Calcium Nitrite Effect On Setting Of Cement At Various Temperatures

Abstract

Calcium Nitrite, which is used as corrosion inhibitor, accelerates stiffening rates of cement. This paper deals with the effect of calcium nitrate on setting times of cement pastes at various curing temperatures. Four pastes were used to study the effect of two dosages of calcium nitrate as well as the effect of an additional set-retarding superplasticiser on rates of hardening at 25, 35 and 50°C. The results indicated significant acceleration in setting as a result of either calcium nitrite addition or higher curing temperatures. The combined effect of calcium nitrite and high curing temperatures was very significant. Setting times were reduced by over 80% when comparing paste containing calcium nitrite at 50°C to plain cement paste at 25°C.