| you are: Porosity of a cement stone
In practice apply basically concrete mixes with VTS=0,4-0,8 which give in to consolidation by vibrating, therefore porosity of a cement stone in real concrete makes 30-50%, and its durability will be 20-100 MPa. школа танго москва
Speed of interaction klinkernyh minerals with water can be characterised increase in degree of their hydration in time.
Most quickly gidratirujushchimisja minerals cement klinkera are trehkaltsievyj aluminate and trehkaltsievyj silicate; the slowest hydration occurs at dvuhkaltsievogo silicate.
Trehkaltsievyj silicate quickly hardens and gets high durability. Trehkaltsievyj aluminate differs very fast increase of durability, but further it does not change almost.
Thus, the increase in the total maintenance trehkaltsievogo silicate and trehkaltsievogo aluminate in cement klinkere is necessary for reception bystrotverdejushchih portlandtsementov.
The Increase in a specific surface and durability of cement in initial terms tverdenija (to 3 sut) speaks maintenance increase in cement of particles in the size less than 5 microns. Just in small fraction of cement less firm minerals - alit (C3S) and РЎ3Рђ, quickly reacting with water accumulate. Full hydration of fine grains of these minerals occurs already during the first 3 sut after zatvorenija cement water and gives a corresponding prize in initial durability.
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