• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2008년도 추계 학술발표회
• /
• pp.1717-1726
• /
• 2008

Vibration triaxial compression test was put in influence for liquefaction strength of fine grained soil of dredged and reclaimed ground and consideration for fine fraction content, relative density, overconsolidation ratio and plasticity index in this study. By the results of these test, the liquefaction strength increased with fine fraction content and the relative density, overconsolidation ratio incresed with liquefaction strength too. However, in the case of nonplastic silt was the smalist liquefaction strength which influenced by dilatancy and interlocking when silt content was 34.7%(average grading 0.12mm). Therefore, liquefaction strength of fine grained soil of dredged and reclaimed ground increased with fine fraction content so it will help to make lower liquefaction.

• 한국산림과학회지
• /
• 제101권3호
• /
• pp.538-545
• /
• 2012

본 연구는 산림유역의 일시하천과 간헐천이 상존하는 수변지역을 대상으로 산림벌채로 인한 토양의 교란 정도를 평가하고, 물리적 수문학적 특성 변화 양상을 파악하였다. 총 12개 소유역에서 4개의 처리구(BMP1, BMP2, 개벌구, 대조구)를 적용하였으며, 각 처리구별 벌채 전 후 1년 동안의 모니터링 결과를 비교 분석하였다. 그 결과, 벌채 후 산정된 교란등급은 벌채강도와 상관이 있는 것으로 나타났으며, 조사된 토양의 물리적 수문학적 특성 변화와 일치하는 경향을 보였다. 그러나, 용적밀도 및 공극률의 변화와는 일치하지 않았다. 전면개벌은 강도 높은 지표교란을 야기 시켰으며, 이로 인해 조공극률 및 투수계수는 감소, 토양강도는 증가하였고, 이는 토양의 침식의 간접적인 원인으로 작용하였다. 개벌구에서 강도 높은 지표 교란으로 야기된 토양의 물리적 수문학적 특성 변화는 BMP1과 BMP2에서 완화되는 것으로 나타났다. 그러나, 벌채 후 BMP2에 남겨진 벌채잔재물은 지표의 피복기능으로서의 침식을 완화하는 효과가 없는 것으로 나타났다.

• The Korean Journal of Ecology
• /
• 제15권4호
• /
• pp.433-449
• /
• 1992

Three horticultural herbaceous plants and a natural herbaceous plant were tested to determine the growth responses, biomass and uptake of cadmium(cd), lead(pb) by application of cd and pb soil treatment in pot culture. The ecological effects on the growth of the plants were investigated to determine the tolerance for the heavy metal pollutants cd and pb. the marginal concentrain of cd treatment on the growth of the each plant was below the 1, 000 ppm treatment of cd. The marginal concentration of pb treatment was below the 1, 000ppm treatment of pb in cultivation of salvia splendens ker., celosia cristata l. and below the 3, 000ppm treatment of pb in cultivation of portulaca grandiflora hook., sedum saramentosum bunge. the resistance for cd of sedum saramentosum bunge, celosia criastata l., portulaca grandiflora hook. and salvia splendens ker. was in the listed order. The resistence for pb was in order of sedum saramentosum bunge, portulaca grandiflora hook. Salvia splendens ker.and celosia criastata l.stems. The flowering of portulaca grandiflora hook. was sustained in the pb 1, 000ppm treated group only. The higher the concentration of pb in the soil cultivated the plants was, the less the content of leaf chlorophy11 in each plant was. The number of stomata per unit leaf area was the highest in salvia splendens ker. and in order of celosia l., sedum saramentosum bunge., portulaca grandiflora hook., the higher the cd and pb concentration of cd and pb treatment was, the more the concent of cd and pb in the part of each plant increased. the content of cd and pb in the stems of salvia spiendens ker. was the highest in the 1, 000ppm-treated ground and in order of the roots, the leaves and the flowers.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2003년도 봄 학술발표회 논문집
• /
• pp.701-708
• /
• 2003

Recently, piezocone penetration test is frequently conformed in order to estimate the characteristics of soft ground with standard penetration test, generally used in the past. The soil characteristics, such as cone penetration resistance, friction resistence and excessive pore water pressure, can be evaluated continuously through the piezocone penetration test. In Incheon International Airport 2nd phase site preparation, standard penetration test and piezocone penetration test were used in order to increase the confidence for determination of soft ground depth. And the compressible layer was determined by the comparison between the preconsolidation pressure and the designed increase pressure. As the results, the relation between standard penetration test and piezocone penetration test shows q$_{c}$=(1.09~l.63)N at the soft ground, determined by 5/30 N value. And q$_{c}$=(1.21~l.98)N was shown at the point of compressible layer, evaluated by the preconsolidation pressure. These results were applied to determination for the depth of soft ground and to design the improvement for the soft clay.lay.