• Fire Science and Engineering
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• v.23 no.6
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• pp.116-125
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• 2009

This study is progressed function ratio, it's trued taste by an experiment to present data for human work light weight aggregate development that use clink ash progressed liquid limit, small success limit, wear loss in quantity, sand equivalent, sieve cutting examination. 80 : 20's match of function rain examination is 1.4, and that use rubble Goljae as ckink ash lightweight aggregate's capacity ratio increases by 1.0 increase of function rain many. Also, examination multiplied delicate flavor gradually according to increase of the mixing rate, and absorption coefficient increased. This is judged by phenomenon that appear by special quality upper clink ash of polystyrene bid and porosity's increase between lightweight aggregate. It is case that use aggregate of wear loss in quantity is 13.5 in sand equivalent and a wear loss in quantity experiment and although case that mix 20% increases by 14.4, this phenomenon by weak tissue of lightweight aggergate be judge. When it's as a these experiment, the statue prevention floor of a street improvement specifications is prescribing so that satisfy by sand equivalent 20, CBR 10. This is showed result that this satisfies in quality standard all in match experiment ago that see.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.247-250
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• 2012

As industrialization progresses is rapidly growing, the city of density and temperature is rising successively. It leads to the status of environmental issues. It is needed to develop process of planting concrete block using by Eco-materials for replacing to he existing rooftop light soil that imported. In this study, developing the process of planting lightweight block is researched on using applications of 6 Sigma technique. It makes process object improve standard by using statistical method. Also, there are suggestion that it is optimum mix design conditions and affection of experimental factors in matters of developing planting concrete block for rooftop greening.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.3
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• pp.202-209
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• 2019

The objective of this study is to examine the reproducibility for compressive strength development and mechanical properties of lightweight concrete made using bottom ash aggregates and foam(LWC-BF). Based on the mix proportions conducted by Ji et al., six identical mixes were prepared with different actual foam volume ratios from 0% to 25% and water-to-binder ratios from 25% to 30%. The presently measured properties, including initial slump, slurry density, compressive strength gains at different ages, splitting tensile strength, and modulus of rupture, were very close to those determined in the previous tests by Ji et al. Thus, the developed LWC-BF has a good potential in obtaining a reproducibility for compressive strength development and mechanical properties even though the troubles of mixing control owing to the addition of preformed foam.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.3
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• pp.216-223
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• 2019

The objective of this study is to propose a reliable stress-strain model in compression for lightweight concrete using bottom ash aggregates and air foam(LWC-BF). The slopes of the ascending and descending branches in the fundamental equation form generalized by Yang et al. were determined from the regression analyses of different data sets(including the modulus of elasticity and strains at the peak stress and 50% peak stress at the post-peak performance) obtained from 9 LWC-BF mixtures. The proposed model exhibits a good agreement with test results, revealing that the initial slope decreases whereas the decreasing rate in the stress at the descending branch increases with the increase in foam content. The mean and standard deviation of the normalized root-square mean errors calculated from the comparisons of experimental and predicted stress-strain curves are 0.19 and 0.08, respectively, for the proposed model, which indicates significant lower values when compared with those(1.23 and 0.47, respectively) calculated using fib 2010 model.

• Journal of Environmental Science International
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• v.16 no.10
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• pp.1169-1177
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• 2007

The main objective of this research was to evaluate the effects of process variables which were forming ability, flow displacement, effective stress, effective strain, fluid vector and products defects on manufactured artificial lightweight aggregate made of both incinerated sewage sludge ash and clay by means of the numerical analysis of a rigid-plastic finite element method. CATIA (3D CAD program) was used for an extrusion metal mold design that was widely used in designing aircraft, automobile and metallic molds. A metal forming analysis program (ATES Co.) had a function of a rigid-plastic finite element method was used to analyze the program. The result of extrusion forming analysis indicated clearly that a shape retention of the manufactured artificial light-weight aggregate could be maintained by increasing the extrusion ratio (increasing compressive strength inside of extrusion die) and decreasing the die angle. The stress concentration of metal mold was increased by increasing an extrusion ratio, and it was higher in a junction of punch and materials, friction parts between a bottom of the punch and inside of a container, a place of die angle and a place of die of metal mold. Therefore, a heat treatment as well as a rounding treatment for stress distribution in the higher stress concentration regions were necessary to extend a lifetime of the metallic mold. A deformity of the products could have made from several factors which were a surface crack, a lack of the shape retention and a crack of inside of the products. Specially, the surface crack in the products was the most notably affected by the extrusion ratio.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.3
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• pp.215-220
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• 1992

The rational methods of pavement design and analysis using the resilient modulus have been increasingly adopted by major advanced countries and many researches concerning the resilient characteristics of pavement materials as well as developement of reliable testing method have been actively performed. Accordingly, fundamental researches on the resilient modulus characteristics of domestic subgrade soils are very important. With want of aggregate due to the national constuction projects, it is siginificant to examine on the utilization of coal ash as pavement materials. The purpose of this study is to examine resilient modulus characteristics and to evaluate the relationship between MR and CBR by AASHTO testing method. The materials for this investigation are Coal Ash (Fly Ash, Bottom Ash) from 5 thermal-power-plants and 4 decomposed-granite-soils from central regions of Korea.

• Resources Recycling
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• v.16 no.3 s.77
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• pp.19-26
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• 2007

The bottom ash of municipal solid waste incineration generated during incineration of municipal solid waste in metropolitan area consists of ceramics, glasses, ferrous materials, combustible materials and food waste and so on. Although the ferrous material was separated by the magnetic separation before the incineration process, of which content accounts for about $3{\sim}11%$ in bottom ash. The formation of a $Fe_3O_4-Fe_2O_3$ double layer(similar to pure Fe) on the iron surface was found during air-annealing in the incinerator at $1000^{\circ}C$. A strong thermal shock, such as that takes place during water-cooling of bottom ash, leads to the breakdown of this oxidation layer, facilitating the degradation of ferrous metals and the formation of corrosion products and it existed as $Fe_2O_3,\;Fe_3O_4\;and\;FeS_2$. So, many problems could occur in the use of bottom ash as an aggregate substitutes in construction field. Therefore, in this study, the separation of ferrous materials from municipal solid waste incineration bottom ash was investigated. In the result, the ferrous product(such as $Fe_2O_3,\;Fe_3O_4,\;FeS_2$ and iron) by magnetic separator at 3800 gauss per total bottom ash(w/w.%) accounted for about 18.7%, and 87.7% of the ferrous product was in the size over 1.18 mm. Also the iron per total bottom ash accounted for about 3.8% and the majority of it was in the size over 1.18 mm.

• Journal of the Korea Concrete Institute
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• v.22 no.6
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• pp.851-858
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• 2010

In this study, waste glass and bottom ash were used as basic materials in order to secure a recycling technology of by-products which was mostly discarded and reclaimed. In addition, because softening point of waste glass is less than $700^{\circ}C$ and bottom ash includes combustible material, it was possible to manufacture low-temperature sintering lightweight aggregates for energy saving at $800{\sim}900^{\circ}C$ that it is as much as 20~30% lower than sintering temperature of existing lightweight aggregates. Thermal conductivity of newly-developed lightweight aggregates was 0.056~0.105W/m. K and its porosity was 40.36~84.89%. A coefficient of correlation between thermal conductivity and porosity was -0.97, it showed very high negative correlationship. With this, we were able to verify that porosity is key factor to affect thermal conductivity. Microstructure of lightweight aggregates by $CaCO_3$ content and replacement ratio of bottom ash in the variation of temperature were that $CaCO_3$ content increased along with pore size while replacement ratio of bottom ash increased as pore size decreased. Specially, most pores were open pore instead of closed pore of globular shape when replacement ratio of bottom ash was 30%, and pore size was small about 1/10~1/5 as compared with case in bottom ash 0~20%. In addition, open pore shapes were remarkably more irregular form of open pore in $900^{\circ}C$ than $700^{\circ}C$ or $800^{\circ}C$ when replacement ratio of bottom ash was 30%. We reasoned hereby that these results will influence on absorption increase, strength and thermal conductivity decrease of lightweight aggregates.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.247-248
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• 2010

This study is of manufacturing artificial lightweight aggregates using industrial wastes. The ingredients for manufacturing lightweight aggregate were stone sludge and bottom ash for main materials, and steel slag(SS), glass abrasive sludge(GS) and blast furnace slag(BS) respectively for accessory material. Their precursors were sintered in the range of $1,050{\sim}1,150^{\circ}C$ for 5 min. The sintered results show that the lightweight aggregate with SS had low water absorption ratio and density at $1,150^{\circ}C$. There's a possibility that if GS is used more than the range of this study, GS can be manufactured lightweight aggregate. But it is judged that BS are incongruent to be used for a raw material of lightweight aggregate.

• Journal of the Korean Ceramic Society
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• v.56 no.4
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• pp.365-373
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• 2019

Pond ash is a mixture of mostly coarser fly ash and bottom ash. The recycling rate of pond ash is low because pond ash is mixed with seawater and deposited in ponds. The pond ash is also subjected to natural weathering over a period of time. In this study, we investigated whether pond ash can be used as a raw material of geopolymers, without any purification process or through a minimal purification process. In addition, we investigated whether synthetic basalt made by adding foaming agent to geopolymer or casting it into a mold can show the surface of the natural basalt as it is. The highest 7-day compressive strength in geopolymers from pond ash without purification process was 26 MPa. The highest 7-day compressive strength in geopolymers from pond ash with impurities removed through dry sieve analysis was found to improve to 80 MPa. On the other hand, synthetic basalt made with geopolymer was shown to be more advantageous aesthetically when produced by casting it in a silicone mold rather than by adding a foaming agent. Non-purified pond ash can be made into geopolymers having low strength. Pond ash purified by sieving can, without use of an aggregate, be made into geopolymer having high-strength. Also, it is possible to produce synthetic basalt with the same appearance as natural basalt and sufficient strength for commercialization. This process will contribute to the mass consumption and recycling of pond ash.