• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.1
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• pp.37-43
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• 2019

This research studied production of lightweight filling production for sink hole restoration utilizing various industrial by-products(2kinds of fly ash, petro-cokes CFBC ash, blast furnace slag fine particle). For this purpose, the mixed raw material properties(compressive strength) behaviors according to the blending ratio of industrial by-products were examined by applying the experimental design method and statistical analysis was performed using the commercial program MINITAB. Compressive strengths of industrial by-products were strongly dependent on blast furnace slag powder. Compressive strength(3days aging) was 3~11MPa depending on the amount of blast furnace slag powder used. The use of CFBC fly ash was evaluated to have the least effect on compressive strength. In addition, the compressive strength and the coefficient of permeability were measured by preparing foamed concrete for the experimental batch 1 condition in the mixture experimental design. In this case, the bulk density is 0.9 to 1.0, the apparent porosity is 30 to 50%, the compressive strength(3days old) is 1 to 2MPa, and the permeability coefficient is $10^{-2}$ to $10^{-3}cm/sec$.

• Journal of the Korean Recycled Construction Resources Institute
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• v.2 no.2
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• pp.166-171
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• 2014

This experimental study considers manufacturing method of the non-portland cement matrix for the light-weight building materials using blast furnace slag, paper ash, fly ash and polysilicon sludge the industrial by-product. For the experiment, we used paper ash by means of the foaming agent and alkali activator to make non-portland cement light-weight matrix. Various specimens were prepared with different types and addition ratios of the alkali activator. Then, the properties of these specimens were investigated by compressive strength test, bulk specific gravity. As a results, it was judged that experiment results of non-portland cement matrix with specific waste resources and alkali activators were useful as basic data for mixtures design and evaluation properties of lightweight non-portland cement building material.

• KIEAE Journal
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• v.10 no.3
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• pp.89-96
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• 2010

In comparison with ordinary or heavy-weight concrete, light-weight air void concrete has the good aspects in optimizing super tall structure systems for the process of design considering wind load and seismic load by lightening total dead load of buildings and reducing natural resources used. Light-weight air void concrete has excellent properties of heat and sound insulating due to its high amount porosity of air voids. So, it has been used as partition walls and the floor of Ondol which is the traditional Korean floor heating system. Under the condition of which the supply of light-weight aggregates are limited, the development of light-weight concrete using air voids is highly required in the aspects of reduced manufacturing prices and mass production. In this study, we investigated the physical properties and thermal behaviors of specimens that applied different mixing ratios of foaming agent to evaluate the possibility of use in the structural elements. We proposed the estimating equation for compressive strength of each mix having different ratio of foaming agent. We also confirmed that the density of cement matrix is decreased as the mixing amount of foaming agent increase up to 0.6% of foaming agent mixing ratio which was observed by SEM. Based on porosity and compressive strength of control mortar without foaming agent, we built the estimating equations of compressive strength for mortars with foaming agent. The upper limit of use in foaming agent is about 0.6% of the binder amount. Each air void is independent, and size of voids range from 50 to $100{\mu}m$.

• Magazine of the Korea Concrete Institute
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• v.9 no.2
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• pp.137-144
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• 1997

The effcct of specific g~avity cont~olled In the .range fiom O.4 to 0.7 by particle size and added amount of A1 powder in the presence or absence of water repellent agent on the physical properties of ALC was examined to evaluate frost resistance and durability. The compressive sttcngth and the tensile strength are increased and independency with water repellent agent when the specific gravity is increased in the range from 0.4 to 0.7. According as the added amount of water repellent agent was increased. frost resistance was improved and absorption ratio was decreased. ALC produced from fine Al powder has a low volume reduction by scaling and a sound apperance after freezing/thawing test and top surface freezing test.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.11a
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• pp.19.2-19.2
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• 2009

금속을 용해 응고시킬 때 생성되는 소위, 주조 결함이나 소결금속 내의 기공은 재료의 성능이나강도를 현저하게 낮추는 결함으로서 예전부터 기피되어 왔다. 또한, 재료공정에있어서도 여하의 기공이나 기포가 없는 치밀한 고강도 및 고기능성 재료를 개발하는 것에 최대한의 주의와 관심을 기울여 왔다. 그렇지만, 우리가 자연계의 천연물이나 인공물을 둘러보면 그 대부분이다공질임을 쉽게 눈치챌 수 있다. 예를 들어 목재, 지엽등의 생물을 시작해서 콘크리트 등의 인공물, 우리 체내의 뼈도 전형적인 다공질구조로 구성되어 있다. 이러한 구조로부터 재료의 재질제어 이외에 구조제어라는 새로운 어프로치를 고려할 수 있고, 최근 들어, 금속재료에 있어서도 이러한 다공질구조에 관한 연구가활성화되어 충격흡수재, 생체재료, 베어링재료 등의 다양한응용이 전개되고 있다. 특히, 원주상의 방향성 기공을 갖는 로터스금속은 기존의 복잡한구조의 다공질금속보다 뛰어난 기계적 성질을 갖는다. 이러한 다공질금속은 일방향응고할 때 생성하는 과포화가스원자를 석출시켜 기공을 일방향으로 성장시킨다. 즉, 융점에서의 고상과 액상의 가스 용해도 차를 이용하는 것으로서 응고시에 고용할 수 없는 가스원자가 기공을 형성한다. 이와같이 제조한 방향성 다공질금속은 BT (인플란트, 생체적합성, 저탄성, 경량), ST (초음속기엔진부품, 경량), IT (고성능수냉모듈), ET(고온촉매, 필터)의 분야로의 응용이 기대된다. 본 강연에서는 방향성 다공질금속의 제조법, 특성 및 응용을 포함하여그 동안의 연구성과 및 앞으로의 과제 등을 소개하고자 한다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.11a
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• pp.57-60
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• 2006

This study proposes the physical properties of the hardened lightweight cement using the polyethylene tube and to make the fundamental data regarding a new lightweight concrete development. The aerated concrete is displaying various effects such as lightweight, insulation characteristic and it is coming to be widely applied the slab layer of apartment as an insulating material but currently the aerated concrete has many problems. Therefore, demonstrating similar property of former aerated concrete and improving the defects, developing new hardened cement is needed. In this study, we predict adopting possibility of hollow core polyethylene tube, as a material to make cement hardening containing a lot of void. So we changed the mixing ratio, a diameter and length of the polyethylene tube and improved the compressive strength and unit capacity weight of the lightweight cement hardening body. From the test results, we judge that the aerated concrete is a developmental possibility.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.67-70
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• 1992

1930년 스웨덴에서 개발에 성공, 네덜란드에서 더욱 발전시킨 ALC(Autoclaved Light-weignt Concrete의 약칭) 는 가볍고, 견고하고, 그리고 시공이 간편한 경제적인 요건들을 충족시키는 건축자재로 세계적으로 널리 사용되고 있으며 , 국내에서는 불과 수년 전부터 연구 개발되고 있는 실정이다. ALC 란 시멘트와 규사, 생석회등 무기질 원료를 고온,고압으로 증기 양생시킨 경량의 기포 콘크리트 제품을 통칭한 것이다. ALC공정은 bulk ALC를 생산하는 batch공정과 이 bulk ALC에 대한 처리 공정으로 크게 나눌 수가 있으며 여기에서는 bulk ALC 처리 공정을 side shield treatment, anti-corrosion treatment, curing grate transferer, cutting station, curing car transportation, autoclave traveling platform, 및 packing 의 공정으로 세분하여 각 공정개요 소개 및 PLC(Programmable Logic Controller의 약칭)를 이용한 제어 system에 대하여 설명하고자 한다.

• 월간 기계설비
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• s.143
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• pp.60-74
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• 2002

건축물의 에너지 이용을 효율화하기 위하여 단열기준 등을 기존보다 20% 이상 강화하는 것을 골자로 하는 건축물의 에너지절약 설계기준(건설교통부 고시 제2001-118호)이 지난해 6월 1일부터 시행되고 있다. 개정 기준의 가장 큰 특징은 단열기준의 적용 부위를 외기에 직접 면한 부위와 간접 면한 부위로 구분하고, 지역을 중부와 남부, 제주도로 구분$\cdot$설정하여 부하조건과 에너지 소비특성에 따라 건축물의 단열기준을 세분화한 것이다. 특히, 종래에는 최하층 바닥에만 적용하였던 거실 바닥(온돌)의 단열기준을 중간층까지 확대$\cdot$적용하였고, 여기에 온돌시스템의 열적 특성을 고려하여 단열기준의 적용 부위를 보다 구체적으로 설정하고 있다. 따라서 종래의 온돌시스템에서 채움층으로 일반적으로 사용하고 있는 현장 타설식 경량기포콘크리트의 열전도율이 0.13W/mK 내외임을 고려한다면 현행 습식온돌시스템의 열관류율은 $1.0W/m^{2}K$ 이상이 될 것으로 예상됨으로서 앞으로 온돌시스템의 배관층 하부에 $1.0m^{2}K/W$ 이상의 열전도저항을 지닌 단열층이 구성되어야만 개정기준에서 정하는 열관류율 $0.81W/m^{2}K$(기준층 기준)의 성능과 배관하부의 열전도저항값 적용비율을 만족할 수 있을 것으로 판단된다.

• Journal of environmental and Sanitary engineering
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• v.16 no.1
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• pp.102-107
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• 2001

This research was carried out investigate the removed T-P, T-N and anion surfactants using Autoclaved Lightweight Concrete(ALC) in wastewater treatment system. Effects of pH, TDS on aqueous solution was measured. Specific area which measured by BET was $27.66m^2/g$. The phosphorous, nitrogen and anion surfactants removal efficiencies were examined by using artificial waste water(T-P : 66~73mg/L, T-N : 56~136mg/L and anion surfactants : 10~31mg/L). The results showed that the ALC was effective material as a adsorbent due to the structure and porosity. It was found that anion surfactants removed was 85~95%, phosphate removed was 92% and nitrogen removed was 90% in artificial wastewater. Agitation process was more effective than aeration process in that case of nitrogen removal system using ALC.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.955-958
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• 2006

The purpose of this study is to find ways of recycling a great amount of gypsum as by-product from the manufacture of phosphate fertilizer. For the purpose, this researcher investigated physical properties of light weight Porous material using waste gypsum and a foaming agent, Sodium n-dodecyl Sulfate to utilize it as a interior material of construction. To determine such properties, the study examined pore size distribution and pore rate in accordance with contents of Sodium n-dodecyl Sulfate added. Then expanded vermiculite as light-weight aggregate was also added, when pore size distribution, pore rate and sound absorption rate were surveyed and measured.