth, soil hardness and potassium to the tree growth, potassium and calcium to the rot growth, respectively. Using this research results, we can be use the planting plan including revegetation, construction and maintenance of the reclaimed seaside. In the future, the planting method including the ground preparation and tree species selection for the reclaimed seaside should be accompanied in advanced through the soil survey and relevant analysis.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2004년도 춘계학술발표회
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• pp.219-226
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• 2004

We measure subsidences occurred in a reclaimed coastal land, Noksan industrial complex, by using JERS-1 SAR (1996-1998) and RADARSAT-1 SAR (2002-2003) dataset. SAR with a high spatial resolution (about several or several tens meter) can reveal the two-dimensional distribution of settlement that would be bardly estimated from in situ measurements. The DInSAR results show significant deformation signal associated with soil consolidation. Accuracy of the settlements estimated by 2-pass differential interferometry (DInSAR) is evaluated using the measurements of settlement gauge. A two-dimensional subsidence map is constructed from 7 qualified pairs. Comparing the JERS-1 radar measurements with the ground truth data yields the correlation coefficient of 0.87 (RMSE of 1.44 cm). The regression line shows the gradient of 1.04 and intercepts close to the origin, which implies that the unbiased settlement can be measured by DInSAR technique. The residual settlements are also detected from RADARSAT-1 pairs. The extent and amount of the settlements are matched well with ground truth data.