Concrete additives are abbreviated as admixtures, which are substances used to improve the performance of concrete.
According to the main functions, it is divided into four categories:
(1) Additives to improve concrete mixing and workability, including various water reducing agents, air-entraining agents and pumping agents, etc.;
(2) Additives for adjusting the setting time and hardening performance of concrete, including retarders, early strength agents and accelerators, etc.;
(3) Additives to improve the durability of concrete, including air-entraining agents, waterproofing agents and rust inhibitors, etc.;
(4) Additives to improve other properties of concrete, including air-entraining agents, expansion agents, antifreeze agents, coloring agents, waterproofing agents and pumping agents.
Water reducing agent
Superplasticizer:
Under the condition that the concrete slump is basically the same, the admixture that can greatly reduce the mixing water consumption;
Slow-setting and water-reducing agent: an admixture with both retarding and water-reducing functions;
Early strength water reducing agent: an admixture with both early strength and water reducing functions;
Air-entraining agent: an admixture that can introduce a large number of uniformly distributed, stable and closed tiny bubbles during the mixing of concrete;
Waterproofing agent: an admixture that can reduce the water permeability of concrete under hydrostatic pressure;
Rust inhibitor: an additive that can inhibit or reduce the corrosion of steel bars or other embedded metals in concrete.
Air-entraining agent: It is an admixture that forms a large number of pores in the concrete due to a chemical reaction during the preparation of the concrete and gas is released.
Expansion agent: an admixture that can produce a certain volume expansion of concrete.
Antifreeze: an admixture that can harden concrete at negative temperature and achieve sufficient antifreeze and strength within a specified time.
Coloring agent: It can prepare admixture for concrete with stable color.
Accelerating agent: an admixture that can quickly set and harden concrete.
Pumping agent: an admixture that can improve the pumping performance of concrete mixtures.
The materials used to make pumping agents include superplasticizers, retarders, air-entraining agents and thickeners