C-S-H gel

During the course of reaction of C₃S and C₂S with water, calcium silicate hydrate abbreviated C-S-G and calcium hydroxide, Ca(OH)2 are formed.C-S-H are very important products. It is the essence that determines the good properties of concrete. It makes up 50-60% of the volume of solids in a completely hydrated cement paste.

FORMED & ROLE OF C-S-H GEL

During the course of reaction of C₃S and C₂S with water, calcium silicate hydrate abbreviated C-S-G and calcium hydroxide, Ca(OH)2 are formed.

This is the main reaction product and is the main source of concrete strength. It is often abbreviated, using cement chemists notation, to C-S-H, the dashes indicating that no strict ratio of SiO2 and CaO IS INFERRED. The Si/Cs ratio is somewhat variable but typically approximately 0.45-0.50 in hydrated Portland cement but up to perhaps about 0.6 if slag or fly ash or micro silica is present, depending on the proportions.