@article{Shamshygaiyn Toleubayeva_Talgat Akhmetzhanov_Gulmira Danenova_Anar Tanirbergenova_Akmaral Yeleussinova_2020, title={EFFECT OF COMPLEX ADDITIVE ON EXOTHERMIC KINETICS AND HYDRATION STAGES OF CEMENT SYSTEMS }, volume={19}, url={https://geomatejournal.com/geomate/article/view/1726}, abstractNote={<p>The influence of complex additives on the kinetics of cement exothermia and the stage of <br>cement hydration at hardening of heavy concrete in industrial conditions has been studied. It is established <br>that in heavy concrete B35 with the use of cement CEM I 42.5 N SS with complex admixture maximum <br>temperature of hydration - 79.0 ° C reaches 26 hours 30 minutes after pouring and preservation of maximum <br>temperature within 78.0-79.0 ° C continues for 9 hours. Complex additives significantly increase the degree <br>of hydration of cement. At the same time, the initial hardening time is 4-4.5 % and 28 day hardening age is <br>up to 15 %. It is established that the introduction of complex additive in the cement composition of CEM I <br>42.5 N SS promotes the formation of smaller and mostly oriented secondary crystals of Portlandite. The <br>considered complex additives consisting of the active mineral additive (wastes of enrichment of polymetallic <br>ores), nanofiller (microsilica) and chemical additives (master air 200 and master rheobuid 1000) changing <br>speed of hydration and time of achievement of the maximum temperature index, define the periods of hydrate <br>formation.</p>}, number={75}, journal={GEOMATE Journal}, author={Shamshygaiyn Toleubayeva and Talgat Akhmetzhanov and Gulmira Danenova and Anar Tanirbergenova and Akmaral Yeleussinova}, year={2020}, month={Nov.}, pages={184–190} }