Post Date:9,Feb,2026

Incompatibility between admixtures and cement is a frequent occurrence, especially when using pumped water-reducing agents. Determining the primary cause requires testing and analysis; achieving compatibility necessitates experimentation.

The first step should ideally begin with testing the pH value of the cement to be used, i.e., its alkalinity. This can be done with pH test paper, but a pH meter or pH pen is preferable.

The second step is investigation. The first part of this investigation is obtaining clinker analysis results for this type of cement whenever possible. Cement plants perform rapid fluorescence analysis of clinker every shift, providing a monthly average. While this data isn’t typically included on the cement certificate, it’s not confidential information. Obtaining clinker analysis results from any recent day is also acceptable.

The third step is to determine the saturation dosage of the high-efficiency water-reducing agent used in this type of cement. If two or more high-efficiency water-reducing agents are mixed, the saturation dosage point should be determined through a cement paste test based on the total amount mixed. The closer the dosage of the high-efficiency water-reducing agent is to the saturation dosage of the cement, the better the compatibility will be. However, the saturation point of early-strength cement is generally high, requiring traditional high-efficiency water-reducing agents to exceed 1% or 0.8% (calculated based on solid weight). For pumping agents, which typically have a dosage of no more than 2.5%, achieving the saturation point is unrealistic; even approaching it is impossible. The main approach is to rely on the compounding of different high-efficiency water-reducing agents and their combination with various retarders to achieve the desired adaptability.

The fourth step involves trial mixing of composite admixtures and using neat cement paste tests to identify suitable setting regulators and appropriate dosages. The results of the second step should be considered to select the most effective setting regulator.