• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.631-636
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• 2002

This study shows basic data for using as the structural lightweight aggregate. This will be the procedural method of recycling environmental close waste PET bottle lightweight aggregate(PBLA) that is rapidly increased the amount of production of waste PET bottle recently, the quality of developed PBLA and the fundamental properties by analyzing of mortar containing with PBLA. After experiment, the result shows the PBLA quality that have oven dry specific gravity of 1.39, unit volume weight of 844 kg/m$^3$ and absorption rate of 0% is satisfied with qualify regulation of lightweight aggregate. The flowability of mortar containing PBLA is increased maximum 16% with increasing mixing ratio of PBLA, however the compressive strength of mortar is decreased maximum 35% with increasing mixing ratio of PBLA.

• Journal of the Korean Ceramic Society
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• v.53 no.2
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• pp.241-245
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• 2016

The purpose of this study was to investigate the bloating mechanism of artificial lightweight aggregates with different sizes (ESA, effective surface area). Aggregates were produced using hard clay, stone sludge, and a bloating agent in order to observe the effect of the gradation of the artificial lightweight aggregates. Kerosene and amorphous carbon were used as bloating agent. The particle size of the produced aggregate ranged from 3 mm to 9 mm. With regard to the amount of bloating agent to be used, 2 ~ 6 parts by weight were used. The specific gravity, absorption rate, and the type of aggregates produced by rapid sintering at $1075{\sim}1200^{\circ}C$ were determined. Microstructures were observed. When ESA had a value of 1 or below, kerosene, which has a high burning rate, was found to be advantageous for use as a bloating agent. When ESA had a value of 1 or above, carbon, which has a relatively low burning rate was found to be an advantageous bloating agent. It is thought that kerosene is more advantageous, as ESA decreases, for the production of aggregates having low water absorption rate.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.565-570
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• 2001

Annually, Taiwan generates approximately 2 million tons of inorganic wastes in the form of sludge, fly ash and slug. To increase the added value of waste and maintain the increasingly insufficient supply of natural gravel, large public construction projects account for this large demand each year. future architectural trends are leading towards high-rise buildings. In light of the above, Center for Environmental, Safety and Health Technology Development, Industrial Technology Research Institute has developed the technology of manufacturing cold-bonding, sintering and bloating types of lightweight aggregates with a specific gravity ranging between 0.7~1.7, water absorption rate < 30%. The lightweight aggregate verified by physical property tests can be used as a substitute for the natural aggregate, which generally appears in replacing gravel in concrete, soundproofing and heat insulation materials. Doing so would not only moderate waste disposal problems, but also achieve the goal of resource recovery.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.409-410
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• 2023

In this study, the compressive strength and ultrasonic pulse velocity were evaluated according to the elapsed time on concrete mixed with normal and lightweight aggregates at early age. For evaluation in various strength ranges, the design compressive strength was set to 30, 45, and 60MPa and evaluated. As a result of the experiment, the compressive strength of concrete mixed with lightweight aggregates developed 5MPa earlier compared to normal aggregate concrete, and the UPV showed a similar tendency.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.7
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• pp.20-26
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• 2003

The ultra-lightweight high strength polymer concrete could be used for the drain structures under severe condition. In this study, materials used were unsaturated polyester resin, heavy calcium carbonate, artificial lightweight coarse aggregate and perlite. In the test results, the unit weight of the ultra-lightweight high strength polymer concrete was 946 kg f/$\textrm{m}^3$ and the compressive strength was appeared in 34.5 MPa. The compressive strength, splitting tensile strength, flexural strength, acid resistance and weather resistance were shown in excellently than that of the normal cement concrete. The draining trench had 1m length, 0.24 m width, 0.02 m thickness and 0.07 m height. The developed trench could be effectively used at the draining structures.

• Computers and Concrete
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• v.8 no.6
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• pp.617-629
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• 2011

In this investigation, reservoir sediment and municipal sewage sludge were sintered to form the artificial lightweight aggregates. The sintered aggregates were compared with the commercialized lightweight aggregates to in terms of potential alkali-silica reactivity and chemical stability based on analyses of their physical and chemical properties, leaching of heavy metal, alkali-silica reactivity, crystal phase species and microstructure. Experimental results demonstrated that the degree of sintering of an aggregate affected the chemical resistance more strongly than did its chemical composition. According to ASTM C289-94, all potential alkali-silica reactivity of artificial lightweight aggregates were in the harmless zone, while the potential reactivity of artificial lightweight aggregates made from reservoir sediment and municipal sewage sludge were much lower than those of traditional lightweight aggregates.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.271-272
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• 2010

This thesis is researched to compare the shrinkage of lightweight concrete depending on depth to normal concrete. It is used artificial lightweight aggregate which has 20% of pre-absorb value by lightweight concrete. When water-binder ratio is 30%, average shrinkage of lightweight concrete section decreased than normal concrete, but differential shrinkage of lightweight concrete section increased. However water-binder ratio is 40%, average shrinkage and differential shrinkage of lightweight concrete section decreased than normal concrete.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.227-228
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• 2010

Five lightweight concrete mixes were prepared to examine the effect of the replacement level of lightweight fine aggregates on the slump loss and compressive strength of lightweight concrete. Test results showed that the increase of the replacement level of lightweight fine aggregate accelerated the slump loss of the lightweight concrete, while had marginal influence on the compressive strength development of the concrete.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.6
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• pp.735-741
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• 2009

This study intends to evaluate the efficiency of non-point source reduction technique by using the porous lightweight and recycled aggregate which microorganism is seeded. In case of infiltration velocity 30~70 mm/hr in high concentration of influent, it is indicated that SS was 40~94%, COD 44~91%, BOD 4~91%, TN 1.2~66%, TP 7~70% of removal efficiency. Removal efficiency is good in infiltration velocity 30 > 50 > 70㎜/hr order. Therefore, the non-point source treatment facility filled with lightweight and recycled aggregate using microbial seeding shows higher removal efficiency than a conventional sand and gravel. We confirm that the function and efficiency are improved significantly and applied to treat non-point sources.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.339-344
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• 2000

The purpose of this study is to evaluate qualities of lightweight aggregate for structural concrete according to mixing proportions, pelletizer condition, sintering condition and to choose the suitable main and sub material. Main material used paper sludge ash(PSA) and sub material used clay, fly-ash and paper sludge. The aggregates are sintered after granulating at the various condition. As the result of test, quality difference of aggregate showed clear according to the mixing proportions and sintering conditions. It was possible to manufacture lightweight aggregate for structural concrete that dry specific gravity was ranged about 0.9 to 1.4 also the test results of the aggregates showed same physical properties compared with abroad product as 10% granules crushing value from 5 or 10% and absorption percentage from 10 to 20%.