• 한국안전학회지
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• 제12권3호
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• pp.147-154
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• 1997

The main purpose of this study is to investigate the failure surface in a soil mass by a excavation of the model ground. The failure mechanism of an earth structure is usually determined from field failure observations or from laboratory model tests at failure. To study the failure surface for the excavated slope, laboratory model tests were performed by changing the angle of the excavated slope and the ground condition. Results of the laboratory model tests were compared with those obtained with theoretical solutions using limit equilibrium analysis method. The results of model tests show that, there is a failure to create a straight line in the low angle of excavated surface and a create a circle as the angle increases. As the angle of excavated surface is increasing, the angle of the failure surface increases too. In the angle of the failure surface, the submerged ground is less than the dry ground at $3.2^{\circ}$.

• 상하수도학회지
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• 제32권3호
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• pp.269-277
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• 2018

Burials for the rapid disposal of carcasses have diverse and profound effects on the rural living condition, natural environment, and local economy throughout construction, management and final destruction of burials. In this study, possible residue excavated from standard burials, storage using FRP (Fiberglass Reinforced Plastic) tanks, and microbial-treated burials are characterized as carcasses, contaminated soil by leachate, and wasted plastic film. Treatment technologies for volume reduction of the residue including composting, rendering, and thermal hydrolysis were investigated. If the solid and liquid residues generated during volume reduction treatment are directly transferred to the environmental facilities, it may cause disorder due to high concentrations of organics, antibiotics, and lipid. Benefits and drawbacks of composting as a volume reduction techniques are extensively investigated. We also discussed that proper treatment of excavated soils and the reusing the treated soil as agricultural purpose. For the protection of public health and worker's hygiene, treatment criteria including produced residue qualities, and quality standards for the treated soil as agricultural use are required. In addition, Scientific manual for the proper treatment of residues is required. It is necessary to consider the establishment of a pretreatment facility to the occurrence of large-scale residue treatment.

• 보존과학회지
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• 제34권6호
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• pp.549-556
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• 2018

In November 2011, various artifacts were excavated from the No. 8 stone-lined tomb in Suchon-ri, Gongju by the Chungnam Institute of History and Culture. These included artifacts with lacquered mainframe and silvery metal ornament. These were recovered together with soil and underwent conservation treatment. In this paper, we discuss the scientific analysis and conservation treatment of the lacquered artifacts excavated from the Suchon-ri site. Among our findings is that the artifacts have three layers of lacquer coating and the metal parts are primarily composed of Ag. As the artifacts were recovered with soil from the site, the soil was removed from underneath and inside the artifacts. The inside of the lacquerware was reinforced with rayon paper using 3% funori, and the metal was treated with acrylic resin after removing the acrylic resin previously used to recover the artifact, followed by cleaning. The metal was also internally reinforced with gauze. Finally, the interior reinforcement was made using PVA and resin in pulp and attached with funori to preserve the shape of the lacquerware, and the exposed rayon was finished with acrylic paint. The main advantages of this study are its review of conservation treatment strategies for lacquer artifacts whose numbers have recently increased, and the application of new conservation treatment methods.

• 한국건설순환자원학회논문집
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• 제8권4호
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• pp.450-457
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• 2020

본 연구에서는 현장 굴착토를 활용한 속경성 유동성 채움재의 배합요인별 유동성, 재료분리 저항성, 재령별 압축강도 등의 공학적 특성을 검토하여 속경성을 발현하는 배합비 및 결합재 조건을 도출하였으며, 이를 토대로 현장 모사 실험을 실시하여 현장에서 적용 가능한 후속공정 개시기 검토 방법의 유효성을 검토하고자 하였다. Kelly ball 낙하시험과 산중식 토양 경도계의 평가결과 유동성 채움재의 후속공정 개시기 확보 가능한 시간은 동일하게 약 3시간으로 나타났으며, 일축압축강도 시험의 결과와 비교하였을 때 Kelly ball 낙하 시험 및 산중식 토양경도계의 현장 적용성에 대한 유효성을 확인할 수 있었다.

• 산업기술연구
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• 제25권B호
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• pp.55-62
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• 2005

This paper is the results of experimental and numerical works on analyzing the geotechnical engineering behavior and characteristics of excavated clay slope formed by the method of excavated replacement which is one of treatments in soft soil ground. For the centrifuge model tests, models of excavated clay slope were prepared by remolding the marine clayey soil sampled from the field. Tests were performed with changing the slope to investigate the behavior of them. On the other hand, numerical analyses were carried out to analyze the change of safety factor against instability of slope with time. Changes of pore water pressure, shear strength and displacement were also investigated. As results of centrifuge model tests with slopes of 1:1.5 and 1:3 using the confining body of simulating the effect of excavation, for the case of 1:1.5, slope failure occurred right after remove the confining body whereas relatively small displacements within the range of 3.2mm, implying to maintain the stability of slope, were observed for the case of 1:3 slope. From the results of numerical analyses using the software of PLAXIS to investigate the stability of slope after excavation, the minimum safety factor against slope failure was 1.28 for the case of 1:3 slope. The further researches in the future are required with considerations of build up of static pore water pressures during acceleration of centrifuge, depth of excavation influencing the behavior of the slope and permeability of the slope since excavation of the slope was not simulated well resulted from the limitations of apparatus at the stage of excavation during the centrifuge tests.

• 한국안전학회지
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• 제13권3호
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• pp.135-142
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• 1998

This paper is to investigate the failure surface and modes in a soil mass by a excavation of the model ground. To study the failure surface for the excavated slope, centrifugal model tests were performed by changing the angle of the excavated slope(50, 75, $90^{\circ}$) and the ground condition($D_r$=60, 90%, dry and submerged ground). Excavation was simulated during the centrifuge tests by operating a valve that allowed the zinc chloride solvent to drain from the excavation. Results of model tests were compared with those obtained with theoretical solutions using limit equilibrium analysis method. The results of model tests show that, there is a failure to create a straight line in the low angle of excavated surface and a create a circle as the angle increases. Also, as the angle of excavated surface is increasing, the angle of the failure surface increases. The failure length in the submerged ground increases approximately 1.10~1.34 times more than that of the dry ground.

• 한국지반공학회논문집
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• 제15권4호
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• pp.261-277
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• 1999

고랑형태로 좁게 굴착된 되메움 공간에 대한 수평 및 연직 토압은 굴착면과 되메움 흙과의 벽면마찰 및 고랑식 되메움공간의 형상에 따라 그 영향을 받는다. 본 연구에서는 대칭수직 굴착면에 대한 Handy의 제안식 및 대칭경사굴착면에 대한 Kellogg의 식을 수정하여 비대칭 굴착형상의 되메움 공간에 대한 수정식과 최소주응력아치 형태를 나타내어 보였다. 수정된 식은 모형토조 실험결과와 비교하였을 때 되메움 토압의 크기, 분포 등 그 경향이 매우 유사하였으며 비대칭으로 경사진 공간에서의 되메움 토압이 대칭적으로 수직하게 굴착된 공간에서의 토압보다 2배 이상의 큰 크기와 현저한 아칭현상의 저하를 보였다. 본 연구와 유사한 현장의 구조물에 미치는 토압을 산정할 때 되메움 공간의 형상 및 크기 등을 고려한 토압산정식이 적용되어져야 할 것으로 확인되었다.

• 유기물자원화
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• 제27권2호
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• pp.5-12
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• 2019

과거 산업화와 경제발달 과정에서 증가하였던 폐기물이 일부 단순 투기되거나 비위생 매립시설에 최종 처분된 사례가 있다. 매립지 사용종료 및 신규 매립지 확보를 위해 사용이 종료된 비위생매립지 정비 사업들의 시행과 폐기물의 자원화 정책이 강화되면서 매립억제 및 기매립 자원의 재활용을 위한 매립폐기물의 순환이용과 순환형매립지 조성사업이 확대되고 있다. 폐기물혼입굴착물은 순환형매립지의 조성, 매립지 정비사업 및 각종 건설공사 등 다양한 굴착 현장에서 발생되며 자원의 유효이용과 폐기물의 적정처리를 통한 관리가 필요하다. 본 연구에서는 택지개발, 순환형매립지 정비, 비위생매립지 정비 등 굴착 선별 공사가 진행 중인 사업장 3개소를 대상으로 폐기물혼입굴착물의 선별을 통한 선별가연물, 선별토사의 물리화학적 조성 및 특성분석을 통해 선별회수자원 및 잔재물의 특성을 검토하였다. 그 결과, 굴착 선별된 가연물의 부착토사 및 불연성분으로 인해 소각처리 시 운영효율 저하 혹은 고형연료 제조 시 제품의 품질기준을 충족하지 못할 수 있으므로 선별가연물의 불연물 함량을 관리할 필요가 있다. 선별토사의 경우, 매립된 폐기물의 유기성분이 토사 중에 잔존할 수 있으므로 굴착 선별된 토사류의 적정 재활용을 위해서는 선별토사의 유기물질을 관리하여야 할 것으로 판단되었다.

• 보존과학연구
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• 통권26호
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• pp.127-139
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• 2005

We have conserved the sword with round pommel with a tri-ring which was excavated from No. 1 tomb of the Duckcheon-ri at the Gyeongju and requested from Jungang Research Center of the Cultural Heritage. When this artifact excavated, it was pressed flat state because of the influence of earth pressure and stuck to a gravel and soil laid scattered on the wooden coffin. If the artifacts is handled without plan, it can be damaged, therefore that sword was collected together with soil using the Polyurethane foam. After the artifact which had a weak specific and was collected using a this method can be safetly collected as below; First, we made the supporter of article ordered using a silicon and gypsum. The silicon can conserve the weak point of the artifact because it has a flexible and smooth properties and the gypsum can adhere closely to the artifact because it has a little expansion and shrinking but a hard and fluid characters. Consequently, gypsum is a good complement to the weak point of the silicon. Second, During a remove gauze and a reinforcing agent from the surface of a artifact which was reinforced using a acetone steam method. The acetone steam method can be supplement to a dangerous problem of acetonedircet method because this can be damaged in a surface of the artifact.

• 보존과학연구
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• 통권27호
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• pp.203-214
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• 2006

The work focuses on the chemical analysis of organic residues in archaeological soils. Particularly, the detection of manuring in archaeological soils can provide important information concerning early human behavior, diet, parasites, ecological adeptation. In this study, archaeological soils excavated at bunto-ri, Haenam and kumjang-ri, Kyungju were used to assess the possibility as indicators of ancient human activity in archaeological areas. The sampled soils were analyzed soil color, pH for their physical and chemical properties and GC/MSD to detect and quantify specific compound. The results showed that the sampled soils were normal pH(6.8~7.2) and soil color of light brown to yellowish brown. Also, the result from the GC/MS analysis indicated that their compounds were hexadecanoic acid, octadecanoic acid, nonadecane, docosanoic acid, methyl ester, teracosanoic acidand methyl este from bunto-ri site and 1-heptadecene, cyclotetracosane, tetracosane, cyclotetracosane,1-docosene, n-nonadecane, tetracosanoic acid methyl ester, cyclooctacosane, 1-nonadecene, eicosane, cyclotriacontane from kumjang-ri site. These compounds are not only normal soil materials but also animal lipid compounds. And the more scientific analysis of the soils will solve a curiosity for artificially incoming.