• 한국지반신소재학회논문집
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• 제22권3호
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• pp.61-69
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• 2023

세계 무역 및 항만 산업 환경이 변화함에 따라 선박의 대형화 및 고속화에 대한 대응 필요성이 높아지고 있다. 이에 따라 부산, 울산 등 광역도시를 중심으로 신항만의 건설이 이루어지고 있다. 일반적으로 신항만 건설은 모래 또는 자갈을 사용한 다짐공법이 적용되고 있다. 하지만 모래 또는 자갈이 부족하고, 단가상승으로 인해 경제성 확보가 어려워 최근에는 단시간에 요구되는 압축강도를 확보할 수 있는 심층혼합공법이 사용되고 있다. 따라서 본 연구에서는 순환자원을 이용한 CMD-SOIL을 울산지역에 적용하고, 실내 배합시험 및 현장 확인 보링 결과를 분석하여 적용성을 판단하고자 하였다. 시험결과, CMD-SOIL은 설계 배합강도 이상을 나타내었고, 고로슬래그 시멘트와 유사한 성능을 확보할 수 있는 것으로 분석되었다. 또한 현장에서의 확인 보링 결과, 설계 기준강도 이상을 충분히 확보할 수 있어 울산지역에서의 현장 적용성을 고려할 때 CMD-SOIL의 활용이 가능할 것으로 판단된다.

• Geomechanics and Engineering
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• 제19권6호
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• pp.543-554
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• 2019

İzmir Bay reserves high amount of residual alluvial deposits generated by Meles River at its stream mouth. These carried sediments with high water content and low bearing capacity are unsuitable in terms of engineering purposes. In-situ soil stabilization with deep soil mixing method is considered to improve properties of soil in this location. This method is widely used especially over Scandinavia, Japan and North America. Basically, the method covers mixing appropriate binder into the soil to improve soil profile according to the engineering needs. For this purpose, soil samples were initially provided from the site, classification tests were performed and optimum ratios of lime and cement binders were determined. Following, specimens representing the in-situ soil conditions were prepared and cured to be able to determine their engineering properties. Unconfined compression tests and vane shear tests were applied to evaluate the stabilization performance of binders on samples with different curing periods. Scanning electron microscope was used to observe time-dependent bonding progress of binders in order to validate the results. Utilization of 4% lime and 4% cement mixture for the long-term performance and 8% lime and 8% cement mixture for short term performance were suggested for the stabilization of Meles Delta soils. Development of CSH and CAH in a gel form as well as CSH crystals were clearly observed on SEM images of treated specimens.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.473-485
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• 2010

Lightweight materials using in-situ clay soil contain large amounts of fine grain and cement for increasing the strength, lighter weight to increase liquidity for the foam and the bulk of the material is conducted by the water. Domestic cases, Light weight soil to improve cementation and lightness using demountable mixing device is defined Smartsoil. Typical features are their self-leveling, self-compaction, folwability. By adjusting the amount of cement, the strength can be controlled artificially. And re-excavation is easy. In this paper, pre-loading method using the road due to the displacement of adjacent structures under construction as an alternative SmartSoil introduces the design and construction practices. Is to discuss and improve.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 International Symposium
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• pp.89-110
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• 2003

최근 현장(In situ)에서의 토양 및 지하수 오염 정화는 오염물질을 현장에서 추출해 지상에서 처리하는 것이 아니라, 직접 현장에서 미생물 혹은 화학물질과 오염물질의 혼합을 통한 분해기 작을 이용해, 오염물질을 제거하는 과정을 의미한다. 이러한 현장오염정화 기법 중 하나가 Figure 1에 도시한 수직흐름처리정(Horizontal Flow Treatment Wells, HFTWs)으로 2개의 정(well) 중간지점에 반응물질을 설치한 후 각각의 정에서 상향 및 하향흐름을 발생시켜 주위의 지하수를 순환시키면서 정화하는 기법이다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 가을 학술발표회 논문집
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• pp.553-560
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• 2002

The improvement effect of soft ground is estimated by unconfined strength mainly. The unconfined strength of solidification agent treated soil is likely to vary with ununiformed mixing ratio and water content change of in-situ ground place by place. So, it is unreasonable to apply a solidification agent mixing ratio obtained from laboratory test results on all over the soft ground. In this study, it was analysed how the unconfined strength would be effected by the water content of soft ground. For this study, a series of unconfined compressive tests are peformed on various water content soil samples. The test results showed that the strength was fallen to 30∼80% by two times increase of water content approximately, This means that strength of solidification agent treated soil is influenced greatly by water content of raw soft ground and mixing ratio of solidification agent. It was suggested that the method how to decide the mixing ratio with soft ground water content.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 2000년도 Proceedings of 2000 KSAM International Symposium and Spring Meeting
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• pp.100-107
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• 2000

In a recently developed strategy for in-situ treatment of polychlorinated biphenyls (PCB), bioaugmentation was used in conjunction with a surfactant, sorbitan trioleate, as a carbon source for the degrader bacteria, along with the monoterpene, carvone, and salicylic acid as inducing substrates. Two bacteria were used for soil inoculants, including Arthrobacter sp. st. B1B and Ralstonia eutrophus H850. This methodology achieved 60% degradation of PCBs in Aroclor 1242 after 18 weeks in soils receiving 34 repeated applications of the degrader bacteria. However, an obvious limitation was the requirement for soil mixing after every soil inoculation. In the research reported here, bioaugmentation and biostimulation treatment strategies were modified by using the earthworm, Pheretima hawayana, as a vector for dispersal and mixing of surface-applied PCB-degrading bacteria and soil chemical amendments. Changes in microbial biomass and microbial community structure due to earthworm effects were examined using DNA extraction and PCR-DGGE of 16S rDNA. Results showed that earthworms effectively promoted biodegradation of PCBs in bioaugmented soils to the same extent previously achieved using physical soil mixing, and had a lesser, but significant effect in promoting PCB biodegradation in biostimulated soils treated with carvone and salicylic acid. The effects of earthworms were speculated to involve many interacting factors including increased bacterial transport to lower soil depths, improved soil aeration, and enhanced microbial activity and diversity.

• 기술사
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• 제44권6호
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• pp.45-50
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• 2011

As the Deep Cement Mixing Method is composed of drilled natural soft soil structure and injected cement slurry to be mix together in it, the nature of excavated ground is influenced directly to the application of constructability. Also the nature of in situ soil is the main material, the mix design and construction work plan should be established before the investigation of soil which is performed through the whole site confirm the soil parameter before construction. The nature of investigated soil and water level as should be performed accurately.

• 한국지하수토양환경학회지:지하수토양환경
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• 제28권1호
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• pp.15-24
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• 2023

A persulfate(PS)/sulfidated microscale zero-valent iron(S-mZVI) system was tested for treating a soil contaminated with phenol. Sulfidation of bare mZVI was conducted using a mechanochemical process utilizing a ball mill in order to improve persulfate activation capacity and stability of unmodified mZVI. The synthesized S-mZVI performed markedly better than the bare mZVI in activating PS. The optimum molar ratio of sulfur to mZVI was around 0.12. In the soil slurry experiments, a very rapid and complete removal of phenol was observed at the optimum molar ratios of PS to S-mZVI of 2:1 and PS to phenol of 16:1. The phenol removal efficiencies decreased as the water content of the slurries decreased. This was believed to be due to increased soil oxidant demand as the amount of soil was increased as relative to the water content. To evaluate the field applicability of the process, slurry experiments adopting high soil contents were carried out that simulated in-situ soil mixing conditions. These experiments resulted in substantially compromised degradation efficiencies of 54.3% and 43.8% within 4 hours. The current study generally shows that the PS/S-mZVI process has a potential to be developed into a remediation technology for soils contaminated with organics.

• 터널과지하공간
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• 제25권6호
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• pp.505-514
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• 2015

본 연구에서는 기존 오염토양 안정화처리 시공방법의 문제점에 대한 해결을 위하여 개발한 혼합포설방식 안정화장비의 현장 적용성 및 시공성을 현장실증시험 및 실내시험을 통하여 검증하였다. 현장 실증시험을 통하여 안정화장비의 현장 적용성을 확인하였으며, 현장 교반토의 석회석 분포 및 CaO 함량 분석 등의 실내시험을 통하여 기존 오염토양 안정화처리 시공방법에 비해 개발된 안정화장비 시공방법의 안정화제 교반성이 더 우수한 것을 확인하였다.

• 대한토목학회논문집
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• 제29권5C호
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• pp.229-237
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• 2009

전통적인 되메우기 방법은 모래 또는 현장발생토를 다짐하는 공법이 주로 사용되어 왔으나 이는 시간과 비용이 많이 든다. 특히 관의 하부 및 작은 틈새와 같은 부분은 전통적인 다짐 공법으로는 다지기가 난해하기 때문에, 이러한 문제점을 보완하기 위해 현장토를 재활용함으로써 모래 수급 문제를 해결하고 배합설계를 통해 유동성 및 강도를 임의로 조절할 수 있는 유동화 처리토 공법이 제안되었다. 본 연구에서는 현장토의 유기물 함유량에 따른 유동화 처리토의 배합 특성을 파악하고자, 휴믹산 함유량에 따른 재료분리특성, 유동성, 강도특성, 투수특성을 실내실험을 통해 측정하여, 비교 분석하였다. 그 결과, 휴믹산 함유량이 증가할수록 재료분리 특성과 유동성은 크게 나타났고, 강도는 유기물 함유량과 반비례하는 것으로 나타났다. 또한 유기물 함유량은 유동화 처리토의 투수특성에는 영향을 미치지 않는다는 것을 알 수 있었다.