• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2004년도 춘계학술발표회
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• pp.90-99
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• 2004

Stone column is one of the soft ground improvement method, which enhances ground conditions through ground water draining, settlement reducing and bearing capacity increasing complexly by using crushed stone instead of sand in general vertical drain methods. In recent, general construction material, sand is in short of supply, because of the unbalance of demand and supply. Also, the bearing capacity improving effect of stone column method is needed in many cases so the bearing capacity estimation is considered as important point. Nevertheless, adequate estimation methods to predict bearing capacity of stone column considering stone column and improving ground behavior reciprocally is not yet prepared. To contribute this situation, bearing capacity behavior of stone column were simulated as numerically on various property cases of crushed stone and surrounded ground. Through the numerical analysis of simulation results, bearing capacity behavior prediction formula was suggested. This formula was verified by comparing the prediction result with in situ test.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1993년도 가을 학술발표회 논문집
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• pp.103-107
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• 1993

The Alkali Aggregate Reaction(AAR), reported first by T. E. Stanton in 1940, is a reaction between certain siliceous aggregate and hydroxyl ions present in the pore fluid of a concrete. The damage of concrete structures, deteriorated by AAR, have been reported since using the crushed stones caused by the exhaustion of natural aggregates. This study was performed to investigate the AAR of crushed stones using chemical analysis, polarization microscope, XRD, chemical method(KS F 2545, ASTM C 289), mortar bar method(KS F 2546, ASTM C 227) and Scanning Electron Microscope(SEM) and Energy Dispersive X-ray Analysis (EDXA) of reaction products by AAR in mortar bar.

• 환경위생공학
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• 제15권4호
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• pp.84-90
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• 2000

5L laboratory-scale anaerobic digester was used to study the effects of food size and washing rate of food waste on the mixed digestion with sewage sludge. Food waste was crushed with particle diameters of 4mm and 2mm and washed two to three times, and seven to eight times before feeding the batch digester. The digester with crushed of washed food waste showed better performance than that with uncrushed of unwashed to produce methane gas of reduce volatile solids. The digester with 2mm food waste showed 17.4% higher VS/TS reduction rate and 18ml higher methane production rate per gram VS input than that with uncrushed food waste, where VS and TS are volatile solid and total solids in the liquid effluent, respectively. Also food waste crushed eight times gave 8% higher VS/TS reduction rate and 11ml higher methane production rate per gram VS input than unwashed food waste.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.13-18
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• 2003

The concrete structure can be easily damaged due to alkali-aggregate reaction. The alkali-aggregate reaction is a reaction between the alkalies(K or Na) in cement and an unstable mineral of the aggregates. There are several test methods to identify alkali reactivity of aggregates. In general, crushed stones are tested by petrographic examination, chemical method and 모르타르 바 method. This study tested alkali-aggregate reactivity of crushed stones that has different rock types such as granitic, volcanic, metamorphic and sedimentary rocks. Samples are collected from 12 local aggregate production companies. Alkali-reactivity of various rock types was evaluated by using ASTM C 227 and C 1260, and compared the test results of two test methods.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2001년도 봄 학술발표회 논문집
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• pp.299-306
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• 2001

Crushed Stone Pile(CSP) is one of the ground improvement methods available to loose sand and clayey ground by forming compacted CSP in the weak soil layer. The effects of this method are enhancement of ground bearing capacity, reduction of settlement and prevention of lateral ground movement in cohesive layer, reduction of liquefaction potential in sandy ground. This study performs model tests in 1.0m${\times}$1.0m${\times}$1.0m and 1.5m${\times}$1.5m${\times}$l.2m model tank to observe bearing capacity of CSP treated ground. The area replacement ratio of CSP composite ground varies 20%, 30% and 40% with square grid pattern. After the composite ground was consolidated under pressure of 0.5kg/$\textrm{cm}^2$ and 1.0kg/$\textrm{cm}^2$, load tests were carried out. The results show that ultimate bearing capacity increases with area replacement ratio and the preconsolidation pressure of ground.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2004년도 학술대회지
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• pp.55-58
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• 2004

This paper investigated the results of quality of concrete using mixed sand with grading adjustment in order to find out the applicability of fine aggregate with bad grading, According to test results, fluidity of concrete with fine level grading river sand was decreased while with coarse level grading crushed sand increased compared with that with medium level grading crushed sand. Use of mixed sand with grading adjustment(MSG) resulted in an improvement in fluidity. Increase in fineness modulus led to an increase in bleeding, For compressive strength, use of MSG increased compressive strength. For drying shrinkage, use of fine level grading river sand resulted in an increasing drying shrinkage due to the larger presence of fine particles, while use of MSG led to a reduction in drying shrinkage

• 한국수산과학회지
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• 제45권6호
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• pp.640-647
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• 2012

Squid Sikhae is a traditional salt-fermented food in Korea. We evaluated the standardization of optimal processing conditions for desirable quality-controlled squid Sikhae using analyses of physiochemical properties, microbiological species, and organoleptic tests. The optimal fermentation temperature, sun-dried sea salt concentration, and fermentation period for manufacturing squid Sikhae products of the aceeptable quality were $10^{\circ}C$, 4%, and 6 days. In addition, optimal concentrations of the additional ingredients of red pepper powder and crushed garlic for acceptable quality squid Sikhae were both 6%.

• Archives of Reconstructive Microsurgery
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• 제11권2호
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• pp.167-172
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• 2002

The only treatment method for crushed soft tissue injuries in the proximal leg involving the knee joint is the microsurgical free flap transplantation, especially latissimus dorsi myocutaneous free flap is useful to cover the extensive soft tissue defects, therefore prevents iatrogenic below knee amputation and facilitates early wound healing, early ambulation and shortens hospital stay. Authors have treated the open amputation with crushed soft tissue and bone injuries in the proximal leg, and the repeated abrasion and infectious wound with traumatic neuroma in the below knee with myocutaneous free flap and succeeded to wear below knee amputation prosthesis and return to normal activities of the daily living in the relatively shorter period than usual.

• 한국주조공학회지
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• 제22권1호
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• pp.35-41
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• 2002

To improve the reliability of solder joints, a composite solder which consists of solder matrix and intermetallic reinforcements was manufactured by a new method. The cast ingot of Sn-6.9Cu-2.9Ag alloy had primary Cu6Sn5 intermetallics in the form of dendrites. After rolling the ingot, the intermetallic dendrites were crushed into fine particles and distributed uniformly throughout the solder matrix. As the rolled strips became thinner, the average size of the crushed particles reached a critical size which did not decrease any more by further rolling. The critical size was nearly the same as the average width of intermetallic dendrite trunk. The crushed intermetallic particles did not melt and remained in solid state during reflow soldering due to their high meltingterm-perature. The coarsening and gravitational segregation of the particles were observed during reflow soldering.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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• pp.326-327
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• 2018

It is expected that the proportion of crushed aggregate will increase in order to fill the decreasing supply of sea sand in the southeast area. However, it is necessary to supply the least amount of sea sand to diversify the aggregate source, in order to minimize the mixing ratio of sea sand and crushed sand to minimize the structural stability of the concrete.