The accelerating agent is a kind of admixture that makes cement concrete set and harden quickly. The early accelerator was powdery material, containing high Cl components that would cause the corrosion of steel bars in concrete. It has experienced the development from high alkali to low alkali and non-alkali, and from powder to liquid. The so-called accelerator alkalinity does not refer to the PH value of the accelerator, but refers to the content of alkali metal ions in the material, mainly K+ and Na+. Earlier...