Results 171 to 180 of about 6,053,575 (214)

Pozzolanic activity of silica dust

Cement and Concrete Research, 1979
Abstract Highly reactive aggregates and unusually alkali-rich cement call for special precautions in connection with concrete making in Iceland. Search in the past for efficient ways to counteract alkali-aggregate reactions is cited. High hopes are now connected with the pozzolanic use of silica fume from a ferrosilicon plant now under erection.
H. Asgeirsson, G. Gudmundsson
openaire   +1 more source

Effect of Mechanical Activation on the Pozzolanic Activity of Muscovite

Clays and Clay Minerals, 2019
AbstractIn order to provide a theoretical foundation for the utilization of tailings as supplementary cementitious materials, the pozzolanic activity of muscovite—a typical mineral phase in tailings—before and after mechanical activation was investigated.
Geng Yao, Haoyu Zang, Junxiang Wang, Peng Wu, Jun Qiu, Xianjun Lyu   +5 more
openaire   +1 more source

Effect of Milling and Acid Washing on the Pozzolanic Activity of Incinerator Sewage Sludge Ash

Cement and Concrete Composites, 2010
Incinerator sewage sludge ash (ISSA) is a problematic waste that contains significant levels of phosphates, primarily in the form of whitlockite (Ca3(PO4)2).
Shane Donatello, Mark Tyrer, C R Cheeseman   +2 more
exaly   +2 more sources

Thermal treatment and pozzolanic activity of sepiolite

Applied Clay Science, 1996
Abstract Samples of standard sepiolite were calcined at 370, 570 and 830°C corresponding to the various stages of thermal reaction detected by DTA and TG. Both the raw and calcined samples, before and after being mixed with Ca(OH) 2 in the presence of simulated cement pore solution, were studied with XRD, SEM, EPMA and chemical solubility.
He, Changling, Makovicky, Emil, Osbæck, B.   +2 more
openaire   +1 more source

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

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

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

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

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