• 제목/요약/키워드: Cement free

검색결과 210건 처리시간 0.024초

Formulation design of chloride-free cement additive by response surface methodology

  • Zhu, Zi-chen;Gu, Ding-cheng
    • Advances in Computational Design
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    • 제1권1호
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    • pp.27-35
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    • 2016
  • The influences of chloride-free components of the cement additive: triethanolamine, triisopropanolamine, sodium hyposulfite and calcium gluconate on the 1d, 3d and 28d compressive strength of cement were investigated by response surface methodology. It found the early strength activators, triethanolamine and sodium hyposulfite could enhance the 1d strength of cement effectively but they did not contribute to the 3d strength enhancement, and further their interaction was able to decrease the 28d strength of cement. Calcium gluconate was not that effective for the strength enhancement on 3 and 28 days when it's simply dosed. However the interaction effect of calcium gluconate with triisopropanolamine could strongly favor the strength enhancement of cement after 3 days. Results indicated it was necessary to focus attention on the potential interactions among the chemical components. And for the concern of four chemicals studied in this paper, it was feasible to formulated a kind of chloride-free cement additive that can be effective for the early strength of cement and its the strength after 3 days.

고로 슬래그 시멘트 페이스트 내 자유염화물량과 물가용성 염화물량 평가에 관한 연구 (A Study on the Evaluation of the Water-soluble Chloride Content and Free-chloride Content in Blast Furnace Slag Cement Pastes)

  • 조영국;소승영
    • 한국건축시공학회지
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    • 제4권4호
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    • pp.95-101
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    • 2004
  • The purpose of this paper is to compare free-chloride content with water-soluble chloride in blast furnace cement(BSC) paste. The content of free-chloride in cement paste measured by pore solution analysis and water-soluble chloride measured by ASTM. The result of this study are as follows: 1. The concentration of chloride ion in pore solution of BSC-solidified matrix is almost as low as 43-71% compared to that of OPC-solidified matrix containing the same chloride content in cement paste. 2. The binding capacity of specimens, OPC Pl-P5, are 93.5-77%, but the binding capacity of specimens, BSC Pl-P5 are 97.1-86.1%, which is to be as high as 2-9.1% compared to OPC containing the same chloride content. 3. In terms of water-soluble chloride content in BSC paste are 15-31.7 percent of chloride addition but free-chloride content in pore solution are 2.9-13.9 percent of chloride addition. The free-chloride content in pore solution is 19.3-43.8 percent lower for the water-soluble chloride content in cement paste.

양생조건에 따른 경화제 무첨가 에폭시수지 혼입 PMM의 경화특성 (Hardening Properties of Hardener-Free Epoxy-Modified Mortars by Curing Conditions)

  • 이재화;김주영;김완기
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2012년도 추계 학술논문 발표대회
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    • pp.255-257
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    • 2012
  • Epoxy resin without any hardener can harden in the presence of hydroxide ions in cement mortars and concretes at ambient temperature. The purpose of present study is to examine the hardening properties of hardener-free epoxy-modified mortars by curing conditions. The hardener-free epoxy-modified mortars using diglycidyl ether of A epoxy resin are prepared with various polymer-cement ratios, and subjected to initial moist/dry curing, initial steam(90℃) curing, initial steam/heat(80℃, 100℃) curing.As a result, degree of hardening of epoxy resin in initial moist/dry cured, initial steam cured and initial steam/heat(80℃) cured hardener-free epoxy-modified mortars is decreased with increasing polymer-cement ratio. However, it is markedly improved with additional dry-curing periods. On the other hand, regardless of the polymer-cement ratio and dry curing periods, degree of hardening of hardener-free epoxy-modified mortars with initial steam/heat(100℃) cure is over 95%.

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레드머드 대체율에 따른 폴리머 혼입 알칼리활성화 슬래그-레드머드 시멘트모르타르의 강도 및 기공특성 (Strength and Pore Characteristics of Alkali-activated Slag-Red Mud Cement Mortar used Polymer According to Red Mud Content)

  • 권성준;강석표
    • 한국구조물진단유지관리공학회 논문집
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    • 제20권2호
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    • pp.26-33
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    • 2016
  • 알칼리활성화 슬래그-레드머드 시멘트는 알칼리활성화 시멘트 연구의 일환으로서 시멘트 조성에서 알칼리자극제, 고로슬래그와 레드머드로 구성되어져 있으며, 포틀랜트 시멘트를 사용하지 않는 클링커 프리 시멘트(Clinker Free Cement)를 의미한다. 본 논문에서는 포틀랜트 시멘트를 전혀 사용하지 않고 고분자 유기화합물인 재유화형 분말 폴리머를 혼입한 알칼리활성화 슬래그 시멘트에 레드머드의 대체율을 달리하여 강도특성, 기공특성 등을 기존 포틀랜트 시멘트와 비교 평가하였다. 그 결과 알칼리활성화 시멘트에 레드머드를 대체할 경우 C-S-H 광물상과 에트린가이트가 주요 수화생성물로 포틀랜트 시멘트와 비교하여 조직이 치밀하고 대체율 10%까지는 압축강도 및 휨강도가 증가하였다.