Concrete admixtures are divided into four categories based on their main functions:
2.1 Additives for improving the rheological properties of concrete mixtures. Including various water reducing agents, air entraining agents, and pumping agents.
2.2 Admixtures for adjusting the setting time and hardening performance of concrete. Including retarders, early strength agents, and rapid setting agents.
2.3 Additives for improving the durability of concrete. Including air entraining agents, waterproofing agents, and rust inhibitors.
2.4 Additives for improving other properties of concrete. Including aerators, expansion agents, colorants, antifreeze agents, waterproofing agents, and pumping agents, etc