Latent hydraulic material

Latently hydraulic materials are also able to react hydraulically, but only in the... 

Latent hydraulic materials are also able to react hydrauhcally, but only in the presence of at least small amounts of a snitable activator. They are usually glassy or amorphous, and contain CaO, Si02, and AI2O3 as their main oxide constituents. Granulated blast furnace slag is the most widely used latent hydrauhc material. 

Activator—a substance that has to be added in small amounts to a latently hydraulic material to make it hydrate. 

Latently hydraulic material—material which—if ground to a powder—reacts in the presence of small amonnts of a suitable activator at ambient or moderately elevated temperatnres with water, to yield a hydrate (or hydrates) causing setting and hardening. 

Mineral additions may be broadly categorized as pozzolanic materials or latent hydraulic cements. Neither type reacts significantly with water at ordinary temperatures in the absence of other substances. Pozzolanic materials are high in Si02 and often also in AI2O3, and low in CaO they are sufficiently reactive that mixtures of them with water and CaO produce C-S-H at ordinary temperatures and thereby act as hydraulic cements. If they contain AI2O3, calcium aluminate or aluminate silicate hydrates are also formed. Because they are low in CaO, this component must be supplied in stoichiometric quantity. In a composite cement, it is provided by the Portland cement through decreased formation of CH and decreased Ca/Si... 

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