• 제목/요약/키워드: lightweight mortar

검색결과 70건 처리시간 0.034초

Effect of pumice powder and artificial lightweight fine aggregate on self-compacting mortar

  • Etli, Serkan;Cemalgil, Selim;Onat, Onur
    • Computers and Concrete
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    • 제27권3호
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    • pp.241-252
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    • 2021
  • An experimental program was conducted to investigate the fresh properties, mechanical properties and durability characteristics of the self-compacting mortars (SCM) produced with pumice powder and Artificial Lightweight Fine Aggregate (aLWFA). aLWFA was produced by using fly ash. A total of 16 different mixtures were designed with a constant water-binder ratio of 0.37, in which natural sands were partially replaced with aLWFA and pumice powder at different volume fractions of 5%, 10% and 15%. The artificial lightweight aggregates used in this study were manufactured through cold bonding pelletisation of 90% of class-F fly ash and 10% of Portland cement in a tilted pan with an ambient temperature and moisture content. Flowability tests were conducted on the fresh mortar mixtures beforehand, to determine the self-compacting characteristics on the basis of EFNARC. To determine the conformity of the fresh mortar characteristics with the standards, mini-slump and mini-V-funnel tests were carried out. Hardened state tests were conducted after 7, 28 and 56 days to determine the flexural strength and axial compressive strength respectively. Durability, sorptivity, permeability and density tests were conducted at the end of 28 days of curing time. The test results showed that the pumice powder replacement improved both the fresh state and the hardened state characteristics of the mortar and the optimum mixture ratio was determined as 15%, considering other studies in the literature. In the aLWFA mixtures used, the mechanical and durability characteristics of the modified compositions were very close to the control mixture. It is concluded in this study that mixtures with pumice powder replacement eliminated the negative effects of the aLWFA in the mortars and made a positive contribution.

콘크리트용 굵은 골재로서 염색공단 열원 폐재의 적용성에 관한 연구 (A Study on Application of Dyeing Industrial Heat Source Waste Aggregate as Concrete Aggregate)

  • 윤장길;김효열;임남기
    • 한국건축시공학회지
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    • 제5권1호
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    • pp.123-129
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    • 2005
  • This study is as a part of the new disposal and recycling plans of heat-resource waste of Daegu dyeing industrial center we tried to examine applicable possibility of crushed thing(waste aggregate) as aggregates for mortar and concrete. To examine applicable possibility of waste aggregate as a lightweight-aggregate for concrete and mortar, we carried this study by mainly property examination of concrete according to replacement ratio of waste aggregate. We carried slump, unit weight, compressive strength and bending strength test according to replacement ratio of waste aggregate. As the result of that, if we use waste aggregate, lightweight of concrete and mortar will be possible. Specially it shows a strength improvement effect of cement hardening according to using this so it is judged that applicable possibility as aggregate for concrete and mortar is very excellent.

열병합발전소의 열원폐자재를 골재로 활용한 콘크리트특성에 관한 연구 (The Study on Application of a Heat annexation power plant Source Waste Aggregate as Concrete Aggregate)

  • 이명효;김효열;임남기
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2005년도 춘계 학술기술논문발표대회 논문집
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    • pp.99-104
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    • 2005
  • This study is as a part of the new disposal and recycling plans of heat-resource waste of Daegu dyeing, industrial center we tried to examine applicable possibility of crushed thing(waste aggregate) as aggregates for mortar and concrete. To examine applicable possibility of waste aggregate as a lightweight-aggregate for concrete and mortar, we carried this study by mainly property examination of concrete according to replacement ratio of waste aggregate. We carried slump, unit weight, compressive strength and bending strength test according to replacement ratio of waste aggregate. As the result of that, if we use waste aggregate, lightweight of concrete and mortar will be possible. Specially it shows a strength improvement effect of cement hardening according to using this so it is judged that applicable possibility as aggregate for concrete and mortar is very excellent.

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건식공정 바텀애시 경량 잔골재의 입도 조건에 따른 모르타르의 특성 (Properties of Mortar Using Lightweight Fine Aggregate Made by Bottom Ash Discharged Air Cooling Process according to Grading)

  • 최홍범;선정수;유재성;이무;최덕진;김진만
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2014년도 추계 학술논문 발표대회
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    • pp.53-54
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    • 2014
  • This study evaluates engineering properties of mortar using lightweight fine aggregate made by bottom ash discharged air cooling process according to grading. Then we confirm possibility of use as lightweight fine aggregate. Consequently, Mix using bottom ash need additional examination for a change with the passage of time of flow. Also, mix of S indicates similar compressive strength with mix of Plain and 16% decrease of unit weight compared to mix of Plain; while mix of B indicates 10% decrease of compressive strength and 16% decrease of unit weight. Therefore, this study shows that mix of S and B is superior compared with other mix.

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회수수를 사용한 3성분계 경량 골재 모르타르의 공학적 특성에 관한 실험적 연구 (An Experimental Study on the Engineering Characteristics of Ternary Lightweight aggregate Mortar Using Recycling Water)

  • 이재인;배성호;김지환;최세진
    • 한국건설순환자원학회논문집
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    • 제10권1호
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    • pp.48-55
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    • 2022
  • 본 연구는 콘크리트의 운반 과정 중 발생하는 레미콘 회수수의 재활용율 증대 및 온실가스 저감을 위한 연구의 일환으로 회수수를 배합수 및 인공경량골재 프리웨팅수로 사용하고 고로슬래그 미분말 및 플라이애시를 시멘트 대체재로 사용한 3성분계 경량 골재 모르타르의 공학적 특성을 검토하였다. 이를 위해 3성분계 경량 골재 모르타르의 플로우, 기건단위질량, 압축강도, 건조수축, 중성화 깊이, 염화물 이온 침투 저항성을 측정하였으며 측정 결과 회수수를 사용할 경우 높아진 알칼리도에 의해 시멘트계 재료들의 반응성이 높아졌으며 3성분계 배합과 함께 사용할 경우 고로슬래그 미분말 15 %, 플라이애시를 5 % 사용할 시 모르타르의 압축강도 및 내구특성 향상에 긍정적인 것으로 나타났다.

경량기포 콘크리트를 이용한 석재패널 부착 고강도 RC 기둥의 내화 및 폭렬특성 (Properties of the Spalling and Fire Resistance on the High Strength RC Column attached with the Stone Panel Using Lightweight Foamed Concrete)

  • 이동규;백대현;김원기;조용백;한민철;한천구
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2007년도 추계 학술논문 발표대회
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    • pp.19-22
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    • 2007
  • This study discussed the prevention of the spalling and improvement of the fire resistance performance how to fill up lightweight foamed concrete on high strength RC column attached with the stone panel. The destructive spalling extremely occur caused by sudden high temperature and increased vapor pressure corresponding to falling the ston panel at all RC column, and the steel bar is exposed. The stone panel fall off about 30 minutes and spalling occur about 70 minutes on Plan RC column, fire endurance paint, and fire endurance mortar, so it can be confirmed that fire endurance paint and mortar, which is used as fire endurance material, are not effective. In the other side, it can be protected from fire about $120{\sim}140$ minutes when the lightweight foamed concrete is used as fire endurance material. For the weight loss after the fire test, plain is 33, fire endurance paint is 37%, and fire endurance mortar s 40.7%. And W/B 60%-3 is 53.4%, 60%-1.5 is 40.1%,65%-3 is 39.4%, and 65%-1.5% is 47.1. Overall, the weight loss of the plain is lower than that of the lightweight foamed concrete.

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Using generalized regression neural network (GRNN) for mechanical strength prediction of lightweight mortar

  • Razavi, S.V.;Jumaat, M.Z.;Ahmed H., E.S.;Mohammadi, P.
    • Computers and Concrete
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    • 제10권4호
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    • pp.379-390
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    • 2012
  • In this paper, the mechanical strength of different lightweight mortars made with 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95 and 100 percentage of scoria instead of sand and 0.55 water-cement ratio and 350 $kg/m^3$ cement content is investigated. The experimental result showed 7.9%, 16.7% and 49% decrease in compressive strength, tensile strength and mortar density, respectively, by using 100% scoria instead of sand in the mortar. The normalized compressive and tensile strength data are applied for artificial neural network (ANN) generation using generalized regression neural network (GRNN). Totally, 90 experimental data were selected randomly and applied to find the best network with minimum mean square error (MSE) and maximum correlation of determination. The created GRNN with 2 input layers, 2 output layers and a network spread of 0.1 had minimum MSE close to 0 and maximum correlation of determination close to 1.

고로슬래그미분말 혼입율에 따른 회수수 사용 경량모르타르의 유동성 및 강도특성 (The Fluidity and Comprssive Strength Properties of Lightweight Mortar Using Recycling Water according to Blast Furnace Slag Powder Ratio)

  • 배성호;이재인;김지환;오태규;최세진
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2020년도 봄 학술논문 발표대회
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    • pp.136-137
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    • 2020
  • This study compared and analyzed the fluidity and strength characteristics of mortar using the recycling water, indicates strong alkali properties, as pre-wetting water of artificial light aggregate to increase usage ratio of recycling.

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Experimental investigation on steel-concrete bond in lightweight and normal weight concrete

  • Chen, How-Ji;Huang, Chung-Ho;Kao, Zhang-Yu
    • Structural Engineering and Mechanics
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    • 제17권2호
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    • pp.141-152
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    • 2004
  • The bonding behaviors of Lightweight Aggregate Concrete (LWAC) and normal weight concrete were investigated experimentally. Pull-out tests were carried out to measure the bond strengths of three groups of specimens with compressive strength levels of 60, 40, and 20 MPa, respectively. Test results showed that the difference in the bond failure pattern between LWAC and normal weight concrete was significant as the concrete compressive strength became lower than 40 MPa. The corresponding bond strengths of LWAC were lower than that for normal weight concrete. As the compressive strength of concrete became relatively high (> 40 MPa), a bond failure pattern in normal weight concrete occurred that was similar to that in LWAC. The bond strength of LWAC is higher than that for normal weight concrete because it possesses higher mortar strength. Stirrup use leads to an increase of approximately 20% in nominal bond strength for both types of concrete at any strength level.

괴상석탄재와 폐주물사를 혼입한 경량모르터의 특성에 관한 기초적 연구 (A Fundamental Study on the Properties of Lightweight Mortar Mixed with Bottom ash and Waste Foundry Sand)

  • 이승한;한형섭;정용욱
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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    • pp.223-228
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    • 1997
  • In this study, bottom ash, lightweight aggregate, and Expanded Polystyrene was used to lighten the mortar. In order to compensate the reduction of strength caused by lightening, the waste foundry sand produced as solid waste was substituted for fine aggregate. As the device of reducing the ratio of absorption, the procedure of mixture was altered to check the effectiveness of surface coating of porous lightweight aggregate. It was observed over 170kg/$\textrm{cm}^2$ compressive strength at gravity about 1.3, an over 380kg/$\textrm{cm}^2$ at gravity about 1.7. the maximum strength was occurred when 30% of fine aggregate was replaced was replaced with waste foundry sand, and the ratio of absorption was decreased over 10% by changing the procedure of mixture.

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