ENERGY SAVING FACTORS IN WINTER CONCRETING

This article considers energy-saving technologies for winter concreting of building structures and constructions. Various authors have studied mathematical models of the thermal regime of a three-dimensional building structure. The mathematical model of the heat balance equations in the concrete structure, the thermal conductivity coefficient, the dependences of the heat balance equations in the concrete structure and the junction, the thermal conductivity coefficient, the volumetric thermal conductivity, respectively, in the erected fragment and the previously erected part of the wall was implemented on a computer. The article considers the processes of cement and concrete strength gain during early freezing of concrete. In previous studies by various authors, it was found that with an increase in the time for gaining critical strength, the cost of electricity is reduced by 25-50%, due to the use of thermal inertia of the structure. The rate of cooling of monolithic structures at negative temperatures is revealed. The chemistry of cement hardening processes during early freezing is shown. Thermodynamic calculations set the limits of negative temperatures at which concrete strength curing stops, but under the action of repeated positive temperatures, the cement hydration process resumes and concrete continues to harden. The aluminum minerals of Portland cement clinker are usually the first to hydrate when the cement hardens with water, and in the presence of gypsum they form calcium hydrosulfoaluminate. This connection is very fragile and is destroyed by mechanical stress (repeated vibration) and over time even at normal temperatures. The article reviews the foreign experience of winter concreting and the preferred methods of work in this case.

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