• Title/Summary/Keyword: Limestone powder

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Evaluation of Engineering Characteristics and Utilization of Nonmetal Mining Waste Powder as Geo-Materials (비금속 광산 폐분의 공학적 특성 및 활용 가능성 분석)

  • Cho, Jinwoo;Lee, Yongsoo
    • Journal of the Korean GEO-environmental Society
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    • v.12 no.12
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    • pp.71-78
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    • 2011
  • This paper aims to present the evaluation of engineering characteristics and reusing possibility of waste powders produced in dolomite and limestone nonmetal mining by physical and mechanical experiments on compaction, uniaxial compressive strength, permeability, chemical composition, and so on. Granite soil, 2 types of limestone waste powder, and 1 type of dolomite waste powder were used for main materials, and cement and bentonite were used for admixed materials in this experiments. The findings based on the experimental results are the severe difference of chemical composition of the dolomite & limestone waste powder and the crushed rock waste powder, and the outstanding of engineering characteristics of the dolomite waste powder with high content of MgO compared with the limestone waste powder. The engineering properties on compaction, uniaxial compressive strength, and permeability are enhanced with increase of admixed ratio of waste powder on granite soil. From the experimental results, it can be suggested that the dolomite waste powder admixed with in-situ granite soil is useful as geo-materials with considering of distribution costs.

Effect of Limestone Powder on Hydration of C3A-CaSO4·2H2O System (C3A-CaSO4·2H2O 계의 수화반응에 미치는 석회석 미분말의 영향)

  • Lee, Jong-Kyu;Chu, Yong-Sik;Song, Hun
    • Journal of the Korean Ceramic Society
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    • v.48 no.6
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    • pp.584-588
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    • 2011
  • In this work, effects of limestone powder on hydration of $C_3A-CaSO_4{\cdot}2H_2O$ system was discussed based on the XRD Quantitative analysis, and the possibility of Delayed Ettringite Formation was also discussed. The early hydration of $C_3A$ was delayed by addition of $CaCO_3$ powder. The delay effect was enhanced by increasing of $CaCO_3$ content and finer powder of $CaCO_3$ addition. After consumption of $CaSO_4{\cdot}2H_2O$, the reaction of $CaCO_3$ is started. Delayed Ettringite Formation would take place because monosulfoaluminate is not stable in presence of $CaCO_3$. In order to prevent the delayed ettringite formation in $C_3A-CaSO_4{\cdot}2H_2O-CaCO_3$ system, the reduction of monosulfoaluminate formation is important. Therefore, by increasing the amount of $CaCO_3$ addition and finer $CaCO_3$ powder addition, the delayed ettringite formation can be prevented.

The Effect of Addition of Blast-furnace Slag Powder and Limestone powder on Shotcrete Binder with Calcium Aluminate Accelerator (고로슬래그 분말 및 석회석 분말이 시멘트 광물계 급결제를 사용한 숏크리트 결합재 물성에 미치는 영향)

  • Kang, ong-Hee;Kim, Gyu-Yong;Choi, Jae-Won;Koo, Kyung-Mo;Hwang, Bong-Choon
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.24 no.2
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    • pp.86-93
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    • 2020
  • Shotcrete concrete is generally used in the form of ready-mixed concrete products using type I ordinary portland cement(hereinafter referred to as OPC) and about 5% of accelerator mixed separately in the field. In this study, we tested the effect of addition of slag powder(SP) and limestone powder(LSP) on a penetration resistance, compressive strength of binder for shotcrete using calcium aluminate type accerlerator. And we analysed hydrates and pore structure effects on mortar performance. In the future, it is expected to be useful for manufacturing optimized composite cement as a binder for shotcrete.

Effect of Limestone Powder on Hydration of $C_{3}A-CaSO_{4}$ $\cdot$ $2H_{2}O$ system ($C_3A-CaSO_4\cdot2H_2O$ 계의 수화반응에 미치는 석회석미분말의 영향)

  • Lee Jong-Kyu;Chu Yong-Sik
    • Proceedings of the Korea Concrete Institute Conference
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    • 2005.05b
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    • pp.349-352
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    • 2005
  • In this work, effects of limestone powder on hydration of $C_3A-CaSO_4\cdot2H_2O$ system was discussed based on the XRD Quantitative analysis, and the possibility of Delayed Ettringite Formation was also discussed. The early hydration of $C_{3}A$ was delayed by addition of $CaCO_{3}$ powder. The delay effect was enhanced by increasing of $CaCO_{3}$ content and finer powder of $CaCO_{3}$ addition. After consumption of $CaSO_4\cdot2H_2O$, the reaction of $CaCO_{3}$ is started. Delayed Ettringite Formation would take place because monosulfoaluminate is not stable in presence of $CaCO_{3}$. In order to prevent the delayed ettringite formation in $C_3A-CaSO_4\cdot2H_2O-CaCo_3$ system, the reduction of monosulfoaluminate formation is important. Therefore, by increasing the amount of $CaCO_{3}$ addition and finer $CaCO_{3}$ powder addition, the delayed ettringite formation can be prevented.

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Effects of Limestone Powder and Silica Fume on the Hydration and Pozzolanic Reaction of High-Strength High-Volume GGBFS Blended Cement Mortars (고강도 고함량 고로슬래그 혼합 시멘트 모르터의 수화 및 포졸란 반응에 미치는 석회석 미분말과 실리카퓸의 영향)

  • Jeong, Ji-Yong;Jang, Seung-Yup;Choi, Young-Cheol;Jung, Sang-Hwa;Kim, Sung-Il
    • Journal of the Korea Concrete Institute
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    • v.27 no.2
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    • pp.127-136
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    • 2015
  • To evaluate the effects of limestone powder and silica fume on the properties of high-strength high-volume ground granulated blast-furnace slag (GGBFS) blended cement concrete, this study investigated the rheology, strength development, hydration and pozzolanic reaction characteristics, porosity and pore size distribution of high-strength mortars with the water-to-binder ratio of 20, 50 to 80% GGBFS, up to 20% limestone powder, and up to 10% silica fume. According to test results, compared with the Portland cement mixture, the high-volume GGBFS mixture had much higher flow due to the low surface friction of GGBFS particles and higher strength in the early age due to the accelerated cement hydration by increase of free water; however, because of too low water-to-binder ratio and cement content, and lack of calcium hydroxide content, the pozzolanic reactio cannot be activated and the long-term strength development was limited. Limestone powder did not affect the flowability, and also accelerate the early cement hydration. However, because its effect on the acceleration of cement hydration is not greater than that of GGBFS, and it does not have hydraulic reactivity unlikely to GGBFS, compressive strength was reduced proportional to the replacement ratio of limestone powder. Also, silica fume and very fine GGBFS lowered flow and strength by absorbing more free water required for cement hydration. Capillary porosities of GGBFS blended mortars were smaller than that of OPC mortar, but the effect of limestone powder on porosity was not noticeable, and silica fume increased porosity due to low degree of hydration. Nevertheless, it is confirmed that the addition of GGBFS and silica fume increases fine pores.

Current Status of Lime Bordeaux Mixture Research using Properties of Lime based Minerals (석회계 광물 특성을 활용한 석회보르도액 연구 현황)

  • Kim, Young-Jin;Seo, Jun-Hyung;Kim, Yang-Soo;Cho, Kye-Hong;Cho, Jin-Sang
    • Resources Recycling
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    • v.31 no.3
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    • pp.16-26
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    • 2022
  • Limestone is the largest mineral resource in South Korea and is used in various industries, particularly as a primary raw material in the cement and iron industries. However, research on the utilization of limestone in fields such as agriculture, powder, and green chemistry is severely lacking. In this review, studies concerning the crop antibacterial industry using unslaked or slaked lime produced from limestone were analyzed. Reports regarding lime bordeaux mixture were also considered. By compiling research results, processing technologies for improving the antibacterial efficiency of lime bordeaux mixture are discussed. In addition, plans for the revitalization of research on crop antibacterial agents through the limestone processing industry were summarized.

Effect of Fineness and SO3 Content of Limestone Mixed Cement on Mortar (석회석 혼합시멘트의 분말도 및 SO3 함량이 시멘트 모르타르에 미치는 영향)

  • In, Byung-Eun;Kim, Jin-Sung;Nam, Seong-Young;Kim, Chun-Sik;Cho, Sung-Hyun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2023.05a
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    • pp.105-106
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    • 2023
  • Using the limestone powder as material that can alternate the clinker, it seems to get positive effect as filler and enhance workability of cement, but the amount of replacement can affect compressive strength of cement. This study was evaluated the effect of limestone mixed cement fineness and SO3 content on cement mortar. As a result of measuring the compressive strength, it showed 93% compared to the compressive strength of Plain 28 days at fineness 4,400 and SO3 2.6%. It is judged that additional research is necessary to express the strength equivalent to that of Plain.

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A Study on the Quality Properties of Exposed High Fluidity Concrete using Fly Ash and Limestone Powder (플라이애시 및 석회석 미분말을 사용한 고유동 노출 콘크리트의 품질특성에 관한 연구)

  • Choi, Yun-Wang;Oh, Sung-Rok;Kim, Ji-Hoon;Kim, Kyung-Hwan
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.1 no.1
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    • pp.67-75
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    • 2013
  • Recently, the interest is increasing about the exposed concrete, accordingly, exposed concrete is expanding the use. However, concrete structures is difficult to apply the general concrete for exposed concrete, due to complex section and compact reinforcement, increasingly. Therefore, in this paper, for application of high fluidity concrete as exposed concrete, exposed high fluidity concrete using fly ash and lime stone powder was manufactured and observed quality property(fluidity properties, mechanical properties and Surface Properties) of exposed high fluidity concrete. The experiments are based on the OPC and LSP10, was evaluated Impact on the quality of concrete according to mixing ratio of FA(0, 10, 15 and 20). As a result, fluidity properties, mechanical properties and Surface Properties of exposed high fluidity concrete were satisfied to requirement conditions, fluidity and surface finishability was improved depending on mix of fly ash and limestone powder. Through this, we utilize of basic research data for development of high fluidity concrete for exposed concrete.

Mechanical behavior of HPFRCC using limestone calcined clay cement (LC3) and oxygen plasma treated PP fibers

  • Sajjad Mirzamohammadi;Masoud Soltani
    • Structural Engineering and Mechanics
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    • v.89 no.4
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    • pp.349-362
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    • 2024
  • High-performance fiber-reinforced cement composites (HPFRCC) are new materials created and used to repair, strengthen, and improve the performance of different structural parts. When exposed to tensile tension, these materials show acceptable strain-hardening. All of the countries of the globe currently seem to have a need for these building materials. This study aims to create a low-carbon HPFRCC (high ductility) that is made from materials that are readily available locally which has the right mechanical qualities, especially an increase in tensile strain capacity and environmental compatibility. In order to do this, the effects of fiber volume percent (0%, 0.5%, 1%, and 2%), and determining the appropriate level, filler type (limestone powder and silica sand), cement type (ordinary Portland cement, and limestone calcined clay cement or LC3), matrix hardness, and fiber type (ordinary and oxygen plasma treated polypropylene fiber) were explored. Fibers were subjected to oxygen plasma treatment at several powers and periods (50 W and 200 W, 30, 120, and 300 seconds). The influence of the above listed factors on the samples' three-point bending and direct tensile strength test results has been examined. The results showed that replacing ordinary Portland cement (OPC) with limestone calcined clay cement (LC3) in mixtures reduces the compressive strength, and increases the tensile strain capacity of the samples. Furthermore, using oxygen plasma treatment method (power 200 W and time 300 seconds) enhances the bonding of fibers with the matrix surface; thus, the tensile strain capacity of samples increased on average up to 70%.