시멘트 킬른더스트의 물성 및 이를 사용한 시멘트 모르터의 공학적 특성

한천구(Han Cheon-Goo),김성수(Kim Seong-Soo),황인성(Hwang Yin-Seong),차천수(Cha Cheon-Soo) 대한건축학회 2004 大韓建築學會論文集 : 構造系 Vol.20 No.11

In this paper, physical, chemical properties of CKD(Cement Kiln Dust) in each cement manufacturing company as well as engineering properties of cement mortar incorporating CKD are discussed in order to provide effective application method of CKD. According to test results, grain shape of CKD has an angular shape and same shape with grain of lime stone. Density of CKD is rather smaller than that of OPC(Ordinary Portland Cement) and blaine is greater than that of OPC more than 2~3 times. The hydration temperature of 10% CKD mortar is higher than that of OPC more than 3~4℃, but no hydration reaction of CKD in itself is observed. For chemical composition, main composition of CKD is CaO, CKD has a large loss on ignition. According to XRD analysis, highest peak point with CaCO3 is observed, which account for the same chemical composition with lime stone. For the properties of CKD mortar, an increase in now is observed with an increase in CKD content of 5%, and after that, it decreases. The use of CKD with 5% results in an enhancement of compressive strength. Especially, at 5℃ with an increase of CKD, strength development at early stage is enhanced due to acceleration of hydration reaction.

시멘트 킬른더스트의 치환 방법에 따른 콘크리트의 공학적 특성

한천구(Han Cheon-Goo),김성수(Kim Seong-Soo),황인성(Hwang Yin-Seong),차천수(Cha Cheon-Soo) 대한건축학회 2004 大韓建築學會論文集 : 構造系 Vol.20 No.4

In this paper, engineering properties of concrete are discussed using cement kiln dust(CKD) to find effective application method of industrial by-products. According to test results, for the effect of CKD contents of fresh concrete, fluidity and air content show decline tendency with increase of CKD contents due to improved viscosity and air void filling effect, Setting time shows to be accelerated due to enhanced hydration reaction of cement at early stage. For the effect of CKD replacement method on the compressive strength, replacement of CKD for fine aggregates achieve most favorable strength gain at early and late stage. For hydration heat, CaCO₃ and alkari in CKD play important role in accelerating initial hydration reaction, which cause higher hydration heat than that of plain concrete. For durability, replacement of CKD for fine aggregates shows desirable effect on improving drying shrinkage and accelerated neutralization test, while frost resistance shows to be decreased.

기포계팽창재 및 기포혼입율 변화가 경량기포 콘크리트의 품질에 미치는 영향

김민상 ( Min Sang Kim ),차천수 ( Cheon Soo Cha ),박도영 ( Do Yeong Park ),박용규 ( Yong Kyu Park ),김현우 ( Hyun Woo Kim ),한천구 ( Cheon Goo Han ) 한국건축시공학회 2016 한국건축시공학회 학술발표대회 논문집 Vol.16 No.1

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.

혼화재 치환 콘크리트의 압축강도 및 건조수축에 관한 연구

주은희(Joo, Eun-Hi),손명수(Shon, Myoung-Soo),전현규(Jeon, Hyun-Kyu),차천수(Cha, Cheon-Soo),김성수(Kim, Seong-Soo),한천구(Han, Cheon-Goo) 한국콘크리트학회 2005 한국콘크리트학회 학술대회 논문집 Vol.2005 No.5

혼화재 치환 콘크리트의 중성화에 관한 연구

주은희 ( Joo Eun-hi ),손명수 ( Shon Myeong-soo ),차천수 ( Cha Cheon-soo ),김성수 ( Kim Seong-soo ),한천구 ( Han Cheon-goo ) 한국구조물진단유지관리공학회 2005 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.9 No.1

This experimental study investigates compressive strength and neutralization of concrete incorporating mineral admixture, including CKD, FA and BS. For the properties of compressive strength, at 3 days, compressive strength of concrete incorporating cement kiln dust(CKD) was comparable to that of plain concrete, due to acceleration of early hydration of CaCO₃. On the other hand, at age of 91 days, concrete incorporating FA and BS exhibited higher strength gain than that of concrete incorporating CKD, due to pozzolanic and potential hydraulicity reaction. Increase of W/B ratio caused high neutralization depth. These of mineral admixture resulted in an increase in neutralization depth. This result can be illustrated by the fact that the incorporation of CKD resulted in an decrease in the cement contents, while alkali portion decreases due to pozzolanic reaction of FA and reduction of both Ca(OH)₂ and BS. Variation in physical properties of concrete is probably independent of the type of admixture used in this paper. The type of admixture did not affect any physical properties of concrete. However neutralization depth increased with an increase of M.A. contents.

혼화재 치환 콘크리트의 압축강도 및 황산염 침해 저항성에 관한 연구

주은희 ( Joo Eun-hi ),손명수 ( Shon Myeong-soo ),차천수 ( Cha Cheon-soo ),김성수 ( Kim Seong-soo ),한천구 ( Han Cheon-goo ) 한국구조물진단유지관리공학회 2004 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.8 No.2

This paper investigated the results of compressive strength and resistance to sulfate attack of concrete incorporating mineral admixtures. W/B, kinds and contents of mineral admixtures were selected as test parameters. According to test results, use of mineral admixtures resulted in a reduction of fluidity and air contents caused by increased fine particles and absorption effect of FA on reduction of AE agent. Thus, increase of SP and AE agent was needed to maintain the same fluidity and air content as plain concrete. At early stage, use of CKD was beneficial to the compressive strength while at 28days, incorporation of FA and BS had favorable effect on the compressive strength. For resistance to sulfate attack, age led to increase the length and mass loss and decrease of W/B resulted in decrease of the length and mass loss. This was attributed to the enhanced expansion resistance caused by sulfate attack in low W/B concrete.

혼화재 종류에 따른 콘크리트의 배합 및 압축강도 특성에 관한 연구

주은희 ( Eun Hi Joo ),손명수 ( Myeong Soo Shon ),한민철 ( Min Cheol Han ),차천수 ( Cheon Soo Cha ),김성수 ( Seong Soo Kim ),한천구 ( Cheon Goo Han ) 한국건축시공학회 2004 한국건축시공학회 학술발표대회 논문집 Vol.4 No.2

This paper investigated the results of mixture proportion and compressive strength of concrete incorporating mineral admixtures. W/B and contents of mineral admixtures were selected as test parameters. According to test results, use of mineral admixtures resulted in a reduction of fluidity and air contents caused by increased fine particles and absorption effect of FA on reduction of AE agent. Thus, increase of SP and AE agent was needed to maintain the same fluidity and air content as plain concrete. At early stage, use of CKD was beneficial to the compressive strength while at 28days, incorporation of FA and BS had favorable effect on the compressive strength.

CKD 치환 콘크리트의 강도 증진 해석

주은희 ( Joo Eun-hi ),손명수 ( Shon Myeong-soo ),조규일 ( Cho Kyou-il ),차천수 ( Cha Cheon-soo ),한민철 ( Han Mm-cheol ),한천구 ( Han Cheon-goo ) 한국구조물진단유지관리공학회 2004 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.8 No.1

In this paper, estimation of strength development of concrete incorporating cement kiln dust(CKD) is discussed using logistic model under various curing temperature and W/B. Compressive strength is gained with an increase in maturity. Before reaching 840°DㆍD of maturity, similar level of strength development is obtained regardless of CKD presence. Use of CKD has a beneficial effect on strength development of concrete at low curing temperature. Logistic model has a good agreement between measured strength and calculated strength. CKD concrete has slightly lower strength than plain concrete at same maturity. Resultant constant for estimating strength development of plain concrete calculated about 0.965 and for CKD concrete about 0.938. From the scope of the paper, effective strength control method and estimation model related to determine form removal time and protection period against frost damage at early age is provided by table 4 and Fig. 2.

혼화재 치환 콘크리트의 중성화에 관한 연구

주은희(Joo Eun-Hi),손명수(Shon Myeong-Soo),차천수(Cha Cheon-Soo),김성수(Kim Seong-Soo),한천구(Han Chean-Goo) 한국구조물진단유지관리학회 2005 한국구조물진단학회 학술발표회논문집 Vol.- No.-

This experimental study investigates compressive strength and neutralization of concrete incorporating mineral admixture, including CKD. FA and BS. For the properties of compressive strength, at 3 days, compressive strength of concrete incorporating cement kiln dust(CKD) was comparable to that of plain concrete, due to acceleration of early hydration of CaCO₃. On the other hand, at age of 91 days, concrete incorporating FA and BS exhibited higher strength gain than that of concrete incorporating CKD, due to pozzolanic and potential hydraulicity reaction. Increase of W/B ratio caused high neutralization depth. These of mineral admixture resulted in an increase in neutralization depth. This result can be illustrated by the fact that the incorporation of CKD resulted in an decrease in the cement contents, while alkali portion decreases due to pozzolanic reaction of FA and reduction of both Ca(OH)₂and BS. Variation in physical properties of concrete is probably independent of the type of admixture used in this paper. The type of admixture did not affect any physical properties of concrete. However neutralization depth increased with an increase of M.A. contents.

혼화재 치환 콘크리트의 압축강도 및 황산염 침해 저항성에 관한 연구

주은희(Joo Eun-Hi),손명수(Shon Myeong-Soo),차천수(Cha Cheon-Soo),김성수(Kim Seong-Soo),한천구(Han Cheon-Goo) 한국구조물진단유지관리학회 2004 한국구조물진단학회 학술발표회논문집 Vol.- No.-

This paper investigated the results of compressive strength and resistance to sulfate attack of concrete Incorporating mineral admixtures W/B, kinds and contents of mineral admixtures were selected as test parameters. According to test results, use of mineral admixtures resulted in a reduction of fluidity and air contents caused by Increased fine particles and absorption effect of FA on reduction of AE agent Thus, increase of SP and AE agent was needed to maintain the same fluidity and air content as plain concrete At early stage, use of CKD was beneficial to the compressive strength while at 28lays, incorporation of FA and BS had favorable effect on the compressive strength For resistance to sulfate attack, age led to increase the length and mass loss and decrease of W/B resulted in decrease of the length and mass loss This was attributed to the enhanced expansion resistance caused by sulfate attack In low W/B concrete