• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1756-1767
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• 2008

Recently, a global trend has been established to facilitate the use of waste materials in geotechnical engineering applications. In Korea, where there is the need to save natural resources as these may become scare in the near future and to prevent excessive ground excavation for natural aggregates. The annual production of scrap tire and bottom ash has sharply increased in recent years. Therefore, it will be good waste resource recycling, if we can utilize the above wastes as fill materials in soft ground. In this study, based on the proven feasibility of bottom ash and tire shred-soil mixtures as lightweight fill materials, tire shred-bottom ash mixtures were suggested as a new lightweight fill material to replace the conventional construction material(soil) with bottom ash. Therefore, the main objective of this research is to investigate the feasibility of tire shred-bottom ash mixtures in order to estimate their suitability for the use of lightweight fill materials. So we carried out the performance tests of 2 large scale embankment which were made with tire shred-bottom ash mixture and the conventional fill material(weathered soil) respectively.

• Journal of Soil and Groundwater Environment
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• v.23 no.3
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• pp.43-50
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• 2018

In a previous study, the feasibility of four materials (bentonite, steelmaking slag, lime and organic compost) to induce soil aggregate formation was assessed and the mixtures of organic compost and lime were chosen as most effective amendments in terms of cost benefit. This work is a subsequent study to evaluate the effectiveness of those amendments in reducing soil loss in $15^{\circ}$ sloped agricultural area by using rainfall simulation test. Three different soils were treated with two conditions of organic compost/lime mixtures (2% + 2%, 3% + 1%, w/w). In the amended soils, soil fertility was increased due to the increase of CEC, T-N, and T-P. During the rainfall simulation, suspended solid in run-off water from amended soil were reduced by 43% ~ 78%. When the content of organic compost was higher than that of lime, reduction of soil loss was also increased by 67% ~ 78%. Sediment discharge was also decreased by 72% ~ 96% in the amended soil. Similar to the suspended solid analysis, higher organic compost content led to more reduction of soil discharging, which implies organic compost is more effective than lime in reducing soil loss. The overall result suggests that the mixtures of organic compost and lime could be used as amendment materials to reduce soil loss in sloped farmland.

• Journal of Soil and Groundwater Environment
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• v.18 no.1
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• pp.57-66
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• 2013

Although the quantity of dredged soils has increased owing to recent new harbor construction, sea course management, polluted sediment dredging, and four-river project, the reuse or recycling of those dredged soils has not done properly in Korea. To develop measures to utilize them in various ways for reuse or recycling, the biophysicochemical properties of dredged soils and sediment were assessed in this study. Samples were classified according to their sources-river and sea-by location, and as dredged soil and sediment depending on storage time. The results showed that dredged materials from the sea have high clay content and can be used for making bricks, tiles, and lightweight backfill materials, while dredged materials from the river have high sand content and can be used in sand aggregates. Separation procedures, depending on the intended application, should be carried out because all dredged materials are poorly sorted. All dredged soils and sediments have high salinity, and hence, salts should be removed before use for cultivation. Since dredged materials from the sea have adequate concentrations of nutrients, except phosphate, they can be used for creating and restoring coastal habitats without carrying out any additional removal processes. The high overall microbial activities in dredged materials from the river suggested that active degradation of organic matter, circulation of nutrients, and provision of nutrients may occur if these dredged materials are used for cultivation purpose.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.5
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• pp.356-361
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• 2014

The coal fly ash (CFA) may be utilized as an extender for organic waste composting at the same time fully expected to solve all industrial waste disposal and sawdust tribe. The main objective in this study was to evaluate the effect of CFA addition as a bulking agent for swine manure composting. To determine the suitable addition rate of CFA as a bulking agent, 0, 10, 20 and 30% of saw dust were mixed with 30, 20, 10 and 0% of coal fly ash, respectively. Compost quality for swine manure composting was to evaluate temperature, pH, C/N ratio, and phytotoxicity as germination index. Stability of compost increased with increasing levels of CFA as bulking agent during swine manure composting due to the high alkaline materials including CFA. C to N ratio in treatment added CFA was higher than that of the control without CFA. After finishing composting, germination index of lettuce and cabbage in swine manure compost added 10% of CFA was similar to the control, all the heavy metal contents were far below the stipulated standard for organic farming. These results indicated tahr coal fly ash as bulking agents might be alternative materials to save saw dust and apply industrial products for swine manure composting.

• Journal of Environmental Science International
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• v.22 no.7
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• pp.801-810
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• 2013

To improve the physical and chemical properties of the soil and increasing water-retaining property of the soil, Superabsorbent synthetic polymeric materials have been used. The experiment carried out from April to July 2012 after the influence evaluation of Superabsorbent synthetic polymeric materials to vines plant. The result shows that the study of Hedera japonica Tobler, the growth and the survival rates rank as media > hydroponic > superabsorbent synthetic polymers, and the growth and the survival rates are considerably pessimistic in the experiment of hydroponic and superabsorbent synthetic polymers. In the study of Trachelospermum asiaticum var. intermedium, the growth and the survival rates rank as hydroponic > media > superabsorbent synthetic polymers, the difference between the experiment of hydroponic and is very small and the survival rates are not very good in the experiment of superabsorbent synthetic polymers. In the study of Euonymus fortunei var. radicans Rehder,it is insignificantly difference among the different of planting based. Judging from these results, the differences are depending on the species of plants. The thesis holds that the characteristics of plant should be considered in plant cultivation and soil improvement in the future, and it is desirable to use the appropriate mixing ratio of soil in soil improvement as well.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.14 no.3
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• pp.245-251
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• 2016

Soil can be contaminated by radioactive materials due to nuclide leakage following unexpected situations during the decommissioning of a nuclear power plant. Soil decontamination is necessary if contaminated land is to be reused for housing or industry. The present study classifies various soil remediation technologies into biological, physics/chemical and thermal treatment and analyzes their principles and treatment materials. Among these methods, this study selects technologies and categorizes the economics, applicability and technical characteristics of each technology into three levels of high, medium and low by weighting the various factors. Based on this analysis, the most applicable soil decontamination technology was identified.

• Geomechanics and Engineering
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• v.16 no.5
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• pp.559-567
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• 2018

Technological innovations in sustainable materials for soil improvement have attracted considerable interest due to energy crisis and environmental concerns in recent years. This study presents results of a comprehensive investigation on utilization of nanocarbons in reinforcement of a residual soil mixed with 0, 10 and 20% bentonite. Effects of adding proportionate quantities (0, 0.05, 0.075, 0.1 and 0.2%) of carbon nanotubes and carbon nanofibers to soil samples of different plasticities were evaluated. The investigation revealed that the inclusion of nanocarbons into the soil samples significantly improved unconfined compressive strength, Young's modulus and indirect tensile strength. It was observed that carbon nanofibers showed better performance as compared to carbon nanotubes. The nanosized diameter and high aspect ratio of nanocarbons make it possible to distribute the reinforcing materials on a much smaller scale and bridge the inter-particles voids. As a result, a better 'soil-reinforcing material' interaction is achieved and desired properties of the soil are improved at nanolevel.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.1
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• pp.1-9
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• 2005

This study was conducted to establish a management plan for the Sangrim Woodlands restoration by analyzing the site characteristics of the Sangrim Woodlands Natural Monument(Natural Monument 154) in Hamyang-Gun, Gyoungsangnam-Do, Korea. Site preparation to enhance soil aeration should be applied because soil bulk density in all study sites was higher than soil compaction of natural forest soil area. Herbaceous plants could be introduced to hard soil strength for restoration of areas compacted by visitors. Also, visitors around forest areas should be restricted to enhance natural soil restoration. Soil pH in the Sangrim Woodlands was between 4.18 and 4.90. The values were lower than pH 5.34 of Korean forest soil originated from metamorphic parent materials. Lime fertilizer could be applied to reduce soil acidification in the woodlands. Short and long-term management plans such as periodical fertilizations to improve plant growth should be established to restore the Sangrim Woodlands which have high soil compaction, low soil pH and organic matter content.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.858-865
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• 2009

Based on the proven feasibility of bottom ash and tire shred-soil mixtures as lightweight fill materials, tire shred-bottom ash mixtures were suggested as a new lightweight fill material to replace the conventional construction material with bottom ash. Therefore, we carried out the laboratory test, field compaction test and performance test of large scale embankment in order to evaluate their suitability for the use of lightweight fill materials in the before studies. We could verified that the ash, tire-shred and the mixture are able to be the useful materials as light fill materials. In this study, we estimated the long-term compressible settlements for 6 materials such as TA(Tire-Bottom Ash mixture), TBA(Tire-Bottom Ash<5mm) mixture, TWS(Tire-Weathered Soil mixture), Bottom Ash, Bottom Ash(<5mm), Weathered soils.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.1
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• pp.55-62
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• 2003

Leachate generated from landfill material flows through soil gravitationally downward and. continues to flow until it encounters groundwater, posing the thread of pollution. So selection of liner material having a low permeability and testing method are required. The study was performed to find bentonite content of soil-bentonite mixtures for using as liner and cover of waste landfills. This paper includes results of consolidation tests and permeability tests and evaluates suitability and properties of soil-bentonite mixtures as impervious materials.