Results 141 to 150 of about 2,625 (181)

The Preparation and Pozzolanic Activity of Metakaolin Admixtures

Key Engineering Materials, 2013
The optimum burning temperature of kaolinite and the optimum proportion of metakaolin (MK) in cement paste were studied by the compressive strength ratio method. Metakaolin was obtained at different burning temperature of 700°C, 750°C, 800°C and 850°C for 4 hours, and mixed into cement with the incorporation of 0, 5wt.%, 10wt.%, 15wt.% and 20wt.%.
Bao Min Wang, Yuan Zhang, Ming Li
openaire   +1 more source

Pozzolanic activity of pulverized fuel ash

Cement and Concrete Research, 1975
Abstract The pozzolanic activity of pulverized fuel ash (p.f.a.) has been determined by measuring the rate of dissolution of silica from p.f.a. in 0.1 M hydrofluoric acid. The rate of extraction of silica follows a logarithmic law and the rate constant is an index of the pozzolanic activity of the ash.
E. Raask, M.C. Bhaskar
openaire   +1 more source

Effect of iron on pozzolanic activity of kaolin

Construction and Building Materials, 2013
Abstract The effect of iron on the pozzolanic activity of kaolin is studied. For this, model kaolin is enriched by different iron contents. It has been proved that iron is deposited on kaolinitic sheets in the form of hematite (Fe2O3) or goethite (FeOOH). The clays thus obtained are treated thermally at 700 °C for 5 h.
Halima Ghorbel, Basma Samet
openaire   +1 more source

Reactivity of lime Activated Pozzolans

SP-202: Third Canmet/ACI International Symposium: Sustainable Development of Cement and Concrete, 2001
This paper utilizes electrical methods to follow the early hydration characteristics of a range of materials activated with calcium hydroxide at room temperature (20 degrees C). The electrical response is measured in terms of the in-phase (i.e. resistance) and quadrature (i.e. capacitance) components of the sample admittance.
openaire   +1 more source

Pozzolanic activity of calcined moler clay

Cement and Concrete Research, 1990
Abstract In order to investigate the possibility of using an industrial by-product of calcined Moler from the production of Moler bricks as a pozzolan in cement and concrete, a number of tests were carried out to establish the pozzolanic properties.
Stig Johansson, Per Just Andersen
openaire   +1 more source

Pozzolanic activity of various siliceous materials

Cement and Concrete Research, 2006
Abstract The accelerated pozzolanic activity of various siliceous materials, like silica fume, fly ash (as received and fine ground), quartz, precipitated silica, metakaolin and rice husk ash (RHA; various fineness and carbon content), has been determined.
openaire   +1 more source

An overview on the activation of reactivity of natural pozzolans

Canadian Journal of Civil Engineering, 2001
Natural pozzolan is one of the oldest construction materials. Lime-pozzolan cements have been used for several thousands of years and have an excellent reputation for their durability. Pozzolans are being widely used as a cement replacement in Portland cement concrete.
openaire   +1 more source

Pozzolanic Activity of Calcined Red Mud

"SP-132: Fly Ash, Silica Fume, Slag, and Natural Pozzolans and Natural Pozzolans in Concrete - Proceedings Fourth Interna", 1992
In order to investigate the possibility of using red mud by-product from the aluminum industry) as a pozzolan in the cement and concrete industries, tests were carried out to examine the pozzolanic properties of calcined red mud. It was found that the red mud had the maximum reactivity when calcined at 600 deg C, because on hydration the lime content ...
openaire   +1 more source

Monitoring pozzolanic activity by direct activation with calcium hydroxide

Construction and Building Materials, 1996
Abstract In this paper the change in conductivity of pozzolan/CH mixtures, at ambient temperatures, is monitored for periods extending over two days. Such a method allows the chemical activity within the mixture to be followed and it is shown that a number of features/parameters can be identified which are related to the pozzolanic reactivity of the ...
W.J. McCarter, D. Tran
openaire   +1 more source

Pozzolanic activity of mechanochemically and thermally activated kaolins in cement

Cement and Concrete Research, 2015
This paper reports on the mechanochemical activation by intensive grinding as an alternative way to produce pozzolanically reactive metakaolin. The physicochemical properties, pozzolanic reactivity and impact on cement hydration of mechanochemically and thermally activated kaolinitic clays were compared.
Alireza Souri, Hadi Kazemi-Kamyab, Ruben Snellings, Rahim Naghizadeh, Farhad Golestani-Fard, Karen Scrivener   +5 more
openaire   +1 more source