• Journal of the Korean Geosynthetics Society
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• v.16 no.2
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• pp.159-164
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• 2017

This paper presents the results of an investigation into the thermo-hydromechanical response of weathered granite soil. The effect of forced change temperature and relative humidity at the soil layer boundaries were monitored during heating. A series of load settlement test were performed on layers of compacted, unsatureated weathered granite soil with geosynthetic embedded at mid height before and after application of heat exchanger to the base of the soil layers. The results from this study indicated the potential for using embedded heat exchangers for the mechanical improvement of geotechnical systems incorporating weathered granite soil.

• Geomechanics and Engineering
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• v.38 no.4
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• pp.335-352
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• 2024

Low carbon energy demand in South Korea is increasing, hence leading to an increasing usage of wood pellets and the amount of its combustion by-product called wood pellet fly ash (WA). In an effort to develop recycling technology, this research investigates the use of WA as a new sustainable binder for backfill soil materials. The influence of WA on weathered granite soils (WS) is investigated by mixing 5%, 15%, and 25% of WA dosage, compacted at optimum moisture content, then cured for 3, 7, 14, and 28 days. After curing, the compacted specimens were investigated through unconfined compressive tests, pH tests, total suction tests, and microstructural analysis. The findings suggest that the higher the dosage rate, the higher strength and modulus. Additionally, the alkali ions of WA aid in the cementation of WS particles, and newly cementitious minerals are confirmed after 28 curing days. The refinement of pore microstructures led to a denser WS matrix and stiffness improvements. The results validate the binding potential of wood pellet fly ash on weathered granite soils in terms of strength, modulus, and microstructures.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.10
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• pp.2810-2818
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• 2009

In order to examine the characteristic of shallow failure in cut slopes composed of weathered granite soil, this study calculated critical permeability coefficient according to rainfall characteristic in Korea, performed stability analysis according to the representative physical properties of weathered granite soil distributed in Korea such as horizontal distance to the failure surface of cut slope, slope inclination, slope height, and the depth of wetting by rainfall, and analyzed the results. In the results of analyzing critical permeability coefficient, when the local rainfall characteristic was considered, the maximum critical permeability coefficient was $7.16{\times}10^{-4}cm/sec$. We judged that shallow failure according to wetting depth should be considered when rainfall below the critical rainfall intensity lasts longer than the minimum rainfall duration in cut slopes composed of weathered granite soil, which had a critical permeability coefficient lower than the maximum critical permeability coefficient. Furthermore, using simulated failure surface, this study could understand the characteristic of shallow failure in cut slopes based on the change in slope safety factor according to horizontal distance, wetting depth, and strength parameter.

• Advances in concrete construction
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• v.9 no.6
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• pp.537-545
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• 2020

In order to reduce the usage of cement slurry in grouting engineering and consume the tunnel excavation waste soil, a new geopolymeric grouting material (GGM) was prepared by combine completely weathered granite (CWG) and blast-furnace slag (BFS), which can be applied to in-situ grouting treatment of completely weathered granite strata. The results showed CWG could participate in the geopolymerization process, and GGM slurry has the characteristics of short setting time, high flowability, low viscosity, high stone rate and high mechanical strength, and a design method of grouting pressure based on viscosity evolution was proposed. By adjusted the content of completely weathered granite and alkali activator concentration, the setting time of GGM were ranged from 5 to 30 minutes, the flowability was more than 23.5 cm, the stone rate was higher than 90%, the compressive strength of 28 days were 7.8-16.9 MPa, the porosity were below 30%. This provides a novel grouting treatment and utilizing excavated soil of tunnels in the similar strata.

• Journal of the Korean Geotechnical Society
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• v.37 no.6
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• pp.21-28
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• 2021

The factors of landslides depend on rainfall intensity, duration, and the characteristics of the soil slope. The conventional slope stability analysis has been carried out by assuming that the slope is saturated. But, a site slope consisting of unsaturated ground must be imitated and interpreted in order to explain a proper behavior of the slope due to rainfall. In this study, by using two major categories of soils in Korea, such as granite and gneiss weathered soils, landslide model test and numerical analysis have been compared with the difference of seepage and volumetric water content. In general, the permeability of gneiss weathered soil, which contains a lot of fines content, is slower than that of granite weathered soil. As a result, in extreme rainfall, numerical analysis can show results that can penetrate quickly, resulting in saturation or more dangerous collapse.

• Geotechnical Engineering
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• v.9 no.2
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• pp.5-14
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• 1993

Weathered granite soil is the most representative as a surface soil in Korea. In this paper, the dynamic properties and settlement characteristics of Korea granite soil are studied through the dynamic triaxial compression tests. The dynamic characteristics are very important on the analysis of the foundations under dynamic loading such as machine vibration and earthquake. Soil samples having different grain sixtes were prepared at the relative densities between 80oA and 90oA and tested to measure shear moduli and damping ratios at each level of shear strain. The measured shear moduli of weathered granite soils showed large variations according to the grain sizes, confining pressures, relative densities and shear strains. Sandy weathered granite had a little larger dynamic properties than the average values of the sand studied by Seed and Idriss. Pot the well compacted granite soils, little residual settlements occured due to dynamic loading.

• Journal of Ginseng Research
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• v.29 no.4
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• pp.192-205
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• 2005

This study is for geochemical relationships between ginsengs and soils from three representative soil types from Keumsan, shale, phyllite and granite areas. For this study, ginsengs (2, 3 and 4 years), with the soils and their host rock, are collected and are analysed for the transitional elements. In the weathered soils, the shale area is high in the most of elements, but low in the granite area. High correlation relationships are shown in the shale area. In the field soils, the shale area is mainly high, but low in the granite area. Comparing with ages, most of elements are high in the 2 year soils, but low in the 4 year soils. Regardless of the localities, positive and negative correlations are dominant in the shale area. In the host rocks, high element contents are shown in the phyllite and shale areas. Positive and negative correlations are found in the shale and phyllite areas for large numbers of the element pairs. In the ginsengs, differences of the element contents with ages are not clear, but show high element contents in the 2 year ginsengs of the shale and phyllite areas, and low contents in the 4 year ginsengs of the granite area. Positive correlations are shown in the Cu-Zn pair in the shale and phyllite areas, and Co-Cu pair in the granite area. In the relative ratios(weathered soil/field soil), most of elements from the shale area are high, above I, suggesting high element contents in the weathered soils of the shale area relative to the granite and phyllite areas. In the relative ratios(weathered soil/host rock), most of elements are above 1, suggesting the high element contents in the weathered soils relative to the host rocks. Relative ratios (soil/ginseng) of the element contents are several to ten times. Regardless of the areas, big differences of the relative ratios are found in the Co and small differences are in the Cu and Zn, which suggest that differences between soils and ginsengs are big in the Co contents and small in the Cu and Zn contents. Regardless of the ages, differences among relative ratios are small in granite area relative to the shale area, which suggest more similar contents between ginsengs and soils in the granite areas.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.03b
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• pp.548-555
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• 2000

It was investigated whether the waste polyethylene chips can be recycled as construction materials in geotechnical engineering field. The standard Proctor test, the hydraulic conductivity test, the large box direct shear test, the thermal conductivity test, the frost heaving test and the time domain reflectometry test were performed on weathered granite soil mixed with variable amount of the waste polyethylene chips. The experimental results showed that the hydraulic conductivity and the shear strength of weathered granite soil increase with increasing the amount of the waste polyethylene chips. On the other hand, the thermal conductivity, the amount of frost heaving and the unfrozen water contents of weathered granite soil decrease with increasing the amount of the waste polyethylene chips.

• Magazine of the Korean Society of Agricultural Engineers
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• v.44 no.1
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• pp.103-115
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• 2002

During this study, various stress path tests in previous isotropic and anisotropic (compression and tension) stress histories are performed on weathered granite soil sampled at Iksan, Jeonbuk. Yielding points are determined from various stress-strain curves(stress ratio-shear strain, volumetric strain, normalized energy and dissipated total energy curves). The shape and characteristics of isotropic and anisotropic yielding curves are examined. The main results are summarized as follows . 1) Yielding curries defined from stress ratio - normarized energy and dissipated total energy curves show almost perfect ellipse. 2) Directions of plastic strain incremental vector are not perpendicular to yielding curve. 3) Normarized energy and dissipated total energy spread with similar tendency with respect to yielding currie in stress space.

• Magazine of the Korean Society of Agricultural Engineers
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• v.41 no.2
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• pp.80-91
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• 1999

This paper presents the stress-strain , volumetric strain characteristics of the Pocheon weathered residual granite soil with variation of the initial water content under drained conditions. A series of consolidated drained triaxial compressiion tests and isotrpc compression tests with various initial water content on specimens were performed. All material parameters of Lade's double work hardening model were determined by using the results of tests. Most aspects of the soil behavior measured in the triaxial compression tests were reproduced with good accuracy by the constitutive model . Therefore double work hardening model has been shown to be applicable to weathered residual granite soil.