Water reducing agent refers to an additive that can reduce the amount of water used for mixing under the condition that the consistency of the mortar is basically the same. Water-reducing agents are generally surfactants, and are divided into ordinary water-reducing agents, high-efficiency water-reducing agents, early strength water-reducing agents, retarding water-reducing agents, retarding high-efficiency water-reducing agents, and air-entraining water-reducing agents, ect.
Ordinary water reducer: additive that can reduce the amount of mixing under the condition that the consistency of the mortar is basically the same.
High-efficiency water reducer: additive that can greatly reduce the amount of water used under the condition that the consistency of the mortar is basically the same;
Early strength water reducer: additives with both early strength and water reducing functions. Some retarding water reducing agents are compounded by retarding agents and water reducing agents; Retarding high-efficiency water reducing agents: additives with both retarding and substantial water reducing functions. Combining retarder and super plasticizer;
Air-entraining water reducing agent: an additive that has both retarding and water-reducing functions；
Some air-entraining water reducing agent are compounded by air-entraining agents and high efficiency water reducing.
Development history of water reducing agents
- The development of water reducing agent originated in the 1930s. The first water reducing were used in concrete, and the water reducing agent used in dry mortar were all concrete water reducing agent. Since the 1930s, the United States, British, Japan and other countries have started to use water reducing agents in highways, tunnels, and underground projects. The water reducing agent used at this stage mainly includes organic substances such as sodium rosin, Sodium lignosulfonate and stearate soap. With the rapid development of the construction industry during this period, ordinary water reducing agents have been widely used and developed rapidly. From the 1960s to the 1980s, it was the synthesis and application stage of water reducing agent, namely naphthalene-based and melamine-based water reducing agent.
- Japan is one the most successful countries in the development and application of water reducing agent.