• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.905-908
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• 2006

In this study examines physical and mechanical properties the use of domestic low grade meta-kaolin in light weight porous concrete. For this purpose light weight porous concrete incorporating low grade meta-kaolin admixture, was tested for tensile strength and acoustic characteristics. Checking tensile strength of cement and low grade meta-kaolin mixture was used to determine the optimum mix proportion of the low grade meta-kaolin admixture. In this paper sound absorbing material has been investigated by using the light weight porous concrete.

• 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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• 2018.11a
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• pp.19-20
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• 2018

As energy related problems continue to arise, Korea's thermal insulation market for the zero energy homes is also demanding major changes, but there are no realistic countermeasures. Also, interest in inorganic insulation is growing as damage from multifamily housing fire using flammable insulation materials is increasing. On the other hand, many studies have been conducted on lightweight foam concrete, which implies a sufficient possibility as an insulation material by generating a large amount of air bubbles. However, studies of existion bubble concrete are not quantified by the experimental difficulty of using bubbles when compared. Therefore, in this study, the change in strength due to air pressure using a bubble foam, one of the types of air bubbles for the development of light foam concrete.

• Journal of the Korea Concrete Institute
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• v.18 no.6 s.96
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• pp.743-748
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• 2006

This paper presents results of an experimental study conducted to investigate the effect of volume fraction of fibers on the mechanical properties of a fiber-reinforced, lightweight aggregate concrete(FRLAC) that was produced without an autoclave process. The FRLAC enhanced the strength of lightweight, cellular concrete by adding polypropylene fibers and lightweight aggregates. To investigate the effect of volume fraction of fibers on the mechanical behavior of FRLAC and to determine the optimal volume fraction of fibers, a series of compression and flexural strength tests on FRLAC specimens with various fiber volume fractions(0%, 0.10%, 0.25%, 0.50%) were conducted. It was observed from the tests that a 0.25% volume fraction of fibers maximized the increase in the strength of FRLAC and the fibers controlled cracking in FRLAC.

• Journal of the Korea Concrete Institute
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• v.24 no.1
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• pp.61-70
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• 2012

Recently, the government has been working feverously to save energy and reduce greenhouse gas emission by enacting Basic Act on Low Carbon Green Growth at the national level. Improving the insulation performance of building exterior and insulator can reduce the energy in the building sector. This study is about developing light-weight foamed concrete insulation panel that can be applied to buildings to save energy and to find the optimal condition for the development of insulation materials that can save energy by enhancing its physical, kinetic and thermal characteristics. Various experimental factors and conditions were considered in the study such as foam agent types (AES=Alcohol Ethoxy Sulfate, AOS=Alpha-Olefin Sulfonate, VS=Vegetable Soap, FP=Fe-Protein), foam agent dilution concentration (1, 3, 5%), and foam percentage (30, 50, 70%). Experiment results indicated that the surface tension of aqueous solution including foam agent, was lower when AOS was used over other foam agents. FP produced relatively stable foams in 3% or more, which produced unstable foams containing high water content and low surface tension when diluted at low concentration. Depending on foam agent types, compressive strength and thermal conductivity were similar at low density range but showed some differences at high concentration range. In addition, when concentrations of foam agent and foaming ratio increased, pore size increased and open pores are formed. In all types of foam agent, thermal conductivity were excellent, satisfying KS standards. The most outstanding performance for insulation panel was obtained when FP 3% was used.

• Journal of The Korean Digital Architecture Interior Association
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• v.12 no.1
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• pp.81-88
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• 2012

According to the survey results of the Ministry of Land, Transport and Maritime Affairs in the end of December 2011, the residential buildings was reported as 67.3% of 4,529,464 buildings. Reflected in the national energy policy, the residential building is expected that greater energy savings. To have realized the Passive House Project used the Autoclaved Lightweight Concrete(ALC) material on exterior wall, we take advantage of a very large energy savings. Therefore, this study investigate the patent documents of three major companies, SUMITOMO, CLION, ASAHI KASEI, in Japan. and analyze technical flow and benchmarking patent. As a result, the Sliding method or the Rocking method of ALC panels how to install is to be superior to high-performance drift and safety by a earthquake. And the embedded anchor in panel needs to improve the shape and the strength of bearing. Thus installation technology of the ALC exterior wall investigated in japanese patent documents is expected to the fastening units and anchors.

• Journal of The Korean Digital Architecture Interior Association
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• v.11 no.3
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• pp.35-42
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• 2011

The exterior system of buildings, which is the typical curtain wall, has been made with glass and metal. Theses materials, however, have weaknesses such as inadequate insulating quality, short durability, combustibility and toxic substance. On the other hand, Autoclaved Aerated Concrete(AAC) or Autoclaved Lightweight Concrete(ALC) possess the great energy efficiency and the superb insulating quality as substitute of existing exterior system materials. In this research, strength characteristics and bubble dispersion of hydrothermal synthesis process of AAC based on CaO/$SiO_2$(C/S) ratio are analyzed. C/S ratio is determinated and bubble distribution and compressive strength are studied through the test of varied water-to-solid mineral ratio(W/S). In hydrothermal synthesis program, final C/S ratio is determined as 0.7 consider of the manufacturing process and hydrothermal synthesis is done at $180^{\circ}C$ for 7 hours. The analysis shows slurry has about 2,300cP viscosity and 0.56 specific gravity therefore it is expected AAC has the appropriate facility in the manufacturing process and Hydrates of AAC's Expansion.

• Journal of The Korean Digital Architecture Interior Association
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• v.11 no.4
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• pp.21-27
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• 2011

These materials in architecturally glass or metal have weaknesses such as inadequate insulating quality, combustibility and toxic gases in fires substance. However, Autoclaved Lightweight Concrete(ALC) has excellent thermal insulation properties and seem to possess the superb insulating quality as substitute of existing exterior materials. This research is to compare experimentally to the kind of the strength properties of ALC materials which mixed with blast furnace slag pounder and silica fume. For the purpose of increasing the strength, the plastic states of ALC evaluate the physical characteristics as microstructure and strength according to various specific gravity. According to the quicklime quantity the compressive strength is proportionate depend on the absolute dried specific gravity. When not putting in 10% quicklime, the compressive strength appeared most lowly with 14.0MPa. When putting in the quicklime, the strength appeared higher with 15.1MPa. And strength of specimen containing 2.25% silica fume is 15.6MPa increased 10.3% than reference specimen 14.0MPa.