This article is a stage of the author’s research into the impact of different factors on the hydration of mineral binders. The problem of cement activity decrease due to adsorption moisture influence during long-term storage in normal conditions (20°C and 50% RH) was examined. The influence of storage period in airtight and non-airtight conditions on the kinetics of heat evolution during hydration as well as on phase composition of Portland cement was characterized using experimental methods.

The most important characteristic of building materials and products based on cement is the strength after 28 days of hardening under normal conditions. Currently, however more and more attention is paid to development of fast-curing systems, resulting in need for analyzing the kinetics of hardening cement systems in early stages. Article presents the results of experimental researches of determination the relationship between growth strength of cement-sand mixture and amount of heat power released during hydration pure cement. And also the effectiveness of accelerating admixture for cement systems is established by comparing the heat release curve obtained for modified composition and similar curve obtained for control composition. In the course of present work it was revealed that for two cement systems differing only in presence of monofunctional accelerator it is possible to compare indirectly the growth dynamics of strength through integral heat flow curve during hydration binder and using the isothermal calorimetry. This demonstrates the possibility to simplify selection the optimal accelerating admixture in development of concrete mix and other building mixes by using methods presented in the article

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Nowadays, there is a great demand for the accelerated hardening construction mixtures. That causes the necessity to the methods development for testing the effectiveness of accelerators, well as the analysis of kinetics of cement systems hydration in the early stages of hardening. This paper presents the results of an experimental research of interrelation between the growth kinetics of cement-based binder system strength and the heat release for pure cement hydration. How it was found, two compositions of construction mix, which are identical in mineral composition and differ in the presence of mono-functional accelerator, a comparison of strength growth dynamics can be carried out indirectly via the integral curve of heat release, obtained using the method of isothermal calorimetry.

The paper presents the influence of polyethylene glycol additives wit h molecular weights of 2000... 6000 on basic physical and mechanical properties of plaster hardening at low positive and negative temperature s . The dependence of adhesion s trength to the polystyrene foam as well as compressive strength of plaster hardening at tempe rature s (+5... -10) oC on PEG molecular weight was established.