| you are: Structurally-mechanical properties of the cement test
According to P.A.Rebindera's constructed by a principle of intensity of energy of communication classification, all forms of communication of water in a cement stone can be divided into three groups.
The Chemical bond is the strongest. Chemically connected water leaves at prokalivanii, therefore it name still ' not evaporated ' water. Quantity of chemically connected water W usually express in% or shares from weight of cement. вагонка
Physical and chemical communication is characteristic for the adsorbtsionno-connected water which are in a time of cement gel; this communication is broken at drying. Обувной интернет магазин, сапоги.
Physicomechanical communication - in this case capillary pressure causes water deduction in a capillary time of a cement stone. The Adsorbtsionno-connected and capillary water deleted at drying, is called still ' as evaporated '. Quantity evaporated, i.e. The water not connected chemically define, applying as the drying agent ice at temperature-78В°S. Losses at prokalivanii the dried up test of a cement stone define chemically connected (not evaporated) water.
The Cement stone which is mineral glue, fastening filler grains, should possess sufficient own durability and adhesion, i.e. It is good to be linked to (grow together) to filler grains. These properties of a cement stone depend on quality and quantity of new growths, volume and character of a time.
Quality of new growths in a cement stone is defined by their structure and dispersion. Quantity of new growths in direct ratio degrees of hydration of cement and, reacted part of cement numerically equal to the relation with water to a cement lump. Hydration degree can be defined by a quantitative x-ray method or under the maintenance of the connected water w, not evaporated at drying.
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