Concrete admixtures are divided into four categories according to their main functions:
1. Admixtures that improve the rheological properties of concrete mixtures. Including water reducing agent, air entraining agent and pumping agent, etc.
2. Admixtures that adjust the setting time and hardening properties of concrete. Including retarder, early strength agent and quick-setting agent.
3. Admixtures that improve the durability of concrete. Including air-entraining agents, waterproofing agents and rust inhibitors.
4. Admixtures that improve other properties of concrete. Including air-entraining agents, expansion agents, antifreeze agents, colorants, waterproofing agents, pumping agents, etc.
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