Effects of slag on cement hydration by electrical resistivity characterization

Abstract

Abstract Non-contact resistivity measurement was used to characterize the early hydration characteristics of cement paste with different contents of slag, combined with other traditional methods such as hydration heat, compressive strength. The results show that the maximum compressive strength of sample P0.4SL20 was 34.4 MPa and 45.2 MPa at 3 d and 7 d, respectively. The addition of slag could reduce the hydration heat of slurry, which makes the second hydration exothermic peak shift to the left. The characteristic points on electrical resistivity differential curve with different slag contents had good correspondence with the corresponding characteristic points on hydration heat release curve of samples with different slag contents. A good linear relationship between electrical resistivity and compressive strength was shown as f c(3d) = 5.23992P(3d)-12.31066. The electrical resistivity method can be used to characterize the influence of slag on the hydration process of cement paste and predict its compressive strength.