• Journal of the Korean Crystal Growth and Crystal Technology
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• v.18 no.5
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• pp.211-216
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• 2008

The artificial lightweight aggregate (ALA) was manufactured in a rotary kiln at $1125^{\circ}C$ using green body formed by pelletizing the batch powder composing of coal bottom ash (CBA) produced from power plant, clay and dredged soil (DS). The TCLP (Toxicity characteristic leaching procedure) results showed that the dissolution concentration of heavy metal ions of ALA fabricated in this study was below the limitation defined by the enforcement regulations of wastes management law in Korea. The ALA containing 60$\sim$70 wt% CBA had a bulk density of 1.45$\sim$1.49 and a water absorption of 17.2$\sim$18.5 %. The impact values for oven-dry state and saturated-surface dry state of ALA were 27.4$\pm$1.3 and 23.4$\pm$2.6 % respectively. The 28-days compressive strength of concrete made with various ALA was $22.7\sim27.8 N/mm^2$. The slump of concrete with ALA containing CBA 60 and 70 wt% were 7.9 and 14.3 cm respectively. The unit weight of concrete made with any ALA fabricated in this study was satisfied with the standard specifications of lightweight concrete for the civil engineering and construction presented by Korea as below $1.84 ton/m^3$.

• Journal of the Korea Concrete Institute
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• v.15 no.6
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• pp.840-847
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• 2003

Recently, the coal-ash production has been increased by increase of consumption of electric power. So it is important to secure a reclaimed land and treatment utility for coal-ash. This is an experimental study to compare and analyze the engineering properties of concrete according to W/C and replacement ratio of bottom ash. For this purpose, the mix proportions of concrete according to W/C(40, 50, 60%) and replacement ratio of bottom ash(0, 10, 20, 35, 50%) were established, and then tested for slump, chloride content, setting time, bleeding content, compressive strength. Also the durability test of concrete with W/E 60% was performed. According to test results, it was found that the bleeding content of concrete decreased as the replacement ratio of bottom ash increased. And the chloride content of concrete using the bottom ash increased as the replacement ratio of bottom ash increased, but it is satisfied with the chloride content of fresh concrete $0.30kg/m^3$ below("concrete standard specification" regulation value). The compressive strength of concrete using the bottom ash was similar to that of BA0 concrete after 28 days of curing and the carbonation depth of concrete was increased according to increase of the replacement ratio of bottom ash.