• 상하수도학회지
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• 제23권1호
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• pp.97-105
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• 2009

Analysis was done on the particle size distribution of sediments flown into Saemangeum from the Mankyung and Dongjin River. The organic pollutants and heavy metal existing in the sediments were analyzed, which was further used to study the properties of pollution in the sediments according to the particle size distribution. Conclusions shown below were made from these analyses. The particle size distribution showed a big difference between the upriver areas of Mankyung and Dongjin River. Particles under $75{\mu}m$ showed to be around 85% at Dongjin River, while it showed to be around 70% at Mankyung River. This kind of distribution in particle size concluded in greatly affecting the contamination density of the sediments. From the analysis done on the soil type of sediments, deposition in Mankyung River categorized into Silty loam and Sandy loam, where Silty loam covered most of area and deposition in Dongjin River categorized into Sand, Loamy sand, Silty loam, Sandy loam. Considering the weight ratio, the density of contamination of the sediments by particle size at Dongjin and Mankyung River has been analyzed to show that organic pollutants and heavy metals occupy more than 70% of the whole contamination in the range under the particle size of $75{\mu}m$.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.322-329
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• 2006

On the way of construction in harbor area, scourin problems took place slowly failure of embankment in the beginning of construction in sites. For studying on the scouring properties during revetment construction in silty sand soil layers, this paper is carried out on lessons of case studies of numerical seepage analysis, scouring countermeasures in dredged landfill area.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.1023-1030
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• 2005

This study is an experiment paper about the ground improvement material which using the waste residual(slag and paper fly ash) by fire. we are research to concern according to the soil to mix the ground improvement material at show strength effectiveness. Also, we can expect a long time strength increase effectiveness as reduce the dryness contraction. They are distinguished to the clay of the reclamation ground and silty sand soil. We examined around an uniaxial compress test and scanning electron microscopy. The uniaxial stress increases according to the increase of the mixed ratio of ground improvement material and the water contents have been reduced the strength value. A clay's improvement effectiveness is big but in the silty sand soil to express small effectiveness. A ground improvement material mixing of the quantity to write can not expect the effect of Ettringite.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2004년도 춘계학술발표회
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• pp.692-697
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• 2004

This study is on the increasement of strength about soft ground improvement material using waste residual(paper fly ash, coke ash, slag) by fire. Through this study the authors have analyzed the strength improvement of mixed soft silty sand with improvement materials. The strength of mixed soils with high mixture ratio and more curing days increased. But CA-30(cokes 60%) make more low strength improvement than others. Therefore the authors find out that paper fly ash+cokes, paper fly ash+slag or cokes+slag improvement material is more effect in improvement of soft silty sand than cokes+cenlent. And Ettringite reaction is free mixed soils with more than two materials.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2001년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall 2001
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• pp.98-106
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• 2001

The deformation characteristics of cohesionless soils in Korea were investigated using resonant column tests. Total 60 samples, which were sampled from sedimentary and residual soils and reconstituted using controlled particle-size distributions, were prepared. The confining pressure applied in the tests ranges from 20 kPa to 500 kPa. The test results ware categorized into 3 groups including clean sands, silt and silty sand, and residual soils. Based on test results, the small-strain shear modulus(G$_{max}$) and damping ratio(D$_{min}$) were determined and the effects of confinement on G$_{max}$ and D$_{max}$ were characterized. The empirical correlations predicting G$_{max}$ were suggested for 3 group soils. Nonlinear deformational characteristics of clean sands are significantly affected by confining pressure and the ranges and mean curves for G and D are suggested considering the range of confining Pressure. The silt and silty sand and residual soils were weakly affected by confining pressure, so the representative ranges and curves, independent of confining pressure, were proposed.d.posed.d.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2001년도 봄 학술발표회 논문집
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• pp.433-440
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• 2001

This study was to analyze characteristics of soils reinforced by FPF(Fibrillated Polypropylene Fiber). Laboratory test, model test and field tests were performed on soils reinforced by fibers, to evaluate the shear strength characteristics. For the silty sand, clayey sand and silty clay, the influence of fiber shape, fiber length and fiber content were evaluated from compaction test, direct shear test, uniaxial test, california bearing ratio(CBR) test. Fibrillated type fiber, 5cm long with a content of 0.5% shows 5∼30% increase of friction angle and 7∼55 percent increase of CBR value.

• 한국지반공학회논문집
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• 제17권5호
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• pp.173-180
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• 2001

이방압밀이 실트질모래의 정적재하에 의한 유동파괴거동에 미치는 영향을 연구하기 위하여 비배수삼축압축시험을 수행하였다. 이를 위하여 상대밀도가 약 17%인 공시체를 습윤다짐방법에 의해서 성형하고 4가지의 압밀응력비, 1.0, 0.7, 0.55, $K_{o}$ 로서 압밀시켰다. 시험결과로서 정상상태선은 p-q 공간상에서 압밀응력비에 관계없이 유일한 직선이며 collapse line의 기울기는 압밀응력비가 증가함에 따라 선형적으로 감소한다는 사실을 보여준다. 또한, 유동파괴거동을 보이는 느슨하게 다져진 실트질모래의 잔류강도($S_{us}$ )와 첨두강도($S^{p}$ )와의 관계는 압밀응력비의 크기에 관계없이 $S_{p}$ /$p_{c}$ = $A_{L}$ +$B_{L}$ ($S_{us}$ /$p_{c}$ )로 표현되는 일반식으로 나타낼 수 있으며 계수 $A_{L}$ 및 $B_{L}$은 압밀응력비의 크기에 따라 선형적으로 변하는 경향을 나타낸다.

• 한국지반공학회논문집
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• 제16권5호
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• pp.37-43
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• 2000

보통으로 다져진 실트질 모래(Dr=50%)에 대한 액상화 전후 상태에서의 반복하중에 의한 동적거동을 연구하기 위하여 몇가지의 압밀응력비로서 압밀시킨공시체에 대해서 일련의 일련의 반복삼축시험을 수행하였다. 연구결과로서 압밀응력비가 액상화거동에 미치는 영향을 나타내었으며 또한 액상화 전후의 동적거동을 비교하였다. 그리고 액상화 후의 거동은 선행액상화시의 응력반전여부에 의해서 절대적으로 좌우된다는 사실을 보여주고 있다. 결론적으로 액상화를 경험한 공시체의 액상화저항은 액상화를 경험하지 않은 공시체에 비해서 이방압밀의 경우에는 높고 등방압밀의 경우에는 낮다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1997년도 가을 학술발표회 논문집
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• pp.285-290
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• 1997

• The Korean Journal of Ecology
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• 제16권2호
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• pp.169-180
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• 1993

Soils of four combinations, sand with high content of organic matter(SL), sand with low content of OM(SS), siltyl loam with high content of OM(LL) and silty loam with low content OM (LS), were filled on column and then percolated with simulated sulfuric acid rain with pH 5.6, 4.0, 3.5, 3.0 and 2.5. From soil leachates, pH and concentrations of basic cations and Al were determined. Cation concentrations in the leachates increased as pH of the rain decreased. The orders of buffering capacity of soil, leachability of cation from soil, leaching sensitivity of ion andbase saturation sensitivity of soil to acidity of the rain water were SS$\leq$K <$\leq$LL