Self consolidating masonry grout

05 Jul

The chemical process for hydraulic cement found by ancient Romans used volcanic ash (pozzolana) with added lime (calcium oxide).The word "cement" can be traced back to the Roman term opus caementicium, used to describe masonry resembling modern concrete that was made from crushed rock with burnt lime as binder.The volcanic ash and pulverized brick supplements that were added to the burnt lime, to obtain a hydraulic binder, were later referred to as cementum, cimentum, cäment, and cement.Cement is used with fine aggregate to produce mortar for masonry, or with sand and gravel aggregates to produce concrete.Cements used in construction are usually inorganic, often lime or calcium silicate based, and can be characterized as being either hydraulic or non-hydraulic, depending upon the ability of the cement to set in the presence of water (see hydraulic and non-hydraulic lime plaster).

Hydraulic cements (such as Portland cement) are made of a mixture of silicates and oxides, the four main components being: The silicates are responsible for the mechanical properties of the cement, the tricalcium aluminate and the brownmillerite are essential to allow the formation of the liquid phase during the kiln sintering (firing).The chemistry of the above listed reactions is not completely clear and is still the object of research.Perhaps the earliest known occurrence of cement is from twelve million years ago.