Basic selection rules for concrete admixtures

The types of concrete admixtures should be selected according to project planning and construction requirements, and determined through experiments and technical and economic comparisons. The specific selection requirements are as follows:

1. It is prohibited to use additives that are harmful to the human body and pollute the environment.

2. The cement used in concrete mixed with admixtures should be Portland cement, ordinary Portland cement, slag Portland cement, pozzolanic Portland cement, fly ash Portland cement and For composite Portland cement, the adaptability of the admixture and cement should be checked and used only if it meets the requirements.

3. The materials used in concrete with admixtures, such as cement, sand, stone, admixtures and admixtures, should comply with the relevant national regulations. When trial mixing concrete mixed with admixtures, the raw materials used in the project should be selected. The inspection items should be determined according to the planning and construction requirements. The inspection conditions should be the same as the construction conditions. When the raw materials used in the project or the performance requirements of the concrete change, the trial should be carried out again. With experiments.

4. When using different types of admixtures in combination, attention should be paid to their compatibility and impact on concrete properties. Tests should be conducted before use and the requirements can be met before use.

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