Heat of hydration of Portland Cement–Metakaolin–Fly ash (PC–MK–PFA) blends

The effects of different cementing systems on the expansion of mortars containing iron sulphide-bearing aggregate was studied. Using a recently developed oxidation mortar bar test, the results showed that cementing systems containing low-calcium fly ash, metakaolin, slag, high-sulphate resisting Portland cement, or low heat of hydration Portland cement could reduce the expansion by 50–85%. The main suggested mechanisms behind the reduced expansion is the more refined pore structure of samples with SCMs, and the reduced C3A of low heat of hydration Portland cement. The refined pore structure reduces the permeation of the oxidizing solution into the samples. The similarity of this to penetration of oxygen into concrete under field exposure needs to be determined. Soaking the samples for >3 h in the oxidizing agent can produce excessive expansion – not related to oxidation of iron sulphide phases – in samples with cementing blends containing reactive alumina such as metakaolin.

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Retardation Effects in the Hydration of Cement-Fly Ash Pastes

MRS Proceedings ◽

10.1557/proc-43-65 ◽

1984 ◽

Vol 43 ◽

Cited By ~ 1

Author(s):

Michael W. Grutzeck ◽

Wei Fajun ◽

Della M. Roy

Keyword(s):

Fly Ash ◽

Portland Cement ◽

Solid Phase ◽

Heat Of Hydration ◽

Type I ◽

Fly Ashes ◽

Solution Composition ◽

Early Hydration ◽

High Calcium ◽

Phase Characterization

AbstractThe hydration of high-calcium and low-calcium fly ash-cementmixtures was investigated to determine the effect of fly ash upon the hydration of a Type I portland cement, and to determine the associated mechanisms of hydration. When blended with portland cement, both fly ashes retarded the early hydration process, the high-Ca more so than the low-Ca. Analyses of solution compositions and calorimetric (heat of hydration) measurements were made. The retardation and hydration effects are discussed in terms of solution composition data and solid phase characterization. The hydration effects were interpreted and compared with the results of previous work.

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Numerical Simulation of Autogenous Shrinkage of Eco-Friendly Blended Portland Cements Using a Multi-Component Hydration Model

Materials Science Forum ◽

10.4028/www.scientific.net/msf.569.261 ◽

2008 ◽

Vol 569 ◽

pp. 261-264 ◽

Cited By ~ 3

Author(s):

Xiao Yong Wang ◽

Han Seung Lee ◽

Seung Min Lim

Keyword(s):

Fly Ash ◽

Portland Cement ◽

Ordinary Portland Cement ◽

Autogenous Shrinkage ◽

Heat Of Hydration ◽

Curing Temperature ◽

Portland Cements ◽

Influence Of Water ◽

Hydration Model ◽

Numerical Program

Fly ash and granulated blast-furnace slag, which are used as blends of Portland cement, are waste materials produced in electric and energy industry. Due to excellent durability, low heat of hydration, energy-saving, resource-conserving, and generally less expensive than ordinary Portland cement, blends Portland cements is used increasingly in construction industry. Both ecology benefit and economic benefit can be achieved by using blended Portland cement. Addition of blended components to cement, especially such as fly ash or silica fume, will lead to a densification of the microstructure. The autogenous shrinkage deformation will increase and the following autogenous shrinkage crack will do harm to durability of concrete structure. In this paper, based on the multi-component hydration model, a numerical program is built to predict autogenous shrinkage of ordinary Portland cement and blended Portland cement. The numerical program considers the influence of water to cement ratio, curing temperature, particle size distribution, cement mineral components on hydration process and autogenous shrinkage. The prediction result agrees well with experiment result.

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Undissolved Ilmenite Mud from TiO2 Production—Waste or a Valuable Addition to Portland Cement Composites?

Materials ◽

10.3390/ma13163555 ◽

2020 ◽

Vol 13 (16) ◽

pp. 3555 ◽

Cited By ~ 1

Author(s):

Filip Chyliński ◽

Jan Bobrowicz ◽

Paweł Łukowski

Keyword(s):

Fly Ash ◽

Portland Cement ◽

Silica Fume ◽

High Reactivity ◽

Heat Of Hydration ◽

Pozzolanic Activity ◽

Cement Composites ◽

Level Of Activity ◽

Natural Pozzolana ◽

Thermal Analysis Techniques

This paper presents a method of utilising ilmenite MUD created during the production of titanium dioxide (TiO2) according to the sulphate method as an additive for Portland cement composites. After the production process, undissolved MUD was additionally rinsed with water and filtrated in the factory to make it more useful (R-MUD) for implementation and also to turn back some of the by-products of the production of TiO2. R-MUD is less hazardous waste than MUD. It has a lower concentration of sulphuric acid and some heavy metals. The rinsing process raised the concentration of SiO2, which is a valuable part of R-MUD because of its potential pozzolanic activity. This means that the R-MUD might be a reactive substitute of part of Portland cement in building composites. The article presents the results of research on the pozzolanic activity of R-MUD and other materials with proved pozzolanic activity, such as silica fume, fly ash and natural pozzolana (trass). Tests were performed using thermal analysis techniques. The tests showed that the pozzolanic activity or R-MUD after three days is at the same level as silica fume and after 28 days it is twice as high as the activity of fly ash. Beyond the 180th day of curing, R-MUD had the same level of activity as fly ash. The summary is supplemented by calorimetric tests, which confirm the high reactivity of R-MUD compared to other commonly used concrete additives, already in the initial hydration period. In summary, heat of hydration after 72 h of Portland cement with R-MUD is at the same level as the heat of hydration of Portland cement with silica fume and also pure Portland cement grout. The results confirm that the process of formation of micro-silica contained in R-MUD react with calcium hydroxide to form the C-S-H phase, which is responsible for the microstructure of cement composites.

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Effect of Large Amount of Fly Ash on Hydration Process of Portland Cement at the Early Stage

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.233-235.2305 ◽

2011 ◽

Vol 233-235 ◽

pp. 2305-2309 ◽

Cited By ~ 1

Author(s):

Qing Jun Ding ◽

Ji Yu Han ◽

Xiu Lin Huang

Keyword(s):

Fly Ash ◽

Portland Cement ◽

Early Stage ◽

Ash Content ◽

Heat Of Hydration ◽

Hydration Process ◽

Hardening Mechanism ◽

Research Outcomes ◽

Binder Ratio ◽

Water To Binder Ratio

In this article, through the measurements on neat cement paste strength and heat of hydration at the early stage and using several analytical methods including XRD and SEM, effect of large amount of fly ash on the hydration process and cement's hardening mechanism of portland cement was studied when water to binder ratio is 0.35 and fly ash content is between 20% and 50%.The research outcomes find that the pozzolanic activities of fly ash are not good at the early stage.The more the content of fly ash was, the bigger the effect on strength would be.

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The Application of a New Oxidation Mortar Bar Test to Mixtures containing Different Cementing Systems

10.32920/16732804.v1 ◽

2021 ◽

Author(s):

Bassili Guirguis ◽

Medhat Shehata ◽

Josée Duchesne ◽

Benoît Fournier ◽

Benoît Durand ◽

...

Keyword(s):

Fly Ash ◽

Portland Cement ◽

Pore Structure ◽

Heat Of Hydration ◽

Iron Sulphide ◽

Oxidizing Agent ◽

Field Exposure ◽

Bar Test ◽

Reactive Alumina ◽

Mortar Bar

The effects of different cementing systems on the expansion of mortars containing iron sulphide-bearing aggregate was studied. Using a recently developed oxidation mortar bar test, the results showed that cementing systems containing low-calcium fly ash, metakaolin, slag, high-sulphate resisting Portland cement, or low heat of hydration Portland cement could reduce the expansion by 50–85%. The main suggested mechanisms behind the reduced expansion is the more refined pore structure of samples with SCMs, and the reduced C3A of low heat of hydration Portland cement. The refined pore structure reduces the permeation of the oxidizing solution into the samples. The similarity of this to penetration of oxygen into concrete under field exposure needs to be determined. Soaking the samples for >3 h in the oxidizing agent can produce excessive expansion – not related to oxidation of iron sulphide phases – in samples with cementing blends containing reactive alumina such as metakaolin.

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Effect of silica fume and fly ash on heat of hydration of Portland cement

Cement and Concrete Research ◽

10.1016/s0008-8846(02)00742-1 ◽

2002 ◽

Vol 32 (7) ◽

pp. 1045-1051 ◽

Cited By ~ 213

Author(s):

B.W. Langan ◽

K. Weng ◽

M.A. Ward

Keyword(s):

Fly Ash ◽

Portland Cement ◽

Silica Fume ◽

Heat Of Hydration

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The Application of a New Oxidation Mortar Bar Test to Mixtures containing Different Cementing Systems

10.32920/16732804.v2 ◽

2021 ◽

Author(s):

Bassili Guirguis ◽

Medhat Shehata ◽

Josée Duchesne ◽

Benoît Fournier ◽

Benoît Durand ◽

...

Keyword(s):

Fly Ash ◽

Portland Cement ◽

Pore Structure ◽

Heat Of Hydration ◽

Iron Sulphide ◽

Oxidizing Agent ◽

Field Exposure ◽

Bar Test ◽

Reactive Alumina ◽

Mortar Bar

The effects of different cementing systems on the expansion of mortars containing iron sulphide-bearing aggregate was studied. Using a recently developed oxidation mortar bar test, the results showed that cementing systems containing low-calcium fly ash, metakaolin, slag, high-sulphate resisting Portland cement, or low heat of hydration Portland cement could reduce the expansion by 50–85%. The main suggested mechanisms behind the reduced expansion is the more refined pore structure of samples with SCMs, and the reduced C3A of low heat of hydration Portland cement. The refined pore structure reduces the permeation of the oxidizing solution into the samples. The similarity of this to penetration of oxygen into concrete under field exposure needs to be determined. Soaking the samples for >3 h in the oxidizing agent can produce excessive expansion – not related to oxidation of iron sulphide phases – in samples with cementing blends containing reactive alumina such as metakaolin.

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