• Journal of the Korean Society of Industry Convergence
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• v.1 no.1
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• pp.51-58
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• 1998

This study was carried out to investigate the leaching characteristics by the landfill of solidified sludge. pH of leachate was 3.7 - 5.8 and 8.0 - 10.4 in each column using sand as a top-soil layer on filled municipal waste and solidified cake. $NH_3$-N in leachate was increasing in the each column using sand as a top-soil layer on filled dewatered sludge and solidified cake, but decreasing in the each column using sand and solidified cake by top-soil layer on filled municipal waste. Also the concentration of $NO_3$-N was on the way of stabilizing but was difficult to find any tendency until now. Zn and Mn in leachates were the highest in the column filled with the solidified sludge, Cr, Pb and Cd were low concentration at each column.

• Geomechanics and Engineering
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• v.29 no.1
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• pp.13-23
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• 2022

Peat soil has the characteristics of high moisture content, large void ratio and low shear strength. In this study, unconfined compressive strength and SEM tests are conducted to investigate the effects of ultrahigh moisture content, cement content, organic content and pH value on the strength of solidified peat. As an increase in the cement content and curing period, the failure mode of solidified peat soil changes from ductile failure to brittle failure. The influence of moisture content on the strength of solidified peat is greater than the cement content. As cement content increases from 10% to 30%, strength of solidified peat at a curing age of 28 days increases by 161%~485%. By increasing water content by 100%, decreases of solidified peat at a curing age of 28 days is 42%~79%. Compared with the strength of solidified peat with a pH value of 5.5, the strength of peat with a pH value of 3.5 reduces by 10% ~ 46%, while the strength of peat with a pH value of 7.0 increases by 8% ~ 38%. It is recommended to use filler materials for stabilizing peat soil with moisture content greater than 200%. Because of small size of clay particles, clay added in the cement solidified peat can improve much higher strength that that of sand.

• Journal of the Korean Geosynthetics Society
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• v.11 no.3
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• pp.37-42
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• 2012

The cement paste is mostly used as the filling materials of bored pile in Korea. The use of filling material based on cement paste is inefficient at field construction because it needs a lot of the charging mass. In addition, it has environmental problem according to the large amount of cement use because its strength is also larger than criterion. The excavated soil with stabilizer can be used as the filling materials when the bored pile is constructed. Therefore, this paper describes field application of solidified soil for economical efficiency and environment-friendly. The injection capacity of solidified soil is compared with cement paste's based on unconfined compressive strength test and field load test, and the appropriate of test results is evaluated by design criterion. The evaluation result shows that the capacity of excavated soil with stabilizer is similar to cement paste and the solidified soil is able to apply as filling materials of bored pile because it is satisfied with design criterion.

• Journal of the Korean GEO-environmental Society
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• v.15 no.10
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• pp.29-34
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• 2014

In order to examine strength properties depended on climate changes of solidified soil amended by porosity silica which enhance harms of cement, this study conducts a wetting and drying repetition test and then, attempts to verify strength properties before and after solidified soil gets environmental influence. Test pieces for the unconfined compression test changed the mixing ratio of solidified soil compared to mixed soil weigh to 5 %, 10 % and 15 %. For each step, it was created by mixing 0.5 %, 1.0 % and 1.5 % of wood chips, and curing period for 7, 14, and 28 days. Then, the wetting and drying repetition process was repeated 0, 3, 6, and 12 cycles to analyze mechanical properties. To also evaluate changes of relative dynamic elastic modulus before and after the wetting and drying, dynamic elastic modulus tests were conducted when each cycle was completed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.3
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• pp.238-247
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• 2012

To determine the possibility of solidified se wage sludge for use as a soil cover material in reclaimed land, the growth of energy crops and soil chemical properties investigated in each experimental plots during 2 years (2010 and 2011). The experimental plots consisted of the mixing with solidified sewage sludge plot (SS50), the covering with solidified sewage sludge plot (SS100), and the original reclaimed land plot (ORL) on reclaimed land for the intended landfill in Sudokwon Landfill Site Management Corporation (SLC). Plant height, measured in the second year (2011), was highest in the Geodae 1 grown at plots treated with solidified sewage sludge. The growth of energy crops cultivated in both SS50 and SS100 were better than in ORL. The contents of organic matter (OM) and total nitrogen (T-N) at both SS50 and SS100 were considerably higher than that of the ORL over 2 years. However, the soil from ORL showed higher salinity with high contents of exchangeable $Na^+$ cation than that of SS50 and SS100 over 2 years. We consider that soil chemical and physical properties on reclaimed land used in this study could be improved by the application of solidified sewage sludge due to following reasons. Firstly, the application of solidified sewage sludge may provide soil nutrients on reclaimed land i.e. the growth of energy crops better than in ORL, resulted in more OM and T-N contents in SS50 and SS100. Secondly, the top layers mixed or covered with solidified sewage sludge on reclaimed land may be prevented the salinity accumulation due to capillary rise to surface soil, and improved the cultivation layer for effectively propagating the rhizomes of energy crops. Thus the solidified sewage sludge may be a great soil cover materials for cultivation of bioenergy crops in reclaimed land.

• International Journal of Highway Engineering
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• v.8 no.1 s.27
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• pp.45-54
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• 2006

The Construction policy of government ever since 1970s have brought the economical growth, but has been causing environmental problems. Most roads were paved either asphalt concrete or portland cement concrete. These types of pavements has caused to rise temperature by making local heat islands in urban during summer time. Recently the wet-mixing solidified soil pavement, a kind of soil-cement, has developed and has been applied to the environment-oriented pavement. The solidified soil wet-mixed is placed on the subgrade along with asphalt concrete and portland cement concrete. Thermistors are laid in these field test pavements. The temperature gradients of these pavements are automatically measured with time. As the results of this test, the equation estimating surface temperature of pavement is proposed by analyzing measured temperature data. It is shown that the temperature change within the surface layer due to the change of air temperature is the greatest in the asphalt mixture and the least in the solidified soil mixture. Since it is proven that this wet-mixing solidified soil pavement emit less radiant heat than other existed pavements. Therefore this type of pavement can be successfully applied to the roads, such as walks, parkways, and bikeways, which are required to be human-friendly and environment-oriented.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.739-742
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• 2002

Immobilization of contaminants in contaminated soils by solidification processes is an attractive potential remediation process. In this study, the treatability of lead, copper, toluene, and COD was investigated by leaching test. Industrial sand was adopted as the test material and was contaminated with lead copper, and toluene to 100mg/kg, 500mg/kg, 200mg/kg respectively. P solidifying agent was used as the binder(20% by weight of contaminated soil) in the solidification treatment. The leachability of contaminants leached from the solidified soil was evaluated using column test. The percentage of contaminants leached from the solidified soil was significantly reduced by reaction of waste species with cement components and encapsulation reaction of binder. Based on the tests, it is ascertained solidification process can be a very effective method to control the elution of contaminants from the contaminated soil.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.593-596
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• 2003

The special amendment agent used in this study is mainly composed of inorganic metal salts such as sodium chloride, magnesium chloride, potassium chloride, calcium chloride, thus is friendly to the environment, and has a function of soil-cement-agent solidification. In this study, a series of laboratory and field experiments including unconfined compressive strength, permeability, pH test, constituent analysis, leaching test were carried out to analyse engineering and environmental characteristics of solidified sludge. The results of this research showed that the solidified sludge could be efficiently used in covering, filling, and planting materials.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.8
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• pp.768-774
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• 2008

To evaluate the effect of the solidified/stabilized sewage sludge on landfill sites, lysimeter tests were conducted. Lysimeters (LR1, LR2, and LR3) were filled with the material(Compost : Fodder : Sand = 10 : 10 : 80) and covered with different types of the cover soils, the G solidified sludge produced from the neutral solidifying chemical agent(LR1), the A solidified sludge produced from the alkali solidifying chemical agent(LR2), and the weathered granite soil(LR3). Those lysimeters were kept at the temperature controlled room with 30 $\pm$ 2$^{\circ}C$ for about 450 days. As the results, it was appeared LR2 > LR1 > LR3 that total gas production rate(L), gas production rate(L/VS(kg)) and cumulative gas(CO$_2$ + CH$_4$) production. There were not significant differences at decrease of the COD$_{Cr}$ in the leachate from LR1 and LR3. Thus, it had been shown that the use of the G solidified sludge as cover soil did not affect the COD$_{Cr}$ in the leachate. The COD$_{Cr}$ from LR2 had been increased since around 250 days because solidified/stabilized sewage sludge became re-slurry. T-N and T-P from LR3 also were higher than LR1 and LR2. Also were, the use of the solidified/stabilized sewage sludge as a cover soil, therefore, did not affect the T-N and T-Pconcentrations in the leachate.

• Journal of Environmental Health Sciences
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• v.30 no.5 s.81
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• pp.388-394
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• 2004

Seaweed waste(SWW) was used to improve the liner effect in recycling of dredged soil as the landfill liner. It was found that the compressive strength became somewhat lower when SWW was added than that was when Ordinary Port-land Cement(OPC) only was added. The permeability coefficient, however, became lower in this case which showed the lowest permeability coefficient when the addition of SWW was one percent. Hence, to comply with the regulations for the compression strength and permeability coefficient of landfill liner, the addition of OPC should be over eight percent and that of seaweed waste one percent. The results of leaching test showed that the solidified material was not against the laws of waste control, so it is possible to use as the landfill liner and to expect sufficient economic effects because wastes such as dredged soil and seaweed can be recycled.