• Journal of the Korean Geotechnical Society
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• v.26 no.6
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• pp.21-28
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• 2010

Decomposed granite soil is the most common type of soils. The measurement of the stress-strain-strength behavior of anisotropic decomposed granite soils is very important for the deformation and stability analysis of slopes, retaining walls, excavations. A series of unsaturated-drained triaxial compression tests were performed to know unsaturated strength properties. The sample had three different angles of the axial (major principal) direction to the sedimentation plane (compaction plane): 0, 45 and 90 degrees. The compression strain of specimens subjected to an isotropic compression was strongly influenced by the sedimentation angle. In addition, the time dependence was independent of the sedimentation angle in relation to the deformation behavior during the secondary compression process. The effect of the sedimentation angle on the triaxial compression strength and deformation was clearly shown with low confining stress. The effect of the sedimentation angle on the compressive strength and deformation was more evident in saturated specimens. A new method of predicting the shear strength of unsaturated decomposed granite soils, considering compaction angles, was proposed.

• Journal of Ginseng Research
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• v.33 no.1
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• pp.13-25
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• 2009

Geochemical relationships between ginsengs and soils from three representative soil types, shale, phyllite and granite regions, from Keumsan were examined. High elements ere shown at the granite and shale areas of the weathered soils, the phyllite areas of he cultivated soils and the shale areas of the host rocks. T1 was enriched in ginsengs grown in the shale areas, Cs and B in the phyllite areas, and Be and Cd in the granite areas. Positive correlations were dominated by the shale areas. These relationships can be explained for mineral characteristics within the soils, and their behaviors related to the physio-chemical conditions. High elements were shown in the 2 year ginsengs of the hale areas, and 4 year ginsengs of the phyllite and granite areas in comparisons with ginsengs of the different ages from the same areas. These differences can be explained with ages of the ginsengs, solubilities of the minerals and physio-chemical differences within soils. The content differences of high elements such as Cs, T1 and Be were found between soils and ginsengs. Overall, these results suggest that components of ginsengs grown in the granite areas are chemically similar to the soils.

• Journal of Ginseng Research
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• v.32 no.4
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• pp.357-381
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• 2008

REEs of ginsengs(2, 3, 4 years) from the granite, phyllite and shale areas, Keumsan, are analysed and compared with the their soils. In the weathered soils, high element contents are shown in the LREE of the granite and in the HREE of the phyllite. The granite dominantly show positive correlation relationships. In the field soils, the phyllite are high while the granite are low. Relationships of the contents and correlation relationships can be explained with mineral assemblages and contents within soils, and their solubilities. In the host rocks, high contents are found in the LREE of the granite and HREE of the phyllite. The rocks dominantly show positive relationships. In the ginseng, high contents are shown in the 2 year for the shale and granite, and the 4 year for the phyllite. Element pairs mainly show positive relationships. Comparing of the same ages, the granite are mainly high. In the ratios between the soils and the ginsengs, differences of the several hundred to ten times are found, but dominantly, of the several hundred times in the shale and phyllite, and of the several ten times in the granite. The differences are big in the 3 year, and small in all REE of the 2 year from the shale and granite. while, in the phyllite, big in the LREE of the 2 year and HREE of the 3 year. Based on the absorption of the leachate by the ginsengs within soils, contents and correlation relationships of the ginsengs from the different soils can be explained with mineral assemblages, solubilities of the constitutional minerals and phyio-chemical affects influenced on the solubility. Of the three different soils, the ginsengs of the granites are chemically more similar to their soils.

• Journal of the Korean GEO-environmental Society
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• v.11 no.6
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• pp.47-55
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• 2010

The recycled fine aggregates were mixed with weathered granite soils typically used for fill materials and tested engineering properties, physical properties, and compaction characteristics according to the mixing ratio of the mixed soils. The results of this study were as follows. For the results of A-type compaction test, the recycled fine aggregates showed low effects compared to the weathered soils, but the mixed soils which were mixed with the weathered granite soils and the recycled fine aggregates showed good compaction effects. Especially, the mixing ratio of 70:30 by weight showed for maximum compaction result. From the results of the direct shear test, the cohesion was ince csed according to proportion of the weathered granite soils. The weathered granite soils neared the optimum moisture content showed for maximum shear strength paramcoers, while the cohesion of the mixed soil was relatively ince csed in the wet side of the optimum moisture content. This trend was seemed to remained cence composition in the recycled fine aggregates. The internal friction angle of the recycled fine aggregates and the mixed soils showed maximum value near dry side of the optimum moisture contents. And the internal friction angles of the mixed soils were increased according to higher proportion of the recycled fine aggregates.

• Magazine of the Korean Society of Agricultural Engineers
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• v.26 no.3
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• pp.81-89
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• 1984

To examine the moisture adsorption and permeability characteristics, weathered granite soils of different degrees of weathering, cultivated upland soils and sands of Han-river were sampled. The results are as follows: 1. In case that the mother rock was same, the pF values under same moisture content decreased according as the grain size of soil became finer by the weathering process. 2. In case that the mother rock was different, the pF value varied by the behavior of clay minerals, and the cultivated upland soils showed more sensitive reaction than sands and fresh granite soils. 3. The pF value changed by the difference of primary moisture content and also influenced by soil structure, testing method and etc. 4. The pF value and compaction curve had close relation, however under same moisture content, the pF value decreased by the increment of density. 5. The permeability depend on the available void ratio between the soil particles according to the degree of weathering, and the pF value of available void water between the soil particles which related directly to permeability was about 3.3 except the void water holded in the soil particles. 6. As the above, the pF value and permeability were differentiated by degree of weathering, primary moisture content, density and etc. Therefore it is considered unreasonable to define uniformly by soil texture.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.884-889
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• 2005

A lot of landslides were occurred in Gangnung, Macheon and Geochang areas by Typhoons such as RUSA(2002) and MEAMI(2003). Soil properties of these areas are investigated regarding geological conditions in this study. The shallow plane failure were occurred in Gangnung and Geochang areas, whereas the deep circle failure were occurred in Macheon area. The matrix in Gangnung and Geochang areas was composed of Granite, and the matrix in Macheon area was composed of Gabbro. The disturbed and undisturbed soils were sampled in these areas. As the results of laboratory tests using sampled soils, the coefficient of permeability in Granite region is lower than that in Gabbro region. In the cases that the silt and clay contents are included less than 4% for the soils of Granite region and less than 7% for the soils of Gabbro region, the coefficients of permeability are rapidly increased for both soils. In addition, the simple equations for predicting the coefficients of permeability are proposed using the effective particle size and the silt and clay contents according to geological condition.

• Journal of The Korean Society of Agricultural Engineers
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• v.51 no.1
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• pp.11-20
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• 2009

Flow pump technique was used in order to determine the soil-water characteristic curve of weathered granite soils in Pocheon area. This technique enables measurement to be more convenient and accurate as it is based on the CU condition of triaxial compression test. Besides, it is also able to measure dry and moisture curves continuously since the test is controled by means of a computer automatically. In this study, not only a hydraulic conductivity of weathered granite soils at fully saturated state in Pocheon area, but also a soil-water characteristic curve throughout unsaturate flow tests were determined. In addition, Brooks and Corey's model and Genuchten's model were used to simulate the soil-water characteristic curve. On the basis of the simulation an unsaturate hydraulic conductivity was predicted.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.784-791
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• 2008

This study is to evaluate the characteristics of bearing capacity for granite soils by N-value. The partial data is investigated for practical evaluation of weathering degree and bearing capacity on granite soils. The settlement is linearly decreased when the N-value is less than 50, but the settlement isn't constant when the N-value is more than 50. This is the affect of ground water. Therefore ground water is detailed evaluated. The bearing capacity is linearly increased when the N-value is less than 30, is inactively increased when the N-value is between 30 to 50, is constant when the value is more than 50.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2002.10a
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• pp.341-344
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• 2002

This study, soil sampling includes disturbed weathered granite soils from 8 different sites and disturbed weathered non-granite soils from 5 sample sites, put a purpose on finding for a utility possibility and practical use in this study. As a result of this study, internal friction angle & cohesion indicate which are from re-mold of samples by compaction seem to be able to use a compared to an field data. It is considered that strength parameter of disturbed weathered granite soil in the field is a useful reference.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.211-214
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• 2003

This study, soil sampling includes disturbed weathered granite soils from 8 different sites and disturbed weathered non-granite soils from 5 sample sites, put a purpose on finding for a utility possibility and practical use in this study. As a result of this study, internal friction angle & cohesion indicate which are from re-mold of samples by compaction seem to be able to use a compared to an field data. It is considered that strength parameter of disturbed weathered granite soil in the field is a useful reference.