ASTM C1738/C1738M-19 PDF Download

The ASTM C1738/C1738M-19 standard provides guidelines for conducting high-shear mixing of hydraulic cement pastes in laboratory research on rheology of cement systems. The purpose of this practice is to obtain a cement paste with rheological properties similar to those obtained in concrete, even when the aggregate is absent, by applying significantly higher levels of shear compared to other mixing methods like C305.

The standard emphasizes that the high-shear mixing technique described in this practice is more effective in thoroughly mixing the paste compared to other methods. The high-shear mixing imparts sufficient energy to the cement paste to achieve homogeneity and consistent rheological properties.

The standard also provides information on unit conversions, stating that both SI units and inch-pound units are acceptable. However, it stresses that the values in the two systems are not exact equivalents and should be used independently, as combining values from both systems may lead to nonconformance with the standard.