1. Clotting time. High-efficiency water reducing agents generally have no retarding effect and may even promote the hydration and hardening of cement. Retarded high-efficiency water-reducing admixture is a compound of high-efficiency water-reducing agent and retardant. Under normal circumstances, commercial concrete mixing stations add a certain amount of retarder to the water reducing agent in order to delay cement hydration and reduce slump loss.
2. Air content. The currently commonly used polycarboxylate water-reducing agents have a certain air content, and the air content of concrete should not be too high, otherwise the strength of the concrete will be greatly reduced.
3. Water retention. High-efficiency water-reducing admixtures do not contribute much to reducing bleeding in concrete, and may even increase bleeding. Concrete bleeding increases when the dosage is excessive.
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