Additives are materials that are used to modify the properties of concrete. Admixtures, in addition to cement, water and aggregate, are added to concrete immediately before or during the mixing process. Additives can be used to reduce construction costs and ensure some required characteristics of fresh concrete.
The importance of using concrete additives
Apart from cement, aggregates (sand) or water, any other material added to concrete is known as admixture. Although these materials may not be needed, sometimes in special conditions, concrete additives play the role of an auxiliary force.
By having engineering science and paying attention to the ingredients of concrete and checking the type of aggregates and the ratio of water to cement, it is possible to provide things like the efficiency and resistance of concrete in natural conditions. If it is not possible or there are special conditions, such as frost, high air temperature, increased wear or long-term exposure to degreasing salts or other chemicals, additives are added to concrete.
The benefits of concrete additives
The benefits of using concrete additives include:
- Articles of the Execution of the amount of Niaz Ra Mahsh Mihads and Bett Betr Ra, an economic eyesight coupled with the disbursement of Mikknand. Ra Afzaish Maydada. May Dahdad and the Righteousness of the problem of kicking the heat of the arsenal of Batn, the victory of the Maymand. Mikknand.
The main types of concrete additives
Concrete
Concrete foaming additives are used to trap microscopic air bubbles in concrete. These materials improve the durability of concrete, increasing its resistance to damage caused by freezing cycles. Foaming agents provide better performance when working with concrete and improve resistance to water penetration.
It also requires less water per cubic yard than concrete that does not contain encapsulating materials, thus improving the water-cement ratio. Materials used in foaming additives include polyethylene oxide polymers, some fats and oils, sulfonated compounds and detergents.
Water -reducing materials
Water-reducing additives reduce the amount of water needed to produce concrete with a specific consistency. It is also possible to improve the slump of concrete without the need for additional water, thus lowering the water-cement ratio.
By reducing the water-cement ratio, water-reducing additives can increase the strength of concrete and at the same time maintain the required performance. Lignin sulfonic acids and metal salts are usually used as water reducing additives.
Lubricant additive
Superplasticizers are organic compounds that turn concrete into a more fluid mixture. They work by coating the cement particles and causing them to separate from the clumps that usually result from mixing cement and water.
Lubricating additives give each cement particle a negative charge, which makes them repel each other and have a more accurate distribution. They are used either to facilitate the placement of concrete or to reduce the amount of water in the concrete mixture to increase its strength.
Accelerator additive
Accelerating additives increase the setting speed of concrete. In addition, they accelerate the development of concrete strength. By using type 3 Portland cement and accelerating additives, the strength development of concrete can be improved.
By curing concrete at higher temperatures or reducing the ratio of water and cement, concrete setting can be accelerated. Accelerators are usually used in cold weather to obtain the initial strength of concrete to compensate for possible frost damage.
Delayed additives
Set retarding additives are basically the opposite of accelerators. They increase the time needed to process concrete; In other words, they reduce the time of cement paste. Retarding additives are usually used in hot weather.
By using retarding materials, less water can be used to process concrete. With the presence of retarding additives, it is possible to obtain the appropriate water-cement ratio and increase the final strength.
Other concrete additives include the following:
- Khakester Bady
- Silica vapor
- Sirbarah Pland Bland
- Poosolan
- Bazdarindhi Khord It is attributed to it.
