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The influence of calcium nitrate on the plasticizing effect of cement paste

    Gintautas Skripkiūnas Affiliation
    ; Asta Kičaitė Affiliation
    ; Mindaugas Macijauskas Affiliation

Abstract

The rheological properties of the cement pastes have been determined using a rotational viscometer under a special testing routine by increasing and retaining a steady rotation speed of the viscometer cylinder up to certain values and for a certain time. These tests, using rotational viscometer, have been conducted by making the assessment of ce­ment paste flow curves, using Bingham rheological model. Rheological properties of cement pastes were tested at dif­ferent times after pastes mixing: 0 min, 30 min, 60 min, 90 min, 120 min and 180 min. Cement pastes with same W/C ratio equal to 0.35 were tested. The content of admixture was used 0%, 0.5%, 1%, 2%, 3% and 5%. The admixture of Ca(NO3)2 can be used in cement pastes and concretes without a reduction in consistency during 120 min in the dosage of up to 2%. Dosages of Ca(NO3)2 from 3% are not recommended for cement pastes and concrete, they significantly increase the viscosity of mixtures immediately after mixing The admixture of calcium nitrate changes thixotropy of ce­ment pastes. In this case, a bigger dosage of calcium nitrate increases the thixotropy of pastes.

Keyword : cement pastes, calcium nitrate, admixture, shear stress, viscosity, thixotropy

How to Cite
Skripkiūnas, G., Kičaitė, A., & Macijauskas, M. (2016). The influence of calcium nitrate on the plasticizing effect of cement paste. Journal of Civil Engineering and Management, 22(3), 434-441. https://doi.org/10.3846/13923730.2015.1120771
Published in Issue
Mar 24, 2016
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