• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.658-666
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• 2020

The purpose of this study was to select a suitable planting substrate for multilayered plantings in an apartment landscape space. The experiment was conducted between May to October 2019, at the National Institute of Horticultural and Herbal Science. Planting substrate was prepared in six repetitions of eight treatment zones using mulching material, horticultural soil, bottom ash, and subgrade soil. Rosa hybrid 'Barkarole' and Hydrangea macrophylla 'Nikko Blue' were selected as the experimental plants. We investigated the monthly variation and effect of the substrate type on the growth (plant height, number of branches, leaf length, leaf width, and plant area of the substrates) of the plants. In R. hybrid 'Barkarole' grown in 20 cm of horticultural soil and 10 cm of bottom ash, the plants were taller(102.2±5.8 cm), had more branches (5.5±0.6 each), longer leaves (10.9±1.0 cm), and greater leaf width (6.2±0.5 cm) and plant area (4077.1±416.6 cm²)(p<0.05). H. macrophylla 'Nikko Blue' showed the best growth from 3cm of mulching, 20cm of horticultural topsoil, and 10cm of bottom ash, which resulted in taller plants (43.6±2.1 cm), more branches (4.9±0.8 each), longer leaves (7.2±0.5 cm), and greater leaf width(4.3±0.3 cm) and plant area (344.5±43.2 cm²). Through this study, it was possible to propose an optimal planting substrate for shrubs for multi-layered landscaping.

• Journal of the Korea Concrete Institute
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• v.16 no.6 s.84
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• pp.751-757
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• 2004

Artificial lightweight aggregates and solids were manufactured with coal ash(fly ash, bottom ash). In order to apply alkali-activated coal ash(fly ash, bottom ash) artificial lightweight aggregate to concrete, several experimental studies were performed. Thus, it can be noticed the optimal mix proportion, basic characteristies, mechanical properties and environmental safety of alkali-activated coal ash(fly ash, bottom ash) solid and alkali-activated coal ash(fly ash, bottom ash) artificial lightweight aggregate. Also, the freezing-thawing test property of concrete using the alkali-activated coal ash(fly ash, bottom ash) artificial lightweight aggregate was investigated. As a result, the optimal mixing proportion of coal ash(fly ash, bottom ash) solid to make alkali-activated artificial lightweight aggregates was cement $10\%$, water glass $15\%$, NaOH $10\%$, $MnO_2\;5\%$. Alkali-activated coal ash(fly ash, bottom ash) solid can achieve compressive strength of 36.4 MPa, at 7-days, after the paste was cured at air curing after moist curing during 24 hours in $50^{\circ}C$. Alkali-activated coal ash(fly ash, bottom ash) artificial lightweight aggregate that do impregnation to polymer was improved $10\%$ crushing strength $150\%$, and was available to concrete.

• Korean Journal of Materials Research
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• v.22 no.2
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• pp.71-77
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• 2012

When a new bonding agent using coal ash is utilized as a substitute for cement, it has the advantages of offering a reduction in the generation of carbon dioxide and securing the initial mechanical strength such that the agent has attracted strong interest from recycling and eco-friendly construction industries. This study aims to establish the production conditions of new hardening materials using clean bottom ash and an alkali activation process to evaluate the characteristics of newly manufactured hardening materials. The alkali activator for the compression process uses a NaOH solution. This study concentrated on strength development according to the concentration of the NaOH solution, the curing temperature, and the curing time. The highest compressive strength of a compressed body appeared at 61.24MPa after curing at $60^{\circ}C$ for 28 days. This result indicates that a higher curing temperature is required to obtain a higher strength body. Also, the degree of geopolymerization was examined using a scanning electron microscope, revealing a micro-structure consisting of a glass-like matrix and crystalized grains. The microstructures generated from the activation reaction of sodium hydroxide were widely distributed in terms of the factors that exercise an effect on the compressive strength of the geopolymer hardening bodies. The Si/Al ratio of the geopolymer having the maximum strength was about 2.41.

• Resources Recycling
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• v.16 no.2 s.76
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• pp.40-47
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• 2007

This paper described recycling of the bottom ash, sourced from the local incinerators as a fine sand for concrete. 10% bottom ash was substituted for the ordinary beach sand in the mortar(on a weigh basis), in conjunction with the pozzolznic diatomite. The specimens were tested according to KS L 5105 and analysed by TCLP(Toxic Chemical Leaching Procedure). The results showed that the hazardous heavy metals in the bottom ash are within the maximum permissible limit of TCLP. The compressive strength of the mortar with 10% bottom ash was highly improved, compared to the control mortar when the pozzolanic diatomite was used. It revealed that the hazardous heavy metals of the mortar with 10% bottom ash were leached within the maximum permissible limit of TCLP. It was concluded that the bottom ash can be reused as a fine sand for concrete when the pozzolanic diatomite was used as a stabilizer.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.381-384
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• 2008

The artificial lightweight aggregate was manufactured using stone-dust(SD) and bottom ash(BA) from crushed aggregate manufacture process and thermoelectric power plant respectively. The properties of artificial lightweight aggregate according to mixing ratio of SD and BA was that the density was decreased and the absorption was increased with increasing BA content, because bottom ash was contained many unburned carbon and $Fe_2O_3$ which generates gas by oxidation during a sintering process. The appropriate mixing ratio of SD and BA was estimated at about 5:5. The properties of artificial lightweight aggregate according to addition flux admixture was that it had lower density with increasing of $Na_2SO_4$ content. In this study, we could developed the artificial lightweight aggregate as the bulk density was $1.52g/cm^3$ and water absorption 7.3% under the condition that mixing ratio of SD:BA was 5:5, $Na_2SO_4$, $Fe_2O_3$ 1%, sintering temperature $1,150^{\circ}C$ and sintering time 15mins.

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.1
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• pp.99-109
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• 2015

In the construction industry, the interest for recycling aggregates is rising as more people demand for alternatives due to lack of supply of natural aggregates and environmental problems. However, in order for recycled aggregates to be used in infrastructures, stability and other factors need to be verified. Therefore, the objective of this study is to analyze the sensitivity of soil properties to secure slope safety according to various heights of embankment when bottom ash and dredged soil mixture is applied in the embankment. In most cases, all heights were safe for the slide for the embankment whether the water level is full or sudden draw down. The result of the sensitivity analysis revealed that the unit weight of embankments is highest among all factors to be considered. However, the sensitivity of the unit weight became smaller and the sensitivity of the friction angle of embankments increased with the height of embankments. The sensitivity of factors of core materials is very small because the core has weaker physical properties than those of the embankment. The effect of the height for each factor is different for each slope and water levels. The sensitivity of the unit weight of embankments is most affected when the height is 60m in the upstream slope. To conclude, bottom ash and dredged soil mixture can be applied in the embankment and different factors must be considered in different scale because the sensitivity depends highly on the height of embankments.

• Journal of Korean Tunnelling and Underground Space Association
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• v.10 no.4
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• pp.329-336
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• 2008

Efficient traffic network is required in urban area for good living condition. However, dense traffic network creates traffic jam and gives bad influences to the ground environment. Therefore, advanced use of underground and tunnel is required. But, in the last 20 years many tunnel fire accidents have occurred all over the world. Increase of tunnels and increase of traffics result in increase of tunnel fire. Tunnel fire creates damage to people and to the tunnel structure. Also, tunnel fire creates a big economical loss. In a mountain tunnel, the stability of the tunnel will not be disturbed by fire although the tunnel lining will get a severe damage. However, in a shield tunnel or immersed tube tunnel, cut and cover tunnel, there is a high possibility that tunnel itself will collapse by fire because their tunnel concrete lining is designed as a structural member. The aim of this experimental research is to verify the fire protection performance of newly developed cementitious material compared with the broadly used existing products in Europe and Japan. For the experiments, the general NATM tunnel concrete linings with the newly developed material were tested using fire loading curve of RABT (Maximum peak temperature is $1,200^{\circ}C$) and RWS (Maximum peak temperature is $1,350^{\circ}C$). From the test results, the newly developed fire protection material applied with 30 mm thickness showed good fire-proofing performance under RABT fire loading.

• Journal of Wetlands Research
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• v.18 no.2
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• pp.194-200
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• 2016

The impervious surface rate increased by urbanization causes various problems on the environment such as water cycle distortion, heat island effect, and non-point pollutant discharges. The Low Impact Development (LID) techniques are significantly considered as an important tool for stormwater management in urban areas and development projects. The main mechanisms of LID technologies are hydrological and environmental pollution reduction among soils, media, microorganisms, and plants. Especially, the media provides important functions on permeability and retention rate of stormwater runoff in LID facilities. Therefore, this research was performed to assess the pollutant removal efficiency for different types of media such as zeolite, wood chip, bottom ash, and bio-ceramic. All media show high pollutant removal efficiency of more than 60% for particulate materials and heavy metals. Double layered media is more effective in reducing heavy metals by providing diverse sizes of micro-pores and macro-pores compared to the single layered media. The results recommend the use of different sizes of media application is more cost-effective in LID than a single size of media. Furthermore, soluble proportion of total heavy metal in the stormwater is an important component in proper media selection and arrangement.

• Journal of Wetlands Research
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• v.17 no.3
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• pp.228-236
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• 2015

Urbanization causes many environmental, hydrological and ecological problems such as distortion of the natural water circulation system, increase in nonpoint source pollutants in stormwater runoff, degradation of surface water quality, and damage to the ecosystem. Due to the increase in impervious surface by urbanization, developed countries apply low impact development (LID) techniques as important alternatives to reduce the impacts of urbanization. In Korea, LID techniques were employed since 2012 in order to manage nonpoint source pollutants. LID technology is a technique for removing pollutants using a variety of physical, chemical and biological mechanisms in plants, microorganisms and filter media with the reduced effluence of stormwater runoff by mimicking natural water circulation system. These LID facilities are used in a variety of filter media, but an assessment has not been carried out for the comprehensive comparison evaluation of adsorption and desorption characteristics for the pollutant removal capacity. Therefore, this study was conducted to analyze the adsorption and desorption characteristics of various filter media used in the LID facilities such as sand, gravel, bioceramic, wood chips and bottom ash etc. in reducing heavy metals(Pb, Cu). In this study, the adsorption affinity for Pb in all filter media was higher than Cu. Pseudo second order equation and Langmuir-3 isotherm are more applicable in the adsorption kinetic model and adsorption isotherm model, respectively. As a result of the desorption experiment, the filter media does not exceed KSLT which is the hazardous substance leaching limit, showing the capability of the filter media in LID. The bioceramic and woodchip as filter medias were evaluated and exhibited excellent adsorption capacity for Pb.

• Journal of Wetlands Research
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• v.17 no.1
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• pp.53-61
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• 2015

Habitat creation for endangered species Menyanthes trifoliata L. using planting module represents a habitat type such as the rhizome grows horizontally to open water at the margin of the lake. The objectives of this mesocosm experiment are habitat creation with easy construction and low management effort, and to investigate the potential of providing a habitat for aquatic macroinvertebrates. Planting modules had three different substrates of bed soil, perlite and K-SOIL (artificial lightweight soil using bottom ash). These modules were established in two different size of the tub($1170{\times}2250{\times}300mm^3$, $900{\times}1360{\times}190mm^3$). According to the monitoring results, number of leaves and coverage of M. trifoliata showed significant difference with substrate and tub size. The number of leaves showed similar growth responses in bed soil (mean 22.979) and K-SOIL (mean 28.042) substrates but growth was poor in perlite substrate (mean 1.667). The number of leaves in the large tub was more than small tub (p=0.015). Similar responses were obtained with the coverage, the length of rhizome and the number of rhizome in M. trifoliata. A total of 21 taxa of aquatic macroinvertebrates including 1,145 individuals was found in the mesocosm. The Shannon diversity index and colonization index in the mesocosm were similar to the previous studies. These results suggest that the experimental mesocosm could provide sufficient habitats for aquatic macroinvertebrates. If planting modules use bed soil or K-SOIL by planting substrate, establish that taking into account open water surfaces for M. trifoliata growth and manage about 30cm of water depth control, then habitat creation for M. trifoilata will be successful.