• 한국농공학회지
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• 제25권4호
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• pp.69-79
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• 1983

The objective of this study is to analyze the present situation of compaction equipment used in the earth fill dam construction, and the compaction effects of varions types of equipment on core and pervious zones of the fill dam. The results obtained are summarized as follows; 1. Banking materials mostly used for the core zone were soils classified as CL, SC and ML, while those classified as SM, ML and SC were predominant for the pervious zone. 2. Equipments used practically in the real fields were considerably different from those specified in the designs. 3. It was found that the relationship between optimum water content and maximum dry density for both core and pervious materials showed to be linear, ranging from 10% to 25% water content. That is, ${\gamma}$dmax (core) = 2.2555-0.0284 Wopt ${\gamma}$dmax(pervious) =2.239-0.028 Wopt 4. The generalized compaction guides for all kinds of equipment and soil types consi- dered in this study may be recommended as N=8-10 T=2Ocm, N=10-12 T=3Ocm for core zone(98%) and N=6-8 T=2Ocm, N=8-10 T=3Ocm for pervious zone (95%). 5. The coefficient of permeability in the field tests showed abont 10 times as high as the laboratory test value. This large deviation, however, was due to the horizontal permeation and considered not to be significant in the light of the satisfactory compaction ratio in the field compac- tion.

• 터널과지하공간
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• 제22권2호
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• pp.157-161
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• 2012

본 논문에서는 산업용 폭약을 이용한 충격고화기술을 ZnO-98%과 $Ga_2O_3$-2% 혼합분말에 적용하여 직경 30mm, 두께 6mm인 $ZnOGa_2O_3$고화체를 형성 시켰다. 고화체의 경도 및 상대밀도는 각각 220~250 Hv, 97%이었으며, 표면에 대한 주사현미경 관찰결과 균열 및 결함은 발생되지 않았으며, 분말입자들은 강한 충격파에 의해 변형되어 서로 결합되었음을 확인하였다. 또한 X-ray 분석결과로부터 입자 간의 격자결합 및 결정자의 변형을 확인 할 수 있었으며, 이러한 격자결합과 결정자의 변형은 높은 전기저항의 원인이 된다는 것을 보여주었다.

• Journal of the Korean Wood Science and Technology
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• 제34권5호
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• pp.79-87
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• 2006

Value-added utilization of the disposed ash trees due to the infestation by Emerald Ash Borer (EAB) was explored by converting them into particleboards (PBs) and wood-plastic composites (WPCs). The experimental result showed that PB panels could be successfully manufactured from the ash wood but compaction ratio need to be higher than 1.3 in order to meet the standard requirements listed by American National Standards Institute (ANSI). Ash wood plastic composites with high density polyethylene (HDPE) and polypropylene (PP) were also prepared with additives by extrusion. Physical and mechanical properties of ash wood plastic composite compared favorably to those made of pine and maple.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.851-852
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• 2006

The introduction of ceramic particulate into metallic powder will unavoidably lower the compressibility and formability of the mixed powder. In this study, warm compaction, which is a simple and low cost technique to produce high density PM parts, was introduced in preparing composite. The aim of this paper is to prepare the warm compacted NbC particulate reinforced Fe-based composite, then study its tribological behavior and application in the valve-guide cup. A 15 wt.% NbC reinforced iron-based composite was prepared. It possesses a relative density of 98%, a tensile strength of 515 MPa, a hardness of HRC 58 and a remarkable tribological behavior.

• 한국환경복원기술학회지
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• 제8권1호
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• pp.1-9
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• 2005

This study was conducted to establish a management plan for the Sangrim Woodlands restoration by analyzing the site characteristics of the Sangrim Woodlands Natural Monument(Natural Monument 154) in Hamyang-Gun, Gyoungsangnam-Do, Korea. Site preparation to enhance soil aeration should be applied because soil bulk density in all study sites was higher than soil compaction of natural forest soil area. Herbaceous plants could be introduced to hard soil strength for restoration of areas compacted by visitors. Also, visitors around forest areas should be restricted to enhance natural soil restoration. Soil pH in the Sangrim Woodlands was between 4.18 and 4.90. The values were lower than pH 5.34 of Korean forest soil originated from metamorphic parent materials. Lime fertilizer could be applied to reduce soil acidification in the woodlands. Short and long-term management plans such as periodical fertilizations to improve plant growth should be established to restore the Sangrim Woodlands which have high soil compaction, low soil pH and organic matter content.

• 산업기술연구
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• 제18권
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• pp.77-86
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• 1998

This study is to provide the useful data for the design and construction of the geotechnical engineering works by collecting and analyzing the soil properties of granite soil in the Kangwon Province. Data base was obtained from 92 field sites in the Kangwon province divided into 15 areas based on administration district. Total numbers of data were 478. Correlations between soil constants, especially compaction properties, were obtained by performing statistical analysis. Analyzed results were as follows. 1. Most of granite soil consists of SM and GM based on United Soil Classification System. 2. Mean gravity of granite soil is 2.65 3. High correlations between optimum moisture content and the maximum dry density, plasticity index and liquid limit are obtained. 4. Analyzed results between other soil constants show relatively low correlation. However, they show consistent trends matchable to geotechnical engineering senses.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 추계 학술논문 발표대회
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• pp.28-29
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• 2017

For this study, alkali-activated slag red-mud pavement is manufactured to examine the usability of red-mud as a recycling material in the construction industry. In the compaction curve in terms of the replacement ratio of red mud by binder type, the dry density changed gradually depending on the water content, which implies that there is no distinct difference in compaction according to the replacement ratio of red mud. The compressive strength at 28 days was observed to be 18.9~27.0MPa in ASS, and 18.4~28.8MPa in OPC, showing a similar level between the specimens.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.531-532
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• 2006

The effects of compaction pressure and sintering temperature on the densification of Fe-40wt%Ni alloy nanoparticles were analyzed. The Fe-Ni nanoparticles were fabricated by an arc-discharge method and then, compacted at three different pressures and sintered at 550 to $900\;^{\circ}C$. Densification was completed at temperature as low as $600\;^{\circ}C$ and high-pressure compaction was found to enhance densification. Densification behaviors and microstructure developments have been investigated through density measurements, electron microscopies, and hardness measurements.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.385-386
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• 2006

For attaining optimum fatigue resistance of PM steels, high density levels are necessary. In this work, sintered steels Fe-1.5%Mo-0.6%C and Fe-1.5%Cr-0.2%Mo-0.6%C were produced with density levels of 7.1 to $7.6\;g.cm^{-3}$. Ultrasonic fatigue testing with 20 kHz was performed in push-pull mode up to 10E9 cycles. It was shown that the fatigue endurance strength is strongly improved by higher density levels, but also higher sintering temperatures are beneficial. The Cr-Mo steels proved to be superior to the plain Mo alloyed, due to a more favourable as-sintered matrix microstructure.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 추계학술대회 논문집
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• pp.17-18
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• 2007