• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.561-566
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• 2009

Alluvium is sedimentary stratum and composed of gravel, sand, silt, clay. Permeability of alluvium is the higher. If alluvium have lots of aquifer, will be of great use heat source and heat sink of heat pump. Alluvium aquifer contain the thermal energy of surrounding ground. Also geothermal heat pump using alluvium aquifer reduce expenses than general geothermal heat pump, because geothermal heat pump using alluvium aquifer make use of single well. In this study geothermal heat pump using alluvium aquifer was installed and tested for a building. The heat pump capacity is 30USRT. Temperature of ground water is in $12{\sim}17^{\circ}C$ annually and the quality of the water is as good as living water. The heat pump cooling COP is 4.4 ~ 4.7. The system cooling COP is 3.25 ~ 3.6. This performance is as good as BHE type ground source heat pump.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2003.04a
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• pp.513-516
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• 2003

This study was performed in two ways, which are 'Before' 'After' carrying out trench search through GPR which is called 'Non Destructive Geophysical' to the expected area where the remains of historic interest could be distributed within the construction site from Dae-gu to Busan. As a result, the layer containing gravel and sand has more irregular specular surface then others containing silt and clay. And, this paper, irregular specular surfaces of prominence and depression patter appeared. After performing trench search, verified that the site yield dolmens and lots of stone implements.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.43-44
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• 2016

Large amount of dredged sea soil is produced in southeast seashore region in during harbor maintenance. Disposal of dredged sea soil has become difficult due to the environmental regulation. Therefore, disposal of dredged sea soil method is to landfill. But, the capacity of the landfill limit state and if the size of the dredged sea soil is in the range of silt or clay, it cannot be used as reclamation material because ground subsidence occur. In this study, analyzed the pozzolanic activity of dredged sea soil. Analysis of the results showed a pozzolanic activity of dredged sea soil. In addition, incorporation of heat treated dredged sea soil increase both 28 and 56 day compressive strength of mortar specimen.

• Journal of the Korean GEO-environmental Society
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• v.14 no.1
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• pp.33-42
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• 2013

In this paper, a series of monotonic undrained shear tests were carried out on four kinds of sand-fine mixtures with various fines content. Two kinds of sands (Silica sand V3, V6) and fines (Iwakuni natural clay, Tottori silt) were mixed together in various proportions, while paying attention to the void ratio expressed in terms of sand structure $(F_c{\leq}F_{cth})$. The undrained shear strength of mixtures below the threshold fines content was observed so that as the plastic fines content increases, maximum deviator stress ratio decrease for dense samples while an increase is noted for loose samples. For non-plastic fines, the increase in the amount of fines leads to an increase in density of the soil, which results in an increase in strength. Then, the monotonic shear strength of the mixtures was estimated using the concept of granular void ratio. It was found that the shear strength of mixtures is greatly dependent on the skeleton structure of sand particles.

• The Korean Journal of Ecology
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• v.14 no.1
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• pp.113-117
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• 1991

Comparisons of the physico-chemical properties of earthworm(Lumbricus terrestris) soil casts and top soil of red pine forests in a limestone area were carried out. The casts production durign August and September in 1990 amounted to 6∼7t/ha. The particle of top soil and casts ranged 40∼50% and 10∼20% for sand , 25∼30% and 30∼35% for silt, and 20∼25% and 55∼65% clay, respectively. Significant difference in pH value was not observed between casts and top soil. The casts had 1.4times of organic matter, 1.5times of N, 1.8times of available P, 2times of exchangeable K, 1.3times of exchangeable Ca, and 1.6times of exchangeable Mg than the top 10cm of soil did. Earthworms have altered the soil texture and increased nutrient availability through production of the soil casts in this limestone area.

• Asian Journal of Turfgrass Science
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• v.8 no.3
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• pp.149-165
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• 1994

This report was investigated on the soil and mineral nutrient erosions in comparison among the vegetation floors of M isranthus sisensis, Arternisia stelleriana, Rhododendron mucronula turn, Zoysia ja-ponira and Pinus deusitlora communities and the naked soil on Mt. Keum-hak in Cheolwon-Koon, The erosion of clay, silt, fine sand and coarse sand of the surface soils under the Z. japonira grass-land was far less then those of M. sinensis, A. stelleriana, R. murronulatum and P. densiflora com-munities and the naked soil, The loss of mineral nutrients due to the soil erosion was the lowest level in the Z. japonira grassland and the highest level in the P. densiflora forest and the naked soil, respectively.

• Journal of Korean Society for Geospatial Information Science
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• v.11 no.1 s.24
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• pp.45-49
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• 2003

This study was peformed in two ways, which are 'Before' 'After' carrying out trench search through GPR which is called 'Non Destructive Geophysical' to the expected area where the remains of historic interest could be distributed within the highway construction site from Dae-gu to Busan. As a result, the layer containing gravel and sand has more irregular specular surface then others containing silt and clay, And, apart block irregular specular surfaces of prominence and depression patter appeared. After performing trench search, verified that the site yield dolmens and lots of stone implements.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1109-1114
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• 2008

To investigate the effect of sample size on coefficient of consolidation of non-homogeneous soil, the result of a large size consolidation test using a huge undisturbed sample with $1200mm(D){\times}2000mm(H)$ in dimension is compared with that of oedometer test using undisturbed small sample. In addition, test results are compared with those of same test using remold sample. Experimental results show that, due to the lump of sand/silt was mixed in sample, the coefficient of consolidation of undisturbed samples have a difference for each tests. Whereas, the difference of coefficient of consolidation between remolded large and small samples is not found. Because sample size affects the test results, sample must be carefully selected for non-homogeneous soil.

• Journal of the Korean Geophysical Society
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• v.6 no.4
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• pp.245-259
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• 2003

Two multichannel analysis of surface wave (MASW) surveys were conducted over a soil site in Tacoma Water's Green River Facility, Washington, where construction of a chemical treatment facility had been planned. The purpose of the surveys was to compare soil stiffness characterized by shear-velocity (Vs) distribution before and after Deep Dynamic Compaction (DDC) operation that was designed to improve the soil stiffness. Site soil consisted of very heterogeneous gravel and cobbles in a sand-and-silt matrix. Results from each survey are represented by two 2-D Vs maps delineating Vs variation of soil below the surveyed lines. One map was constructed from those dispersion curves that were analyzed with a significant amount of subjective judgment involved, whereas the other map was constructed from those dispersion curves analyzed with as much objective information as possible. Comparison of 2-D Vs maps indicates that Vs actually decreased after the DDC operations, possibly due to the loss (or reduction) of cohesive bonding between soil particles caused by the compaction operations.

• Journal of the Korean Geophysical Society
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• v.6 no.4
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• pp.269-276
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• 2003

Sub-bottom profile were conducted in Chungju Regulation Lake by use of ground penetrating radar(GPR). The survey area covers approximately 1,000,000 $m^2$ and total survey line length is about 5km and more. GPR surveys with GPS system were made across and transverse direction of the lake. From the survey results of GPR, it could be possible to distinguish the gravel and/or sand dominant bed from silt and/or clay material dominant bed.