• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.467-472
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• 2010

Individual vacuum pressure method is soft ground improvement technique, in which a vacuum pressure can be directly applied to the vertical drain board to promote consolidation and strengthening the soft ground. This method does not require a surcharge load, different to embankment or pre-loading method. In this study, given the inner displacement of the ground where the individual vacuum pressure is applied, this dissertation aimed to reproduce the state of stress in the ground that is subject to the constraints created by the depth of improvement area. Modified Cam Clay theory which made it possible to take into account the isotropic displacement of the ground was applied to the NAP-IVP used simulation; the conception of equivalent permeability proposed by Hird was also applied so that the 3-dimensional real construction effect of drain materials could be reflected in the analysis.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 가을 학술발표회 논문집
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• pp.217-222
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• 2000

An understanding of the behaviour of soft clay soils is important in a large number of civil engineering applications, including dredging operations, land reclamation and slurry management such as disposal and storage. Although the details of the behaviour depend on parameters such as the soil mineralogy, the pore water chemistry, the organic content and the microbiology, there are general features that are typical in many cases. The purpose of this paper is to present and discuss some of evaporation and desiccation observed in laboratory experiments under controlled conditions. Desiccation of dredged material is basically removal of water by evaporation which is controlled by weather and material type, etc. This study shows that (1) solar radiation, (2) wind velocity, (3) material depth, (4) trench depth are important factors in desiccation of dredged ultra soft clay.

• 한국항만학회지
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• 제12권2호
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• pp.337-348
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• 1998

Since 1970s, though many effective construction methods have been established to solve soft ground problems which had occurred in the off shore land reclamation and on shore highway construction, lateral movement of structure on soft ground is still a big problem to engineers. In this study an applicability of criteria for determining the lateral movement of the structure in soft ground is examined and most measured data is obtained from 140 bridge abutments in highway construction sites. Characteristics and effectiveness of existing methods that used for deciding amount of lateral movements of abutment are analyzed using the obtained data. From the analysis, a proper method to prevent lateral movement is proposed. This method is confirmed on several case histories which were constructed on marine clay.

• 한국지반신소재학회논문집
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• 제6권4호
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• pp.15-20
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• 2007

최근 경제가 성장함에 따라 산업지역과 거주지의 요구가 증가하고 있다. 그러나 양질의 지반상태 지역을 구하기가 어렵다. 경제적이고 균형적인 지역 발전을 위하여 내륙지역 뿐만 아니라 연약지반에도 새로운 프로젝트가 수행되고 있다. 연약지반은 복잡한 공학적 특성과 강도가 낮고 대상 지역의 심도가 깊은 많은 변수를 가지고 있기 때문에 연약지반의 공학적 특성을 정확하게 분석하고 안정적인 계측과 경제적인 설계와 관리방법을 찾는것이 필요하다. 연직배수공법은 프리로딩과 통수능력을 가진 여러 종류의 배수재를 사용하여 연약지반과 퇴적지반의 압밀촉진을 위하여 많이 사용되고 있다. 본 논문에서는 6가지 코어형태의 연직배수재의 대형통수능력 시험을 수행하고 시간 경과에 따른 통수능과 압밀도를 분석하였다.

• 한국지반신소재학회논문집
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• 제7권1호
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• pp.39-44
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• 2008

최근 경제가 성장함에 따라 산업지역과 거주지의 요구가 증가하고 있다. 그러나 양질의 지반상태 지역을 구하기가 어렵다. 경제적이고 균형적인 지역 발전을 위하여 내륙지역 뿐만 아니라 연약지반에도 새로운 프로젝트가 수행되고 있다. 연약지반은 복잡한 공학적 특성과 강도가 낮고 대상 지역의 심도가 깊은 많은 변수를 가지고 있기 때문에 연약지반의 공학적 특성을 정확하게 분석하고 안정적인 계측과 경제적인 설계와 관리방법을 찾는것이 필요하다. 연직배수공법은 프리로딩과 통수능력을 가진 여러 종류의 배수재를 사용하여 연약지반과 퇴적지반의 압밀촉진을 위하여 많이 사용되고 있다. 본 논문에서는 폐석회 지반에 2가지 형태의 연직배수재를 적용하여 통수능력 분석하였다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.932-939
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• 2005

Recently, the lateral displacement of the passive piles which installed under the revetment on soft ground is very important during the land reclamation work along the coastal line. The revetment on the soft clay develops the lateral displacement of the ground when the revetment loading is exceeded a certain limit. The lateral displacement of ground causes an excessive deformation of under structure itself and develops lateral earth pressure against the pile foundation as well. Especially passive piles subjected to lateral earth pressures are likely to have excessive horizontal displacement and large bending moment, which induces structural failure of pile foundation and harmful effects on superstructure. The subject of study is to investigate the later displacement of pile foundation during the construction of container terminal at the south port of Incheon. Actual field measurement data and finite element method(FEM) by AFFIMEX Ver 3.4 were used to analyze the displacement of pile and the vertical settlement of soft ground. This analysis was carried out at each sequence of construction work.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.445-454
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• 2006

Myungji Housing Complex is located in the Nakdong River plain in which the Busan soft clays are developed. It has thick soft soil laver of about GL(-)50m including loose sandy layers, upper and lower clayey layers. The clayey layers have been being consolidated since the land reclamation was completed to build the place for Housing Complex(Apartment) in 1997. Therefore, as one of a series of advance preparations of this project, study was carried on the geotechnical characteristics under the foundation The first part of this paper represents a brief geological history. Then, geotechnical characteristics of clay was analyzed in the classical developments in soft clay. They were based on the geotechnical data obtained by site investigations performed from 1992 to 2005. Finally, we evaluated the average degree of consolidation at this point in time and the residual settlements of upper clayey layer using dissipation and oedometer tests for this project

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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• pp.318-326
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• 2008

Recently, a new seismic probe, called "MudFork", has been developed and can be utilized for accurate and easy measurements of shear wave velocities of soft soils. To expand its use to estimate undrained shear strength and density, correlations between those and shear wave velocity were being attempted. Cone penetration tests and a seismic test, using MudFork, were performed at a soft ground site near Incheon, Korea. Also, undisturbed samples were obtained and shear wave velocities of the samples were measured as well as undrained shear strength, using triaxial compression test and bender elements. A simple linear relationship between shear strength and shear wave velocity was obtained, and a tentative relationship between density and shear wave velocity was also defined.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.1241-1244
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• 2005

In this case study, the field investigation work on soft soils like a reclamation area with dredged-clay or intertidal mud flat which has not enough strength to resist the load of surveying machines, the amphibious barge(modified AMFIROL) which travels on land and water was adopted to the field investigation work. Despite of slight increase of cost, it was found that the adoption of amphibious barge in field investigation could improve the quality of test results and avoid the waste of time and some effort.

• 토지주택연구
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• 제11권2호
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• pp.87-94
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• 2020

Offshore renewable energy resources are attractive alternatives in addressing the nation's clean energy policies because of the high demand for electricity in the coastal region. As a large portion of potential resources is in deep and farther water, economically competitive floating systems have been developed. Despite the advancement of floating technologies, the high capital cost remains a primary barrier to go ahead offshore renewable energy projects. The dynamically installed piles (DIPs) have been considered one of the most economical pile concepts due to their simple installation method, resulting in cost and time-saving. Nevertheless, applications to real fields are limited because of uncertainties and underestimated load capacity. Thus, this study suggests the appropriate analytical approach to estimate the inclined load capacity of the DIPs by using the upper bound plastic limit analysis (PLA) method. The validity of the PLA under several conditions is demonstrated through comparison to the finite element (FE) method. The PLA was performed to understand how flukes, soil profiles, and load inclinations can affect the inclined load capacity and to provide reliable evaluations of the total resistance of the DIPs. The studies show that PLA can be a useful framework for evaluating the inclined load capacity of the DIPs under undrained conditions.