• Proceedings of the Korean Geotechical Society Conference
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• 2000.11a
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• pp.17-24
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• 2000

Hardening agent has been the traditional material for surface soil stabilization of soft ground. This study aims at determining optimal mixture ratio of hardening agent in accordance with the required design specifications. Hardening agent is properly mixtured with Fly ash, Gypsum, Slag and Cement for the ettringite hydrates which is effective for early stabilization of unconsolidated soil. The treated soil is the clay which are widely found here and there in Korea. In this study, preliminary tests were performed to get optimal mixture ratio of stabilizer ingredient, and marine clay in Jin-Hae was used to get physical and chemical properties. Laboratory tests of 50 stabilized soil were peformed to get optimal mixture ratio for 16 stabilizer material of 6 type, and stabilizer mixing was determined.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.1237-1244
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• 2006

This research discussed about method for basis construction of sea jacket construction. Several access ways of method for foundation construction of sea jacket construction are used. Accompany many efforts of design and build process to overcome the form of construction work and application equipment, special quality of construction and restriction and so on of sea environment in the case of pile foundation. Therefore, great many factor of sea condition, construction special quality, base condition, construction time, equipment composition, worker composition etc. shows other work form in spot at sea jacket construction process.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.687-696
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• 2006

Slope failure triggered by rainfall produces severe effects on the serviceability and stability of railway. Therefore slope stability problem is one of the major concerns on the operation of railway. In this study we collected rainfall data when and where slope failures were observed. The collected data show that the range of cumulative rainfall is from 150 to 500mm and the rainfall duration is about 3 to 24 hours. By using the collected rainfall information, slope stability analysis considering infiltration was carried. The analyses employs multiple sliding surfaces to find the minimal factor of safety in the infinite slope condition. This approach show more reasonable results than the results from analysis following the design code which assumes that groundwater level and the slope surface are equal.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.1120-1125
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• 2006

Larger area will be constructed in a harbor land and container terminal which are constructed in reclaimed land using the dredged materials. Soil improvement work is to be carried out including constructibility, in which is monitoring devices, measuring frequency, installations etc. The ground water tables in the reclaimed area are affected by the several factors which are design reclamation level, consolidation settlement, remaining surcharge pressure and remaining excess pore water pressure. The plan wii be drawn up in which monitoring results for the ground water tables are capable to provide the reliable ground water table when designers and civil engineers construct the harbor structures considering constructibility.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.794-799
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• 2006

For various historical reasons and some technical reasons, the safety of dams has been controlled by an engineering standards-based approach, which has developed over many years, initially for the design of new dams, but increasingly applied over the past few decades to assess the safety of existing dams. And some countries were asked for risk assessment on existing dam, which included structural, hydraulic safety of dam and social risk. So, Many countries were developed and could be adapted as an additional tool to assist in decision-making for dam safety management.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.61-68
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• 2006

Cemented Sand and Gravel(CSG) is a material made by simple mixing of rock-based raw materials such as excavated soil and riverbed gravel together with cement and water. The use of CSG methodl for cofferdam and large dam is gradually increasing in Japan because a quarry and aggregate plants can be diminished. Also, the CSG method can reduce dam construction cost, construction duration and destruction of environment. In this paper, field test and test construction of CSG method was conducted on Hwabuk Dam. The mechanical properties of CSG, such as compressive strength, extention strength and field permeability test were investigated. From the results of the experimental study, application study of CSG method was discussed.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.824-827
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• 2006

The Prefabricated Vertical Drains (PVDs) method is one of the most widely used techniques to accelerate the consolidation process in-situ and hence increase its bearing capacity. In this paper, the degree of consolidation incorporated with PVDs was evaluated in O construction work site which composed with dredged soil. O Program PVD(Version 2.3) which developed by Asian Institute of Technology was used. The purpose of this analysis is efficiently to estimate the degree of consolidation by analyzing the surface settlement with time, and drainage at initial stage and final stage by using design-parameter which based on the in-situ tests and laboratory tests. This result can be compared with analysis of the degree of consolidation using Program PVD(Version 2.3) and the field observed data in the future studies.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.1369-1376
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• 2005

In case of the drainage type tunnel, the residual water pressure is likely to act on the tunnel lining due to the decrease of water-passing capacity of the filter material. Therefore, this study discussions a method to predict the lining load with the consideration of water passing capacity of the filter material through the literature review and numerical analysis. It is expected from the results of case studies that the design load acting on the concrete lining in the drainage type tunnel could be assumed to be about 50% of the hydrostatic water pressure in steady-state ground-water condition.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.966-973
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• 2005

The stress concentration ratio in accordance with area replacement ratios were considered as core elements of design. However, the stress concentration ratio will be vary depends on progress of consolidation in clay ground. And, since it is not sure to know the affecting factors accurately, the value is decided based on field experiences. To use SCP method more effective and correspond to soil improvement, the decision on proper area replacement ratio through the exact stress concentration ratio is very important. Accordingly, a numerical analysis on influence of various factors that needed to make rational designing guide for decision of proper area replacement ratio to stress concentration ratio was executed in this study.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.1245-1251
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• 2005

The deformation modulus is an important variable which can be used to predict settlement of structures, analyze horizontal directions of piles and design roads. Though to predict deformation modulus relationships using standard penentration test N-value and undrained shear strength were suggested , these relationships are not appropriate in domestic areas because these relationships are based on foreign areas. Therefore, in this study, with field test results, reasonable equations in domestic area are suggested to estimate deformation modulus.