• Journal of the Korea Institute of Building Construction
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• v.9 no.5
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• pp.63-70
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• 2009

This study is part of an ongoing research project on the development of a sound-absorbing lightweight foamed concrete manufactured by a hydro-thermal reaction between silica and calcium. As the silica source, pulverized bottom ash was used, and as several cementitious powders of ordinary portland cement, alumina cement and calcium hydroxide were used. Manufacture of foamed concrete was accomplished using the pre-foaming method to make a continuous pore system, which is the method of making the foam by using a foaming agent, then making the slurry by mixing the foam, water, and powders. The experiment factors are W/B, foam agent dilution ratio, and foam ratio, and test items are compressive strength, dry density, void ratio, and absorption rate, as evaluated by NRC. The experiment results showed that the sound absorption of lightweight foamed concrete satisfied NRC requirements for the absorbing materials in most of the experiments. It is thus concluded that foam ratio was the most dominant factor, and significantly affected all properties of lightweight foamed concrete in this study. W/B rarely affected total void ratio and continuous void ratio as well as compressive strength, and dry density and foam agent dilution ratio also had little effect onalmost all properties. The analysis of the correlation between NRC, absorption time, continuous void ratio, and absorption time showed that the interrelationship of the continuous void ratio was high.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.199-200
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• 2023

This paper presents a study on the selection of optimal mix proportions for producing lightweight pre-foam concrete as a substitute for Autoclaved Lightweight Concrete (ALC) without the accelerated curing. The study was conducted using a rapid hardening binder made from by-products of the steel industry as the primary raw material. The experimental results established the optimal mix proportions, which included retarder content, water/binder ratio, foam content, and fiber inclusion amount, for the production of lightweight foam concrete. The optimal mix proportion was determined to have a retarder content at the minimum amount required to secure the working time, W/B of 35%, a foam content limited to 65% or less, and a fiber inclusion amount of 0.05% or less.

• Korean Journal of Mineralogy and Petrology
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• v.33 no.4
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• pp.439-450
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• 2020

Global warming caused by the emission of greenhouse gases into the atmosphere is being treated as a major problem for the human life, and mineral carbonation is drawing attention as one of many countermeasures against this situation. In this study, mineral carbonation experiments using autoclaved lightweight concrete (ALC) were performed under various conditions to determine its potential as a carbonation material. ALC can be regarded as a promising material for carbonation because it contains about 27 wt.% of CaO, a major component of mineral carbonation. The CaCO3 content produced as a result of the carbonation of ALC calculated on the assumption that all of the CaO content participates in mineral carbonation is about 40 wt.%. The optimum conditions for the mineral carbonation reaction from ALC are the solid-liquid ratio of 0.01 and the reaction time of 180 minutes when calcite is considered as a single product, or 0.06 and 180 minutes when mixture of calcite and vaterite can be considered. The coexistence of vaterite with calcite at solid-liquid ratio of 0.06 or higher was interpreted to be the case where vaterite formed in the later stage and did not change to calcite until the reaction was completed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2007.11a
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• pp.53-56
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• 2007

Recently, waste concrete emission has been increased by acceleration of urban development and the rapid growth of redevelopment projects, so recycling of waste concrete is actively progressed, But the usage is limited to a lower value added such as the roadbed material etc. To produce the high quality recycled aggregate, breaking and washing process is added to the existing process and inevitably increases the occurrence of particle, because old mortal is included in the recycled aggregate. Therefore, this study purpose is analysis the properties of lightweight foamed concrete made by waste concrete sludge which is the by-product from produce the recycled aggregate. In result, possibility of manufacture of lightweight foamed concrete which gives equal performance compared with ALC was detect(scope of density : $0.5{\sim}0.6$, scope of compressive strength : $3.5{\sim}4.0MPa$). And scope of porosity is as follow ; total porosity : $27{\sim}30%$, open porosity : $1{\sim}5%$

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.168-169
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• 2019

This study examined the effect of foam volume ratio and curing temperature the air dry density and compressive strength of lightweight concrete using bottom ash. Test results showed that the lightweight concrete possessed the compressive strength of 3.4~22.7 MPa at the air dry density of 1,041~1,583 kg/m3.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1999.06a
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• pp.265-268
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• 1999

경량 건축소재는 협소공간의 고도 이용과 건설 분야의 양적, 질적인 측면에서 급속한 성장으로 건축자재의 경량화, 고급화 및 다양화를 요구하고 있으며 이에 PE, PP, PS, PVC 등의 플리스틱 foam 및 저밀도 콘크리트 등의 경량 건축 소재에 대한 연구가 지속되고 있다. 경량 건축소재로 사용되는 플라스틱류는 대부분 난연화 및 강도유지를 위해 난연제, 섬유 및 무기충진제 등를 첨가하거나 고밀도화하여 사용하며 경량화를 위해 foaming agent를 사용하여 기포를 발생시켜 경량화하여 성형된다. (중략)

• 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.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.132-133
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• 2014

In this study, high volume of industrial by-products including blast furnace slag, recycled aggregate powder and incineration ash have been utilized on the slurry of the foamed lightweight concrete. As to decrease the price of the lightweight foam concrete, mortar based slurry and concrete based slurry has been fixed. As the variation of the foam conduction ratio and aggregates, the foam ratio and compressive strength has been tested. Results showed that using recycled aggregates in the slurry showed better effect than using natural aggregates due to the alkali properties of the recycled aggregates could activate the potential hydraulic properties of the blast furnace slag. Consider about the low price of the recycled aggregates, it could be identified that using recycled aggregates in high volume blast furnace slag blended lightweight concrete showed better compressive strength than natural aggregates.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.189-190
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• 2016

Lightweight concrete is currently used at apartment buildings or housing construction sites causes some uneconomical problems due to excessive cracks and subsidences. So, it is in the situation that it is necessary to set up countermeasures against such subsidences. Therefore, in this study, it is intended to analyze the prevention of a subsidence inducing the expansion of the aluminum components depending on the changes of substitution rate and bubble mixing ratio by using the bubble-based Leavening Agent that Aluminum slag as an industrial by-product is substituted into some desulfurized plaster. As the results, it was found that the blending ratios, such as, the substitution ratio of bubble-based leavening agent (1%) and the bubble mixing ratio (65%) are appropriate while the flow property, subsidence depth and compression strength are considered.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2007.11a
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• pp.27-30
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• 2007

Recently, use of light-weight panel is increasing in building. Styrofoam sandwich panel is inexpensive and it is excellent in insulation ability and constructability. But styrofoam of panel inside is low ignition point. Consequently, when panel is fired, it is occur in poisonous gas. On the other hand, light-weight foamed concrete is excellent in insulation ability, fire resistance due to inner pore. Properties of light-weight concrete is influenced by foaming agent type. Accordingly, this study investigate in insulation property of according to foaming agent type in order to using light-weight foamed concrete instead of styrofoam. As a results, Non-heating zone temperature of light-weight foamed concrete of using AP, FP are lower than light-weight foamed concrete of using AES. Light-weight foamed concrete of using AES, FP are satisfied with fire performance of two hours at foam ratio 50, 100. Light-weight foamed concrete of using AP is satisfied with fire performance of two hours at AP ratio 0.1, 0.15. Insulation property is better closed pore by made AP, FP than open pore by made AES.