전기로 슬래그를 치환한 고로 슬래그 시멘트의 특성

이승헌,황해정,권성구,Lee, Seung-Heun,Hwang, Hae-Jeong,Kwon, Sung-Ku 한국세라믹학회 2006 한국세라믹학회지 Vol.43 No.7

Properties of slag cement that contained 50 wt% of blast furnace slag were studied when replaced blast furnace slag powder with electric arc furnace slag powder. Electric arc furnace slag was aged for about 2 months in the air by being crushed to be 1-3 mm in size. As a result of the experiment, it was proven that the water content for obtaining the same consistency became decreased as slag is replaced with electric arc furnace slag instead of blast furnace slag. Also, the workability of mortar increased about 30% at the same ratio of water to binder when blast furnace slag was completely replaced with electric arc furnace slag. The compressive strength of mortar on the 28 days increased when a slag replacement rate became 10 wt%, however, it rather decreased when the slag replacement rate exceeded 10 wt%. The heat of hydration became higher for the first 14 h in case of the replacement of slag cement by electric arc furnace slag. Yet, it decreased when 14 h had passed. Therefore, when all blast furnace slag was replaced with electric arc furnace slag, about 15 cal/g heat of hydration decreased when it passed about 72 h.

초미분말 서냉 슬래그를 혼화재로 사용한 콘크리트의 기초적 특성

허재혁,정성욱,허재원,임남기 한국건축시공학회 2009 한국건축시공학회지 Vol.9 No.2

In this study, a test has been carried out to solve the problem with ground granulated blast-furnace slag, low early strength & lack of supply and to find out a way to use as concrete admixture of the ultrafine blaine air cooling slag which is all disposed as the by product of air cooling slag and its test was conducted to the replacement rate of ultrafine blaine air cooling slag & mixing condition of every concrete admixtures by type for the purpose of obtaining later a basic data for practical use of the cement that used ultrafine blaine air cooling slag by conducting comparative analysis. If ultrafine-blaine air cooling slag is used to the concrete following the results, a high efficiency water reducing agent won't be needed much for flow acquisition due to a high increase in flow, and the stripping time of concrete form will be shortened thanks to the acquisition of early strength. And though, it has the problems with long term strength which is similar or a little lower than the 3 types of ground granulated blast-furnace slag, it's still applicable as the substitute materials for 3 types of ground granulated blast-furnace slag at 10, 15% replacement rate of ultrafine-blaine air cooling slag, at which it shows higher activation index than 3 types of ground granulated blast-furnace slag. In this study, a test has been carried out to solve the problem with ground granulated blast-furnace slag, low early strength & lack of supply and to find out a way to use as concrete admixture of the ultrafine blaine air cooling slag which is all disposed as the by product of air cooling slag and its test was conducted to the replacement rate of ultrafine blaine air cooling slag & mixing condition of every concrete admixtures by type for the purpose of obtaining later a basic data for practical use of the cement that used ultrafine blaine air cooling slag by conducting comparative analysis. If ultrafine-blaine air cooling slag is used to the concrete following the results, a high efficiency water reducing agent won't be needed much for flow acquisition due to a high increase in flow, and the stripping time of concrete form will be shortened thanks to the acquisition of early strength. And though, it has the problems with long term strength which is similar or a little lower than the 3 types of ground granulated blast-furnace slag, it's still applicable as the substitute materials for 3 types of ground granulated blast-furnace slag at 10, 15% replacement rate of ultrafine-blaine air cooling slag, at which it shows higher activation index than 3 types of ground granulated blast-furnace slag.

고로슬래그를 사용한 고강도 부순모래 콘크리트의 특성

최영화,김종인 대구대학교 산업기술연구소 2007 産業技術硏究 Vol.18 No.1

The purpose of this study is to analyse the properties of high strength crushed sand concrete in conditions of water binder ratios of 25, 30, 35% and blast-furnace slag substitutions of 0, 15, 30, 45%. Additionally, in case of water binder ratio of 30%, the maximum size of coarse aggregate is two kinds of 13, 19 mm. The conclusions of this study are as follows ; The loss of slump and slump flow of concrete increased according to higher blast-furnace slag substitution and smaller coarse aggregate. The loss of air content increased according to lower water binder ratio and higher blast-furnace slag substitution. The unit weight increased according to higher blast-furnace slag substitution and smaller coarse aggregate. The compressive strength appeared lower in early age as compared with that of plain concrete according to increasing of the blast-furnace slag substitution. However, the compressive strength was respectively 5, 6, 10% larger than that of plain concrete in case of 25, 30, 35% water binder ratios, 28 days, 30% blast-furnace slag substitution and 19mm coarse aggregate. According to increasing of the blast-furnace slag substitution, the modulus of elasticity and the tensile strength of concrete increased. The length change by the shrinkage increased when the larger coarse aggregate was used, and decreased according to higher blast-furnace slag substitution.

Statistical Analysis of the Physical Properties in a Slag-OPC-Gypsum System as a Compound Mixing Ratio

You, Kwang-Suk,Lee, Kyung-Hoon,Han, Gi-Chun,Kim, Hwan,Ahn, Ji-Whan The Korean Ceramic Society 2007 한국세라믹학회지 Vol.44 No.9

The effect of the mixing ratio of compounds in a slag-OPC-Gypsum system on the physical properties of Slag cement is investigated in this study. $Na_2SO_4$ was used as an alkali activator. Blast furnace slag cement was prepared from a mixture of blast furnace slag, ordinary Portland cement and anhydride gypsum. The fluidity and the compressive strength according to the ratio of each mixture were analyzed in statistical analyses in order to discover the parameters influencing the fluidity and compressive strength. The results showed that the hydration of blast furnace slag took place with the addition of $Na_2SO_4$ and that column-crystalline ettringite was created as the main hydration product of the blast furnace slag. In addition, it was found that the compressive strength of blast furnace slag cement tends to increase when the ordinary Portland cement content is higher up to three days. However, it is known that the compressive strength tends to increase as the blast furnace slag content becomes higher with increases in the level of OPC after 28 days. As a result of this analysis, it is believed that the ordinary Portland cement content influences the initial compressive strength of blast furnace slag cement, and that in later days this is highly influenced by the slag content.

고로슬래그를 사용한 콘크리트의 부착특성

라덕관 ( Deog-gwan Ra ),이경동 ( Gyeong-dong Lee ) 한국환경기술학회 2013 한국환경기술학회지 Vol.14 No.4

최근 우리나라에서는 하천골재가 고갈되고, 자연보호의 차원으로부터 자연골재는 물론이고 인공골재의 원료에 대해서도 채취 규제가 심하여 골재부족의 문제가 심각한 실정이다. 이에 대한 방편으로 제철소에서 생산되는 산업부산물인 고로수재슬래그의 사용량이 급격하게 증가하고 있으나 그의 여러 가지 특성에 대한 연구는 아직도 미비한 편이다. 본 논문에서는 수재사의 콘크리트용 잔골재로의 대체 가능성을 알아보기 위하여, 수재사로 잔골재를 치환한 콘크리트의 압축강도와 부착강도 특성을 알아보고, 치환율 변화에 따른 강도특성을 비교분석하여 보았다. 수재사를 사용한 콘크리트의 압축강도 및 부착강도는 수재사의 치환율이 커질수록 커지며 치환율 50%를 사용했을 때 슬럼프 및 강도면에서 최적임을 알 수 있었다. Recently, it is increasing use of blast-furnace slag. But there are a few research on the bond characteristics of concrete using blast-furnace slag, so it need to study about the blast-furnace blag. The purpose of this study is investigate of using ability the concrete which contain blast-furnace slag as fine aggregate. The test was performed for 4 kinds of samples with various ratio of W/C(45 %) and content of blast-furnace slag(replacement ratio : 0 %, 25 %, 50 %, 75 %). The concrete with 0 % slag content ratio means all of the fine aggregate is consist with coarse and fine aggregate. The compressive strength and bond strength properties of the concrete are examined at 28 days, and the test results are analyzed for each conditions with various correlation graphs. The results are summarized as follows. The slump is increased with the increase of slag content ratio. The maximum slump does not exceed the law slump value of normal concrete. but the slump is decreased with the over 50 % of slag content ratio. The compressive strength and bond strength is increased with the increase of slag content ratio, but the compressive strength and bond strength is decreased with the over 50 % of slag content ratio. And the variation rate of compressive strength and bond strength was largest when the slag content ratio is 50 %.

Enhancement of phosphorus removal with near-neutral pH utilizing steel and ferronickel slags for application of constructed wetlands

Park, J.H.,Kim, S.H.,Delaune, R.D.,Kang, B.H.,Kang, S.W.,Cho, J.S.,Ok, Y.S.,Seo, D.C. Elsevier Science 2016 Ecological engineering Vol.95 No.-

<P>The objective of this study was to enhance phosphorus (P) removal while achieving near-neutral pH in aqueous solution utilizing steel slags (Blast furnace slag, BFS; Basic oxygen furnace slag-air cooling, BOFS-A; Basic oxygen furnace slag-rapid cooling, BOFS-R) and ferronickel slag (FNS) for application to constructed wetlands (CWs). The maximum P adsorption capacities (mg kg(-1)) of the slags were in the order BOFS-R (3233) > BOFS-A (2320) >> BFS (607) > FNS (260) based on the Langmuir adsorption isotherm. The pH of the slags were in the following order: BOFS-R (11.9) > BOFS-A (9.0)>> BFS (8.9) > FNS (7.5). The basic oxygen furnace slags had the highest P adsorption capacity, while the ferronickel slag had the lowest pH among the tested slags. To achieve high P removal efficiency with near-neutral pH, the BOF slags and ferronickel slag (BOFS-A + FNS and BOFS-R +FNS) were mixed in batch experiments. To achieve effective P removal with near-neutral pH utilizing steel and ferronickel slags, the optimum conditions were found to be the ratio of BOFS-R:FNS of 7:3. Therefore, when mixed slags at the BOFS-R:FNS ratio of 7:3 were applied to CWs, they could achieve high P removal efficiency and near-neutral pH for meeting the acceptable drinking water quality discharge standard. (C) 2016 Elsevier B.V. All rights reserved.</P>

고로슬래그를 사용한 습식 순환 잔골재 모르타르의 강도 특성에 관한 연구

심종우 한국구조물진단유지관리공학회 2010 한국구조물진단유지관리공학회 논문집 Vol.14 No.5

고로슬래그 미분말을 순환골재 모르타르 및 콘크리트의 제조에 활용할 경우, 순환골재에서 용출된 Ca(OH)2가 고로슬래그에 대한 자극제 역할을 수행하여 수화반응을 개선할 수 있을 것으로 판단되고 고로슬래그를 통해 알칼리 저감 효과를 얻을 것으로 예상되어 본 연구를 진행하게 되었다. 그 결과 고로슬래그 미분말을 혼입․사용한 순환 잔골재 모르타르는 재령 3일에서는 고로슬래그 혼입율에 따라 강도가 감소하는 결과를 나타냈다. 이는 고로슬래그의 수화반응이 일어나지 않았기 때문으로 판단되며 또한, 순환 잔골재 혼입률에 관계없이 고로슬래그 미분말의 혼입률이 증가함에 따라 재령 3일 측정한 수화활성도도 저하되는 것으로 나타났다. 재령 7일에서는 순환 잔골재에서 용출된 수산화칼슘(Ca(OH)2)이 자극제 역할을 수행하여 고로슬래그 미분말을 혼입한 배합의 압축강도 발현이 천연 잔골재를 사용한 모르타르보다 서서히 증가하는 결과를 보이기 시작하였으며 이로 인해 재령 7일 측정한 고로슬래그 미분말을 단계별로 혼입한 배합의 수화활성도가 고로슬래그를 혼입하지 않은 배합보다 높아지는 것으로 나타났다. 재령 28일에서는 고로슬래그 미분말 혼입률 30% 배합에서는 고로슬래그의 수화반응으로 인해 천연 잔골재를 사용한 배합보다 높은 압축강도를 보이기 시작하였으며 이때 측정한 수화활성도는 천연 잔골재를 사용한 배합과 특별한 차이를 보이지 않았으며, 이는 지속적으로 수산화칼슘(Ca(OH)2)이 공급되지 못하였기 때문으로 판단된다. This study aims to obtain technical data for improvement of utilization of Blast Furnace Slag(BFS), recycled aggregate in the future by complementing fundamental problems of BFS such as manifestation of initial strength and excessive alkali quantity as well as weakness of recycled fine aggregate through manufacturing of recycled fine aggregate mortar using BFS. The recycled aggregate includes the cement paste hardened as the surface and the type of the aggregate, which contains plenty of calcium hydroxide(Ca(OH)2) as well as the unhydrated cement. Accordingly, the objectives of this study are to inspect the manufacturing the recycled fine aggregate mortar used with blast furnace slag, to consider the effects of the recycled aggregate on the strength development of ground granulated blast furnace slag, and then to acquire the technical data to take into consideration the further usages of the recycled aggregate and blast furnace slag. In eluted ions from recycled aggregate, it showed that there were natrium(Na+) and kalium(K+), expected to be flown out of unhydrated cement, as well as calcium hydroxide(Ca(OH)2). Application of this water to mix cement mortar with ground granulated blast furnace slag was observed to expedite hydration as calcium hydroxide(Ca(OH)2) and unhydrated cement component were expressed to give stimuli effects on ground granulated blast furnace slag. The results of the experiment show that the recycled aggregate mixed with blast furnace slag has comparatively higher hydration activity in 7 day than the mortar not mixed with one in 3 day mortar does, causing the calcium hydroxide in the recycled fine aggregate to work on as a stimulus to the hydration of ground granulated blast furnace slag.

고로슬래그 미분말을 혼입한 레디믹스트 숏크리트의 현장적용성에 관한 실험적 연구

최희섭,장필성,서신석,김동민 한국지반공학회 2009 한국지반공학회논문집 Vol.25 No.6

The aim of this study is to evaluate the applicability of Granulated Blast Furnace Slag to the development of the Powdered Ready-mixed Shotcrete. First of all, after accomplishing SEM analysis and Leaching Test, the laboratory and field experiments for evaluating the utility of Granulated Blast Furnace Slag were performed. As a result of SEM and Leaching test, the environmental stability was confirmed. That is, non-detection of harmful lists and dense shotcrete structure result from mixing Granulated Blast Furnace Slag. As a result of lab. and field test, Blast Furnace Slag is superior to Plain Batch in improving strength and durability. And it will be able to improve to some extent the problem caused by the delayed reaction of existing Granulated Blast Furnace Slag with alkali activated material. Also the proper amount of Granulated Blast Furnace Slag is estimated to be under 30%. Finally, it is possible that Granulated Blast Furnace Slag can apply to economical recycling and development of the Ready-mixed Shotcrete for its price is only about 5% of Silica-fume’s price.

고로슬래그시멘트를 사용한 콘크리트의 물리적 특성에 관한 실험적 연구

임명관(Lim Myung-Kwan),한다희(Han Da-Hee),김광기(Kim Kwang-Ki),박무영(Park Moo-Young),김성식(Kim Sung-Sik),정상진(Jung Sang-Jin) 대한건축학회 2007 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.27 No.1

As a part of efforts for conformity of demand to high quality of concrete and for solution of economic problem, ground granulated blast furnace slag has been utilized by means of cement replacement. With utilization of blast-furnace slag, superior performance can be ensured, environmental pollution can be prevented and economical advantage can be obtained. But blast-furnace slag has a disadvantages like retardation of strength manifestation, etc in the construction field, so properties examination of concrete using blast-furnace slag cement is necessary. So in this study there is a purpose to present a fundamental data to prove possibility of blast-furnace slag cement in construction fields. So this paper will show the data of blast-furnace slag cement that is produced from several company and compare with it.

고로슬래그 미분말을 사용한 고성능 콘크리트의 역학특성 및 내구특성에 관한 실험적 연구

이상수(Lee Sang-Soo),송하영(Song Ha-Young) 대한건축학회 2007 大韓建築學會論文集 : 構造系 Vol.23 No.11

In this study, the experiment was carried out to investigate and analyze the durability and mechanical properties of high performance concrete using blast-furnace slag powder. The main experimental variables were water/binder ratio 27.5, 31.5, 35.5(%) and replacement ratio of blast-furnace slag powder 0, 30, 50, 70(%). According to the test results, the principle conclusions are summarized as follows 1) When the replacement ratio of blast-furnace slag powder is increasing, slump flow become higher. but, high-range water reducer becomes less. generally, the more declining tendency the funneling time of type O shows, the more increasing replacement ratio of blast-furnace slag powder there is. 2) On one hand, at initial age, compressive strength is declined when replacement ratio of blast-furnace slag powder is increased; it shows same or higher values at age 28. on the other hand, when replacement ratio of blast-furnace slag powder is 70%, it shows lower level at age 28 comparing to plain concrete. also, elastic modulus generally shows similar level without the relation to replacement ratio of blast-furnace slag powder. 3) The durability of concrete using blast-furnace slag powder tends to be superior, but the carbonation of high performance concrete is no problem in this study scope in spite of depth of carbonation, as the replacement ratio increases.