"Setting Accelerator Calcium Nitrate Fundamentals, Performance and Applications"

Abstract

The effectivenss of calcium nitrate (CN) as a setting accelerator for cement is dependent on the cement type. The reason for this is explained by the mechanisms for set acceleration, and parameters for predicting the set accelerating efficiency of CN from cement characteristics is pointed out. Performance characteristics such as temperature evolution profile in insulated concrete (i.e., semi-adiabatic) and early compressive strengths (from 8 h) of concretes cured at 20 degrees C for different additions of different soluble calcium salts are demonstrated. The accelerating effect of CN was compared to additions of both calcium acetate and formate on equimolar concentrations of Ca(2+). Calcium acetate and formate gave about the same accelerating effect, while CN showed greater acceleration. Examples are given for field use and potential applications of CN in concrete.