• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.299-307
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• 2009

New lake dike in Saemanguem area is 125km length and require a great amount of fill materials, but it's difficult to get the amount of materials and develop a quarry because of environment conservation. Therefore, the solution is to use the dredged soil in project area as the fill materials not to develop quarry. However, characteristic of dredged soil as a silty fined sand is very weak at seepage, sliding, erosion of dike due to infiltration of rainfall, wind etc. So, lake dike using dredged soil must be constructed safely against the unstable problem of dredged sand. The objective of research is to make safe lake dike using dereged soil on construction of Saemangeum new lake dike. So, we analyzed the characteristic of dredged soil and suggested a standard section of lake dike.

• Journal of the Korean Geotechnical Society
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• v.17 no.4
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• pp.49-55
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• 2001

본 논문에서는 서해안 폐기물 매립지 하부의 점성토와 고화차수재를 재료로 수행된 확산시험 결과와 현장 조건을 적용하여 오염물이동성에 대한 수치해석을 수행하였다. 무기화합물이 하부 차수재와 원지반퇴적층으로 이동되는 일차원 이동 특성을 대상으로 하였으며 일차원 용질이동해석 프로그램 CDFD(convection-dispersion finite difference)를 현장의 비균질한 지층에 이용할 수 있도록 수정하여 적용하였다. 그 결과 원지반점성토를 통한 용질이동 메카니즘에 확산이 기여하는 정도가 50%로 매우 큰 영향을 갖고 있음을 보여주며 원지반 투수계수가 클수록 인공차수층의 필요성이 증대됨을 알 수 있었다.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.357-364
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• 2002

This paper describes the feasibility of compacting subgrade layer in thicker lifts than currently permitted as 20 cm. This project involved constructing and testing a full scale test section in highway. Soil stiffness in field was evaluated by a nondestructive testing method, called Geogage. Quality control tests and FE Analysis were also conducted. Typical dynamic compaction roller of 11ton weight is applied for full scale test and a Mohr-Coulomb model and Plane strain condition are used for FE Analysis. The results showed that compaction-induced stress and dissipated energy are mainly depend on depth of soil and it could be possible to increase thickness of a lift.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.2
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• pp.219-223
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• 2006

In this paper, the criteria of the lateral displacement in soft soil due to embankment were evaluated. The lateral displacement was measured at a pier structure in a new harbor construction site, and the measurement was compared with the criteria. The results by the measurement such as the critical pressure causing lateral movement in terms of undrained strength, the lateral movement index by Japan Highway Co., the lateral displacement index by Japan Construction Ministry, the modified index by Korean Highway Co. were estimated to be lower than the respective index values.

• Journal of the Korean Geotechnical Society
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• v.24 no.4
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• pp.79-88
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• 2008

Recently, the high speed railway comes into the spotlight as the important and convenient traffic infrastructure. In Korea, Kyung-Bu high speed train service began in bout 400 km section in 2004, and the Ho-Nam high speed railway will be constructed by 2017. The high speed train will run with a design maximum speed of 300-350 km/hr. Since the trains are operated at high speed, the differential settlement of subgrade under the rail is able to cause a fatal disaster. Therefore, the differential settlement of the embankment must be controlled with the greatest care. Furthermore, the characteristics and causes of settlements which occurred under construction and post-construction should be investigated. A considerable number of studies have been conducted on the settlement of the natural ground over the past several decades. But little attention has been given to the compression settlement of the embankment. The long-term settlement of compacted fills embankments is greatly influenced by the post-construction wetting. This is called 'hydro collapse' or 'wetting collapse'. In spite of little study for this wetting collapse problem, it has been recognized that the compressibility of compacted sands, gravels and rockfills exhibit low compressibility at low pressures, but there can be significant compression at high pressures due to grain crushing (Marachi et al. 1969, Nobari and Duncan 1972, Noorany et al. 1994, Houston et al. 1993, Wu 2004). The characteristics of compression of fill materials depend on a number of factors such as soil/rock type, as-compacted moisture, density, stress level and wetting condition. Because of the complexity of these factors, it is not easy to predict quantitatively the amount of compression without extensive tests. Therefore, in this research I carried out the wetting collapse tests, focusing on various soil/rock type, stress levels, wetting condition more closely.

• Korean Journal of Agricultural Science
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• v.30 no.2
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• pp.164-174
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• 2003

This study was performed to suggest a rational method for the stability evaluation of agricultural reservoir in the very soft ground. The stability methods for agricultural reservoir was used to compare and analyze with various condition by limit equilibrium method. The behavior of settlement-displacement obtained by field monitoring system was used to compare and analyze with various stability methods, and to investigate the applicability of the methods for stability evaluation of agricultural reservoir. The horizontal displacement was abruptly increased when physical properties of soft clay reached its maximum values and therefore, the values of these properties could be used to the fundamental data for stability evaluation. The evaluation of the stability of agricultural reservoir was suggested to use the inclination of curve rather than critical line.

• Journal of the Korean Geosynthetics Society
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• v.14 no.1
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• pp.51-58
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• 2015

The counter weight filling is a technology to accumulate soils on the side of berm with a proper width and height for improving the stability of the embankment. This study aims to assess a feasibility of the counter weight filling in the construction of pavement roads for recovery of shear failure during the construction. An effective counter weight filling section was suggested using the numerical analysis. The results showed that the effective counter weight filling section is two-fold (x2) higher than the ratio of width in counter weight filling : embankment height and one third (1/3) to the ratio of height in counter weight filling : embankment height. Also a range of effective trench crossing the counter weight filling required when a trench crossing counter weight filling is installed was suggested by supplying a proper distance between the counter weight filling section and cross-sectional trench.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.252-252
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• 2015

우리나라에서는 대하천정비사업을 통해 주요 국가하천마다 보와 제방을 신설 및 보축하여 홍수의 방어 및 예방에 힘을 기울이고 있으며, 근래에는 이러한 정비사업이 완료되어 가고 있는 상황이다. 제방에 대한 정비사업의 내용은 보축 및 신설이 주를 이루나, 제내지의 성토와 제외지의 보강 및 저수로의 준설 등도 함께 수행되었다. 이러한 정비사업의 영향으로 지하수 및 하천의 흐름양상은 정비사업 전과는 다르게 변화 될 것으로 추정되며, 이는 제방 안정성에 영향을 줄 수 있는 중요한 문제로 판단된다. 따라서, 이와 같은 지하수 및 하천흐름의 변화양상이 제방의 안정성에 얼마나 영향을 미칠 수 있는지 정량적으로 분석할 필요가 있을 것으로 보인다. 특히, 대하천정비사업으로 지반누수를 방지하기 위한 제내지 성토나 퇴사제거를 위한 하천준설 등이 수행되면서 제방의 외적인 환경들이 많이 변하게 되었으나 이에 대한 정량적인 연구들이 거의 수행되지 않은 것으로 판단된다. 따라서, 본 연구에서는 낙동강과 회천 합류부에 위치한 율지제를 대상으로 이곳에 설치된 간극수압계의 데이터와 2차원 침투해석 프로그램인 SEEP/W를 이용하여 제내지와 제외지 표고변화에 따른 파이핑 안정성을 분석하였다. 그 결과 제내지 표고가 상승하면 파이핑 안전율이 증가하고 표고가 하강하면 안전율은 감소하는 것으로 나타났다. 한편, 제외지의 표고변화는 제방안정성에 거의 영향을 주지 않으며 오히려 하천수위의 영향을 지배적으로 받는 것으로 판단된다. 따라서, 제방안정성을 확보하기 위해서는 기초지반의 경우, 제내지측을 상승시키고 하천수위를 하강하는 것이 효과적일 것으로 판단된다.

• Journal of the Korean Geosynthetics Society
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• v.9 no.4
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• pp.27-37
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• 2010

Woven geotextiles (polyester mats) reinforcement is generally used to improve traffic ability, bearing capacity, and slope stability for embankment construction on soft ground. Cases of two high-strength woven geotextiles reinforcement layers are introduced in the present paper, which has been successfully constructed for rail road embankment on soft ground. According to the case results based on the limit equilibrium analyses of slope stability, the two high-strength woven geotextiles reinforcement layers on the soft ground can substantially increase the stability of the embankment by about 25%, improve the safety factor from 0.91 to 1.14, and significantly reduce the embankment construction duration at least 2 months. Therefore, the application of high-strength woven geotextiles is found to be useful for in-situ cases having the lack of construction duration and stability, as a soft ground improvement.

• Journal of the Korean Geotechnical Society
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• v.18 no.5
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• pp.27-35
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• 2002

To construct pipe lines, culverts, or other utility lines, temporary slopes formed by excavating the compacted embankment are frequently met with in the field. Ignoring stability analyses for such slopes and applying inappropriate slope inclinations often result in safety problems. In this study, stability of such slopes were investigated considering the influence of anisotropic shear strength of the layered compacted ground. A series of stability analyses were conducted for slopes varying the slope angle and the height, and assuming isotropic and anisotropic shear strength conditions, respectively. The anisotropic shear strength of the compacted soil was determined from the direct shear test for layered soil blocks varying the inclination angle between the horizontal shear surface and the direction of the soil layer. As a result of the analyses, it has been concluded that the appropriate slope inclination f3r a temporary slope could vary in accordance with the consideration of anisotropy. However, the factor of safety as well as the location of the failure surface did not show significant variation.