• Magazine of the Korean Society of Agricultural Engineers
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• v.21 no.3
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• pp.92-103
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• 1979

The compaction of core zone of the fill dam is very important foe increasing of the Strength of soil mass and reduction of permeability of the core. The principal objects of this study are to give the construction criteria of tamping rollers and to find out the relationships between density and permeability of soil after compaction. The results in this study are summarized as follows. 1. The core zone of fill dam should be compacted more than 8 passed because the compaction effects of clayey soil increase sharply in about 8 passes of roller. 2. The coefficient of permeability (K) increases with the thickness of compaction of soil even though the density is same. 3. The effect of compaction increases with the quantity of coarse materials such as coarse sand and gravel. 4. If D values change from 100 percent to 98 percent and from 100 percent to 95 percent, K values become 2 times and 5 times of initial K value respectively. 5. The coefficient of permeability in the field soil is very high comparing with the result of laboratory test at the same 100 percent compaction ratio, but differences between both results decrease with the decrease of compaction ratio. 6. Thickness of soil layer for the compaction should be increased for heavier compaction machine. 7. In order to get the compaction ratio of 98 percent or more, 10 to 12 passes of roller is generally required with the thickness of soil from 20cm to 30cm.

• 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.

• The Journal of Engineering Geology
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• v.14 no.1
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• pp.47-60
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• 2004

The permeability coefficients were calculated by the homogenization analysis method with sufficient consideration of fracture geometry dependent on aperture change. According to the results of aperture measurements using a confocal laser scanning microscope, apertures on each measuring point display different magnitudes, indicating that fracture walls can not be assumed as parallel feature. After construction of fracture model based on the aperture values measured on each pressure level, the homogenization analysis was conducted to compute permeability coefficients. The calculated permeability coefficients distribute in the ranges of $10^{-1}~10^{-3}cm/sec$. Most of the specimens show decreasing permeability coefficients with the increase of the applied pressure. However, the decreasing rates of permeability coefficients do not show a constant trend on each pressure level. This phenomenon is well matched to the observation results of Chae et al. (2003). It proves that aperture change strongly influences on permeability characteristics. Three sections of each specimen have all different values of permeability coefficient. It suggests that the variation of permeability coefficient depends sensitively on aperture magnitudes and characteristics of fracture geometry. It is very important to consider accurate fracture geometries for analysis of permeability characteristics in rock fractures bearing different aperture distribution. Therefore, it needs to consider sufficiently the fracture geometries for calculating the permeability coefficients of fractures.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.3 no.1
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• pp.52-61
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• 2000

Permeability is important factor in the geotechnical problems, such as seepage discharge and dissipation of excess pore water pressure. The Kozeny-Carman equation works well for graded soils but serious discrepancies are found in clays. Major factor for these discrepancies is the tortuous flow path and unequal pore size. To estimate the permeability of fine grained soils, a permeability equation in which swelling potential is coupled with Kozeny-Carman equation is proposed in this study. To verify proposed equation, a series of variable head permeability test was carried out for steel making slag and sludge mixed with bentonite. The coefficients of permeability which is measured in the laboratory is compared with the values by the proposed equation. From the comparison, it is shown that the proposed equation can predict the coefficient of permeability of clays with satisfaction. As steel making slag and sludge is industry waste, it is reused as material of road foundation and cement but the rate of use is low. It mixed sodium-bentonite with high swelling property and permeability decrease effect. Then, Admixture investigates reuse possibility as liner of waste fill.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.2
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• pp.91-96
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• 2010

The purpose of this study is to find problems about pedestrian road of tourist resort and to make new type of sidewalk pavement with wood chip and binder using urethane resin on the parks and tourist resort. The wood chip pavement has new economics and durability with comfortable texture. Samples of these pavement materials were tested for tensile strength, permeability and ball rebound value. Also, after immersion for 24 hours, tensile strength, samples' thickness and weight were measured and discussed the strength reduction according to the water immersion. Tensile strength experimentation was examined on dry condition and water immersion. The result of examination on dry condition was 1.06MPa and on water immersion was 0.67MPa. The results showed 36.8% decreasing rate of tensile strength. Permeability experiment test based on field permeability method of pavement were conducted as a result, permeability coefficients were in the range of 0.67~0.78mm/s that all exceeds object permeability coefficient. Elasticity experiment was based on elasticity test method of Japan road association. GB coefficient was 21% and SB coefficient was 10%. GB coefficient and SB coefficient increased if fine aggregate were increased.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.362-369
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• 2005

Studying unsaturated soil mechanics, determination of soil water characteristic curve and permeability equation is an essential factor but it is not easy. In this research a new testing apparatus was developed to determine soil water characteristic curve and permeability equation. The testing to get saturated permeability coefficients and soil water characteristic curves for two soils was performed by using the developed testing apparatus. First, a saturated permeability testing was performed and then the testing to get soil water characteristic curve of a drying process was performed. Next, the testing to get soil water characteristic curve of a wetting process was performed. Testing results showed hysteresis phenomena between soil water characteristic curve of a drying process and soil water characteristic curve of a wetting process. The permeability equations were determined by a theoretical method where a saturated permeability coefficient and a soil water characteristic curve were used.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2010.05a
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• pp.87-88
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• 2010

A permeability of concrete is a very important factors evaluating durability. So, we are carrying out a lot of relational data bases and experiment regarding a permeability. In order to evaluate a permeability of concrete, we are proceeding study on the water penetration and diffusion in concrete by water pressure. Because a way to evaluate a permeability of concrete has a limit. We will present a good method of evaluating durability of concrete using the water penetration depth of concrete by water pressure. To carry this out, we executed experiment with penetration depth of concrete by water pressure and verified it though FEM analysis.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05a
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• pp.69-72
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• 2011

The purpose of this study is to identify basic property of porous concrete using cooper slag as fine aggregate. The specimens were made with cooper slag with various mixing ratio(10, 20, 30, 50%), porous concrete and porous concrete containing river fine aggregate and crushed fine aggregate, which W/B ratio fixed 0.25. Compressive strength, Flexural strength, coefficient of permeability. From the test results, various fine aggregate mixing ratio improves compressive strength and flexural strength, but cooper slag fine aggregate mixing ratio over 20%, concrete indicates trend to decrease performance of permeability. Concrete containing fine aggregate is improved the performance of permeability and strength compared to other specimen, when age 28days, and cooper slag mixing ratio less than 20% concrete indicates better performance than cooper slag mixing ratio 20% over.

• Journal of the Korean Geotechnical Society
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• v.15 no.4
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• pp.69-83
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• 1999

The permeability of converter slag, replacing material of sand mat on improving soft clay foundation, was evaluated in the laboratory. The effects of grain size, flow water time and aging were investigated using sea and fresh water. In the case of converter slag submerged with fresh water, the coefficients of permeability in A and B samples less than 10 mm grain sizes were measured as $6.52\times10^{-2}cm\; per\; sec\; and\; 5.99\times10^{-1}/cm$ per sec respectively, while they were $1.88\times10^{-2}/cm\; per\; sec,\; 3.86\times10^{-1}/cm$ per sec respectively under sea water condition. Also, the condition of turbulent flow may exit and was experimentally identified from the relationship between hydraulic gradient and seepage velocity. After 100 days under sea water condition, the coefficients of permeability of A and B samples decreased ten times than initial values. The reduction of permeability coefficient was considered to result from the filling of voids in high-calcium quicklime(CaO).

• Environmental Engineering Research
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• v.25 no.1
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• pp.96-103
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• 2020

The aim of this study is to investigate the effect of five different combinations including: sand 70%, bentonite 30% (S₇₀B₃₀)- sand 80%, bentonite 20% (S₈₀B₂₀)- sand 80%, organophilic 20% (S₈₀M₂₀)- sand 60%, bentonite 20%, organophilic 20% (S₆₀B₃₀M₂₀) and sand 75% - bentonite 15% - organophilic 10% (S₇₅B₁₅M₁₀) on landfill linear structure in order to decrease phenol leaching. Hydraulic conductivity and adsorption behavior of the samples were investigated. The results demonstrated that the lowest hydraulic conductivity coefficient ($1.16{\times}10^{-11}{\frac{m}{s}}$) was obtained for S₇₀B₃₀. Furthermore, adding more than 20% of bentonite had no significant effect on reducing permeability. Moreover, Freundlich isotherm was introduced as the best model explaining adsorption behaviour due to its highest determination coefficient (0.945). The best samples for adsorption capacity of phenol and for both permeability and adsorption are S₈₀M₂₀ and S₆₀B₃₀M₂₀, respectively. Although the presence of bentonite was effective in reducing hydraulic conductivity, organic clay had no considerable impact on reducing permeability. Though, it's an exceptional role in adsorbing organic contaminants including phenol cannot be ignored. To meet all regulatory constraints, the optimal compound is made up of 10.2% of bentonite and 2.8% of organophilic clays with a minimized cost of 13.64 ($/ton).