• Journal of Soil and Groundwater Environment
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• v.7 no.1
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• pp.41-51
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• 2002

Recently, domestic waste landfills are constructed sometimes on seashore area to provide large landfill area. In order to strengthen the foundation of landfills and to prevent the infiltration of leachate through the bottom, many cases of constructing cement hardened liners on seashore clays are found. In these cases, it is possible to have cracks in the hardened liners due to settlement with waste load since the stiffness of the hardened liner Is greater than that of clay liners. In this study, the capability of Self-Sealing and Self-Healing (SSSH) liner made with a seashore clay in the metropolitan landfill to prevent the percolation of water and leachate is examined using flexible-wall permeameter test and using uniaxial compression test. Applicability of SSSH to weathered granitic soil is also examined for self-sealing capabilities. The result of Flexible permeameter test for SSSH with the seashore clay showed that permeability obtained was lower than permeability criteria of Korean waste management law. The permeability and strength characteristics of SSSH with granitic soil and bentonite showed better results than with the seashore clay.

• Geotechnical Engineering
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• v.13 no.2
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• pp.9-16
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• 1997

Cut-off methods of controlling leachate migration from waste landfills and contaminated sites are studied. Permeability and chemical compatibility tests are prrforlned on slurry wall materials including soil-bentonite, cement-bentonite, cement / fly ash-bentonite, plastic concrete. Hydraulic conductivity of soil-bentonite mixture is the lowest of these four bacuill materials. The leachate from municipal solid waste has little influence on the permeability of the backfill materials. The bentonite slurry becomes flocculated and aggregated when exposed to the leachate. The results of the permeability test showed that the hydraulic conductivities of the backfill materials are in the order soil-beiltonite, Plastic concrete, cement-bentonite. And the result c: the compatibility test showed increase in permeability due to the effects of leachate. Thus, in designing the slurry wall it is essential to check the behaviour of the bentonite slurry and backfill materials on the compatibility with the contaminants.

• Journal of Korea Water Resources Association
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• v.33 no.1
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• pp.133-142
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• 2000

Series of tests were carried out to study permeability characteristics of unsaturated soils. The weathered soils taken from Inju, Sungwhan, and Kuri, were selected to have different amount of fine grained soils in order to find a possible correlation between the unsaturated permeability behavior and fine grained soils contents. Measurements of permeability for unsaturated soils were performed with a newly developed apparatus, which modeled after Klute's apparatus(1965a). The apparatus was designed to measure volumetric water content and permeability by applying incremental suction pressure. Permeability and volumetric water content of unsaturated soils generally decreased as density of the soil increased. The relationship between volumetric water content and permeability was not related to the fine grained soils contents because the plots scattered widely. By comparing volumetric water content with permeability, empirical parameters A and B could be determined, which made to be possible to predict unsaturated permeability from soil-moisture characteristics.

• The Research Journal of the Costume Culture
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• v.15 no.2 s.67
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• pp.276-283
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• 2007

The purpose of this study were to investigate characteristic changes on nonwoven fabric for disposable work clothes by the yellow soil printing. It separate grind yellow soil as two different size of particles $45\sim52{\mu}m$ and $53\sim65{\mu}m$ for hand screen printing on three kind of nonwoven fabrics. To examine the effect of yellow soil printing on nonwoven fabric were to observe, dyeability by using spectrophotometer, moisture regain by oven method, air permeability, anion property and antibacterial activity. The results were as follows: When yellow soil concentration increased from 5 to 10%, K/S value also increased from 1.05 to 1.88. When yellow soil concentration increased, moisture regain also increased. In same concentration, moisture regain occurred higher as particle of small size. Air permeability decreased when the charcoal printing concentration increased. Anion occurrence appeared $140\sim160ion/cc$ from three different kinds of nonwoven fabrics in 3% and 9% yellow soil concentration. Therefore, occurred anion ineffectively. In concentration of 3%, rate of deodorization measured as 89%, 83% and 87%, and 9% concentration caused 96%, 86% and 93% of high deodorization. Antibacterial activity examination in nonfinished nonwoven fabric resulted range of 60%, however, 3% and 9% concentration finished nonwoven fabric resulted 99.9% of excellent antibacterial activity Surface temperature increased $1.5\sim2^{\circ}C$ by yellow soil finishing.

• Journal of the Korean Geotechnical Society
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• v.28 no.11
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• pp.69-78
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• 2012

Conventional numerical analysis for rainfall-induced slope stability has been estimated by separating seepage and stress-strain behavior, respectively. Many researchers' models from commercial softwares and literatures define that partially saturated permeability is the only function of degree of saturation (or matrix suction) and then they do not consider hydraulic-mechanical characteristics for the analysis. However, in practice, the water flow processes in a deformable soil are influenced by soil skeleton movement and the pore water pressure changed due to seepage will lead to changes in stress and to deformation of a soil. The relationship between seepage and soil behavior causes a change of partially saturated permeability as well as saturated permeability with the lapse of time. Instability of partially saturated soil slopes due to infiltration would be analyzed from reduction of negative pore water pressure calculating the process of water flow based on predicted partially saturated permeability. Therefore, partially saturated permeability should be defined by the function of degree of saturation (or matric suction) and porosity. The paper presents the comparison between staggered and monolithic coupled analysis regarding seepage and stress deformation problems. As a result, the decrease in matric suction on soil slope from monolithic analysis is slower than that from staggered analysis.

• Geomechanics and Engineering
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• v.8 no.5
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• pp.649-661
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• 2015

This research provides insight on the laboratory investigation of the engineering properties of a lateritic soil modified with the mucilage of Opuntia ficus-indica cladodes (MOFIC), which has a history of being used as an earthen plaster. The soil is classified, according to AASHTO classification system, as A-2-6(1). The Atterberg limits, compaction, permeability, California bearing ratio (CBR) and unconfined compressive strength of the soil were determined for each of 0, 4, 8 and 12% addition of the MOFIC, by dry weight of the soil. The plasticity index, optimum moisture content, swell potential, unconfined compressive strength and permeability decreased while the soaked and unsoaked CBR increased, with increasing MOFIC contents. The engineering properties of the natural soil, which only satisfies standard requirements for use as subgrade material, became improved by the application of MOFIC such that it meets the standard requirements for use as sub-base material for road construction. The effects of MOFIC on the engineering properties of the soil resulted from bioclogging and biocementation processes. MOFIC is recommended for use as a modifier of the engineering properties of soils, especially those with similar characteristics to that of the soil used in this study, to be used as a pavement layer material. It is more economical and environment-friendly than conventional soil stabilizers or modifiers.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.994-1002
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• 1993

Soil deep loosening technique can improve the soil structure and increase the air permeability and water permeability of soil. It can increase the yield of crops in a large scale, particularly the plants with deep root system. This paper introduced the study on the deep loosening technique of sugarcance in Jinpen Farm where the soil is heavy caly with high ground water table. The implement and method of deep loosing, the experiments and results are include in this paper. The experimental results showed that the yield of sugarcane increased more than 20% after deep loosing.

• Journal of the Korean Society for Railway
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• v.3 no.3
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• pp.101-108
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• 2000

In this study, we tested hybrid pilot system combined with soil vapor extraction and bioventing methods on the contaminated railroad soil. So, we found out the remediability and operating conditions. Air permeability(k) and gas phase(O$_2$/CO$_2$/VOCs) level trend are very important to determine the remediation rate of the contaminated sites. Throughout hybrid pilot test on different conditions, the range of air permeability(k) was 1985∼1194 darcy. The tests results in hybrid system was appropriate on this test sites, and the suitable injection air flow rate was 3.5㎥/hr. So, we suggested a basic data for the remediation and management of contaminated railroad soil.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.1C
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• pp.7-16
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• 2012

In this paper, using the principle of Static Measurement Methods suggested by Huang (1998), a new experimental device has been made and used in order to calculate the unsaturated permeability of Nak-dong river sand with silt which is an important basic property in the unsaturated soil. This device was designed to measure changes of the unsaturated permeability according to the increase of matric suction. The value of the unsaturated permeability obtained in testing and that obtained using the empirical permeability functional formula were compared and analyzed. As a result, the value of the unsaturated permeability tends to be decreased according to the increase of relative density, silt content and matric suction. This tendency shows it is very closely related to the change of moisture content and void ratio. The empirical permeability functional formula presented by Frelund & Xing (1995) was regarded as the most appropriate model to represent the unsaturated permeability of Nak-dong River silty sand.

• Journal of the Korean Geotechnical Society
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• v.29 no.3
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• pp.61-70
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• 2013

Evaluation of permeability and coefficient of consolidation of clayey sand is critical in analyzing ground stability or environmental problems such as prediction of pollutant transport in groundwater. In this study, permeability tests using a flexible wall permeameter are performed to derive the coefficient of consolidation and permeability of reconstituted soil samples with various mixing ratios of kaolin clays and two different types of sands, which are Jumunjin and Ottawa sands. The test results indicate that the coefficient of consolidation and permeability plots linearly against clay contents in semi-log scale graphs for low clay mixing ratios ranging between 10 to 30%. It is also demonstrated that coefficient of consolidation and permeability of sand and clay mixture are dependent on the soil structure. Contrary to previous findings, the permeability is shown to be independent of the void ratio at low mixing ratios, which can be classified as non-floating fabric. The permeability decreases with the void ratio for floating fabric.