• Ecology and Resilient Infrastructure
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• v.7 no.1
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• pp.26-42
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• 2020

Soils are the basis for plant rooting and ecosystem creation, the site of life for humankind, and require much time for their creation, so there will be no disagreement about the importance and necessity of soil conservation and management. Soil resilience is the ability of soils to maintain their original structure and function (resistance and recovery) from various kinds of disturbances, and is an indispensable field of study that prepares for a future with high uncertainty and unpredictability. Therefore, this study summarizes the concept and necessity of soil resilience, which is not yet widely known in Korea, and the contents of previous studies were reviewed. This study was carried out with the aim of contributing to lowering the threshold for entry into resilience research for domestic and foreign researchers who are new to soil resilience. In the first part of this study, we introduced resilience and soil resilience, and in the second part, we summarized the main causes of stress or disturbance that have been studied by many soil resilience researches. This makes it easy to find the references authors need. It is virtually impossible to find the same soil environment because there is no same area on the earth with all the same rock, climate, human activity, and culture, suggesting that each soil has its own uniqueness. Therefore, the researcher who wants to utilize the results of this study should take into consideration the specificity of the soil and the region to which the soil resilience is introduced, and modify it if necessary. In addition, efforts should be made to strengthen the network of soil resilience researchers to create a basis for sharing and actively utilizing the research results.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.5
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• pp.98-108
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• 2009

The purpose of this study is to analyze the characteristics of limited methods, economics and breeding appropriateness of native and imported ground cover plants in the methodology of a shallow soil rooftop garden. The new shallow soil rooftop gardening method uses a total of 13cm in soil thickness, including 4.5cm of top soil on a 7.5cm rock-wool-mat stacked onto a 1cm roll-type-draining plate. The total construction cost for each method of soil level within the design price standard for SEDUM BLOCK is 89,433won/$m^2$, and for DAKU is 92,550won/$m^2$. By comparing those two methods, the construction cost of the shallow soil artificial foundation methodology is 45,000won/$m^2$; this shows the new method is 50% less expensive than the existing method of shallow soil rooftop gardening. The experiment was executed on the rooftop of the Korean National Housing Corporation to ensure validity of the shallow soil artificial foundation planting, and the sample plants which were imported and grown now in native covering. A list investigating the growing plants was made of the cover rate in each plant class, both while alive and the dry plant weight. The native ground cover plants, Sedum kamtschaticum, Sedum middendorffianum, Allium senescens, Sedum sarmentosum, Aquilegia buergariana, and Caryopteris incana increased the cover rate, live weight and dry weight in the shallow soil artificial foundation method. Among the imported cover plants, Sedum sprium and Sedum reflexum, the cover rate increased and growth conditions improved. However, some species needed weed maintenance. After examination with the less expensive shallow soil artificial foundation method and growth analysis, it was found that rooftop gardens are a low-cost option and the growth of plants is great. This result shows the new method can contribute to the proliferation of rooftop gardens in urban settings.

• Tunnel and Underground Space
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• v.19 no.6
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• pp.490-497
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• 2009

The horizontal and vertical response spectra using the observed ground motion from the recent 5 macro earthquakes were analysed and then were compared to both the seismic design response spectra(Reg Guide 1.60), applied to the domestic nuclear power plants, and the Korean Standard Design Response Spectrum for general structures and buildings(1997). 74 horizontal and 89 vertical observed ground motions, without considering soil types, were used for normalization with respect to the peak acceleration value of each ground motion. The results showed that the horizontal MPOSD(Mean Plus One Sigma Standard Deviation) response spectra revealed much higher values for the whole frequency bands above 1 Hz than Reg. Guide(1.60). For the vertical response spectra, the results showed slightly higher than just between 7 and 8 Hz frequency band. The results were also compared to the Korean Standard Response Spectrum for the 3 different soil types and showed that the horizontal MPOSD response spectra revealed much higher values for the whole periods below 2 second(0.5 Hz) than those of SE soil type. The vertical response spectra showed similar to the values of the Korean Standard Response Spectrum of SD soil type. These spectral values dependent on frequency could be related to characteristics of the domestic crustal attenuation and the effect of each site amplification. However, through the qualitative improvements and quantitative enhancement of the observed ground motions, the conservation of horizontal seismic design response spectrum should be considered more significantly for the whole frequency bands above the 1 Hz.

• Journal of Environmental Impact Assessment
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• v.16 no.2
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• pp.143-156
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• 2007

This study has researched the management status and the pollution level of water, soil, stream sediments of 11 abandoned coal mines out of a total of 12 within Obong-Dam area except Bukyung mine, which was submerged when constructing Obong-Dam, and selected areas which are in needs to have pollution control facilities in the first place. From the results of examination on the runoff at the waste rock pile and mineheads, the runoff from Sueun mine (pH, Fe, Al), Samwon mine (pH, Al), Wangdo mine (pH, Al), Mose mine (pH, Fe, Al) and Daeryeong mine (pH) exceeded the permissible discharge standards of the water quality, but the water at merging point with Obong-Dam after joined with Doma branch satisfied both Water Quality Standards and Drinking Water Quality Standards. In regard to groundwater contamination, it is found that areas where exceeded the Drinking Water Quality Standards are Wangdo mine (pH), Jangjae mine (pH, Zn), Daeryeong mine (pH) whereas all areas satisfied Soil Contamination Warning Standards of Soil Environmental Conservation Law. When comparing a research result on underwater sediments of branches of abandoned mines to the EPA Guidelines for classification of great lakes harbor sediments, Dongguk Gaerim (Fe), Jungwon mine (Fe), Daebo mine (Mn), Samwon mine (Mn) and Daeryeong mine (Mn) showed mid-level of contamination, whereas Sueun (Fe, Mn), Daebo mine (Fe), Woosung mine (Fe, Mn), Wangdo mine (Fe, Mn), Mose mine (Fe) and Daeryeong mine (Fe) showed high-level of contamination. In addition, contamination levels of underwater sediments in Wangsan and Doma branch where abandoned mine's branches merge together, Wangsan branch showed no contamination at all whereas Doma branch shows mid-level of contamination which reflect the Doma branch is affected by waste rock pile and minehead runoff of the abandoned mines in the Doma branch area. It is concluded that Mose mine and Sueun mine required treatment of acid mine drainage. and Wangdo, Jungwon, and Samwon mines were in need of mine tailing and erosion control work. The Samwon mine additionally required a control system for closed minehead runoff. Although the Samwon mine reached a high concentration of Al, Mn $Ca^{2+}$, $SO{_4}^{2-}$ in the runoff, the levels decreased after it was combined with a tributary. It has been concluded that after further monitoring of the cause of pollution, a preventive measure system may be needed to be built.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.3
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• pp.1778-1785
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• 2014

In order to construct offshore structures safely, geotechnical investigation should be carried out with high accuracy. Up to now, onshore geotechnical investigation equipments installed on the barge are used for offshore geotechnical investigation. In this case, many limitations can be confronted such as deep water depth, high wave, strong current, severe wind and so on. For the safe and economic offshore geotechnical investigation with high precision, a seabed type unmanned automated site investigation equipment is developed. It can be operated remotely underwater conditions with 100m water depth and can explore the ground depth of 50m. Also, the standard penetration test (SPT), soil boring, soil sampling and rock coring can be possible using the equipment. Numerical analysis was conducted to secure the stability of the equipment against current of 4 knot. Energy efficiency of SPT apparatus which is attached to the equipment shows 78% in average.

• Journal of Korean Society for Geospatial Information Science
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• v.19 no.1
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• pp.21-28
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• 2011

Site conditions affect the magnitude of loss due to geologic hazards including, but not limited to, earthquakes, landslides and liquefaction. Reliable geologic loss estimation system requires site information which can be achieved by GIS-based method using geologic or topographic maps. Slope data derived from DEM can be an effective indicator for classifying the site conditions. We studied and discussed the effect of different DEM resolutions in the site classification. We limited the study area to the south-eastern Korea and used two different resolutions of DEMs to observe discrepancies in the site classification results. Largest discrepancy is observed in the areal coverage of site class C(very dense soil and soft rock) and E(soft soil). Comparison of results shows that more areas are classified as site class B(general rock) or E(soft soil) when we use higher resolution DEM. The comparison also shows that more areas are classified as site class C or D(stiff soil) using lower resolution DEM. The comparison of results using resampled DEMs with different resolutions shows that the areal coverage of site class B and E decreases with decreasing resolutions. On the contrary, areal coverage of site class C and D increase with decreasing resolutions. Loss estimation system can take advantage of higher-resolution DEMs in the area of rugged or populated to obtain precise local site information.

• Economic and Environmental Geology
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• v.31 no.3
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• pp.215-222
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• 1998

The radon (Rn-222) potential of metropolitan subway stations and soils in Seoul city were delineated using alpha-track filter and EDA-200 radon detectors, respectively. The uranium (U) and thorium (Th) contents were also determined using a Multi Channel Analyzer to identify the sources of radon gas. The average U concentrations in Seoul varies according to basement rock types. For example, there is $9.40{\pm}10.11ppm$ in the Precambrian metasedimentary rock (PM), $9.08{\pm}2.85ppm$ in the Jurassic Kwanaksan granite (JK) and $4.94{\pm}1.43ppm$ in the Jurassic Seoul granite (JS). Uranium contents in soil samples are $10.30{\pm}4.74ppm$ in JK, $10.10{\pm}7.43ppm$ in PM and $6.69{\pm}3.95ppm$ in JS and these closely reflect the content of uraniferous minerals. The levels of soil radon are $604{\pm}273pCi/L$ in JK, $502{\pm}275$ in JS and $262{\pm}211pCi/L$ in PM. The soil radon concentrations are shown to reflect soil permeability and porosity rather than their U contents. The mean indoor radon contents in subway stations are $1.50{\pm}0.62pCi/L$ on the 4th line, $1.41{\pm}0.95pCi/L$ on the 3rd line, $0.84{\pm}0.13pCi/L$ on the 1st line and $0.80{\pm}0.25pCi/L$ on the 2nd line. The subway stations located in the JK have the highest average radon concentration with $2.04{\pm}0.65pCi/L$, where levels of $1.57{\pm}0.81pCi/L$ occur in the JS and $0.80{\pm}0.23pCi/L$ in the PM. The highest radon levels of 4.1 pCi/L occur mainly in Keongbokkung station on the 3rd line and these exceed 4 pCi/L of the US EPA action level.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.1
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• pp.1-9
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• 1991

A study was carried out to investigate the composition of rock-forming minerals and mineralogical characteristics of the five major parent rocks in Korea. The identification was done through the analyses of chemical. X-ray diffraction, thermal(DTA, TG), infrared spectroscopic, and microscopic methods. Among these methods, X-ray diffraction was considered to be the most rapid and effective way to identify minerals in the parent rocks. The main rock-forming minerals of the parent rocks were feldspars, quartz, and micas in granite and granite-gneiss, calcite and dolomite in limestone, quartz and calcite in shale, plagioclase and augite in basalt. A small amount of sesquioxides was identified as a accessory mineral by means of DTA from the parent rocks of Weoljeong series(granite) and Cheongsan series(granite-gneiss). The abrasion pH affecting the soil formation ranged from 7.5 to 8.4 in the parent rocks containing ferromagnesian minerals and carbonates. In the granite and granite-gneiss of which the main rock-forming minerals were feldspars and quartz with low content of biotite, the abrasion pH ranged from 6.2 to 6.4. In chemical composition of the parent rocks, Si, AI, and K oxides tented to increase with higher contents of quartz, feldspars, and muscovite, while Fe and Mg oxides with higher content of biotite, chlorite, amphiboles, and augite. Higher ignition loss in limestone and shale resulted in the release of $CO_2$ from calcite and/or dolomite.

• Journal of Korean Tunnelling and Underground Space Association
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• v.25 no.6
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• pp.583-603
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• 2023

Recently, the advancement of mechanical tunnel boring machine (TBM) technology and the characteristics of subsea railway tunnels subjected to hydrostatic pressure have led to the widespread application of shield TBM methods in the design and construction of subsea railway tunnels. Subsea railway tunnels are exposed in a constant pore water pressure and are influenced by the amplification of seismic waves during earthquake. In particular, seismic loads acting on subsea railway tunnels under various ground conditions such as soft ground, soft soil-rock composite ground, and fractured zones can cause significant changes in tunnel displacement and stress, thereby affecting tunnel safety. Additionally, the dynamic response of the ground and tunnel varies based on seismic load parameters such as frequency characteristics, seismic waveform, and peak acceleration, adding complexity to the behavior of the ground-tunnel structure system. In this study, a finite difference method is employed to model the entire ground-tunnel structure system, considering hydrostatic pressure, for the investigation of dynamic behavior of subsea railway tunnel during earthquake. Since the key factors influencing the dynamic behavior during seismic events are ground conditions and seismic waves, six analysis cases are established based on virtual ground conditions: Case-1 with weathered soil, Case-2 with hard rock, Case-3 with a composite ground of soil and hard rock in the tunnel longitudinal direction, Case-4 with the tunnel passing through a narrow fault zone, Case-5 with a composite ground of soft soil and hard rock in the tunnel longitudinal direction, and Case-6 with the tunnel passing through a wide fractured zone. As a result, horizontal displacements due to earthquakes tend to increase with an increase in ground stiffness, however, the displacements tend to be restrained due to the confining effects of the ground and the rigid shield segments. On the contrary, peak compressive stress of segment significantly increases with weaker ground stiffness and the effects of displacement restrain contribute the increase of peak compressive stress of segment.

• Korean Journal of Soil Science and Fertilizer
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• v.5 no.1
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• pp.17-23
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• 1972

The effect of completed mineral fertilizer on barley was investigated on ordinary upland and newly recrimed soil derived from granite, basalt and shale. 1. Yield of barley grains with application of completed meneral fertilizer 1 level varied from 100.8% to 233.1% on various soils in different parents rock, and 2 levels of the fertilizer varied from 250.1% to 309.5% on ordinary upland and newly recrimed soil derived from granite compared with control plot. But no effect on newly recrimed soil derived from basalt and shale. 2. $P_2O_5$, MgO and B contents in straw were increased, but Mn contents was decreased on all of soil. N contents in straw was decreased on the soil derived from granite, but $K_2O$ contents was increased on the soil derived from basalt and shale. 3. Relation between the yield and absorbed nutrient had related with positive correlection of 1-5%. 4. N and Mn contents in soil were decreased by application of completed mineral fertilizer, but soil pH, C.E.C. $Av-P_2O_5$, Ex-CaO, Ex-MgO and B contents were increased. Especially soil pH and C.E.C. were increased remarkably. 5. Relation between the yield and Ex-CaO and Ex-MgO contents in soil had related with positive correlation, but Mn contents had related with negative correlation.