Senior Petrographer, Wiss, Janney, Elstner Associates, Inc., Austin, Texas
(Received 3 December 2004; accepted 10 November 2005)
A linear regression equation is developed between the paste volumes via the point count method and total cementitious materials contents of 31 concrete samples with known mix proportions. The equation has a coefficient of determination (R2) of 0.96 and a standard deviation of 13.6 kg/m3. The equation can be used to calculate the total cementitious materials content based on the paste volume measured via point count and the water-to-cementitious-materials ratio estimated petrographically, and the result is more accurate than the traditional method currently used by many concrete petrographers. The equation is equally effective for portland cement concrete and concrete containing fly ash. In addition, the effect of fly ash, and the traditional method for estimating the cementitious materials content are further discussed.
Paper ID: JAI13057