Concrete - samogrev

But concrete is preparing another puzzle: sometimes he is able to heat itself! What is required to concrete this amazing property? It turns out that cement. In the chemical interaction of cement with water, such reactions occur, resulting in a significant amount of heat is released.Temperature increase in the formation of concrete depends on the type and amount of cement in the concrete mix. The greatest amount of heat hardening concrete distinguishes aluminous cement, minimum - shlakoportlandtstsement. And if a lot of concrete and its surface is low, the concrete is heated by this heat. Since concrete is "samogrevom"! Sometimes this heat is so much that the concrete can overheat, it will dry out before solidifying.

Concrete - "samogrev" can be used for winter concreting. So when building a massive concrete structure, then in winter the water is not heated and aggregates and concrete is not wrapped. Him, and so it will be hot! But...

NOT AFRAID OR CONCRETE heat?

What if the thermometer shows above 35є C? As this temperature will affect the curing of concrete? It turned out, the concrete is very afraid of the heat, as the high temperature of the water is evaporated and the concrete stops hardening cement. As a result, in the concrete cracks.Simultaneously decreasing strength. In addition, some cement at 35є with decomposed, with the strength of cement paste decreases.Therefore, when concreting in southern Russia at high ambient temperatures plus the normal hardening is necessary to maintain the required humidity and protect the concrete from the surrounding high temperature.

As long as the temperature does not exceed 20 - 25є C, concrete requires only moisture. Therefore, in the first two weeks after laying concrete watered and cover from wind or mat mat. If the sun was baking, the matting and mats to protect the concrete from excessive heat.

If the air temperature rises above 35є C, is urgently needed to protect the concrete from the sun's rays. Only in this way can provide normal conditions hardening button and obtain the specified strength!

Дата добавления: 2015-08-27