Concrete is a composite compound made by mixing cement, sand, water, and several aggregates, while admixture are materials that are added to concrete, cement, and mortar to enhance their properties.
There are different types of concrete admixtures available on the market which help to improve the building materials’ strength, durability, workability, and aesthetics. These are categorized into different types according to their physical and chemical properties.
Some of the most common types of construction admixtures include fiber admixtures, mineral admixtures, and chemical admixtures.
In this blog, we will discuss the different types of admixtures used in the construction industry today, including their uses and advantages.
Types of Concrete Admixtures
First, let’s look at some of the most popular types of admixtures used in construction –
Chemical Admixtures
Chemical admixtures are the most popular types of admixtures used in construction. They are used with cement, concrete, shotcrete, and mortar to enhance the construction materials’ properties.
Chemical construction compounds are further classified into different types depending on their functions and chemical composition. The most common types of chemical admixtures are air-entraining agents, superplasticizers, accelerators, retarders, and water reducing agents.
Let’s learn about the types of chemical admixtures in more detail:
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Water Reducing Agents
Water reducing agents, or water reducers, are chemical admixtures that are used with mortar, concrete, and shotcrete to lower the amount of water required to attain the desired workability. These admixtures reduce the water content to enhance the concrete’s durability and strength without the risk of cracking.
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Accelerators
Accelerators are chemical admixtures that are added to mortar, shotcrete, and concrete to shorten the hardening time. These admixtures are extremely useful to let concrete and mortar harden faster in cold climates and weather, where concrete usually takes longer to set. Apart from this, accelerators are also used to make emergency repairs where concrete needs to harden quicker.
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Retarders
Retarders are the opposite of accelerators. Retarder chemical admixtures are used with concrete, mortar, and shotcrete to prolong the hardening time. Retarder admixtures are mostly used in hot weather conditions and climate, where concrete tends to set too quickly. These chemical admixtures are useful when you need sufficient time to finish the concrete surface.
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Air-Entraining Agents
Air-entraining agents are chemical admixtures used with concrete, mortar, and shotcrete. These are designed to produce tiny air bubbles into the cement mix.
These air bubbles tend to lower the mass of the structure while increasing its workability, which also prevents cracking on the surface. Air-entraining agents are especially helpful to enhance the workability of concrete when the concreted surface is frequently exposed to freezing and thawing cycles.
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Superplasticizers
Superplasticizers are chemical admixtures that are added to mortar, concrete, etc. to enhance overall workability. These admixtures improve the fluidity of the cement mix without the need to add excess water. This is very helpful when the concrete needs to be placed or pumped in hard-to-reach areas.
Mineral Admixtures
Mineral admixtures are construction compounds added to mortar, cement, and concrete to boost their properties. Mineral admixtures are classified into different types according to their functions and chemical composition. Most used mineral admixtures include slag cement, silica fume, and fly ash.
Let’s find out more about the different types of mineral admixtures you can buy from leading manufacturers, Sakshi Chem Sciences Pvt Ltd in 2024 –
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Silica Fume
‘Silica Fume’ is formed during the ferrosilicon and silicon production process. It is added to concrete to increase durability, improve strength, and reduce permeability. It is also useful for lowering the amount of cement required, which further helps by reducing the pollution caused by the construction project.
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Fly Ash
Fly ash is formed from coal combustion in thermal power plants. It is used with concrete to lower permeability, improve strength, and increase workability. Fly ash also helps to lessen the volume of cement required in making concrete, which further reduces the pollution caused by the construction project.
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Slag Cement
Slag cement is produced during the steel-manufacturing process. This type of cement is used with concrete to enhance its durability, improve its strength, and ensure optimal sulphate resistance. It is also useful to lower the volume of cement required in making concrete and lower the overall carbon footprint of the construction project.
Fiber Admixtures
Fiber admixtures are construction compounds that are used with mortar, concrete, etc. to enhance their properties. These admixtures are further categorized into different types, according to their functions and chemical compositions.
Below are the common types of fiber admixtures used in the construction industry –
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Natural Fibers
Natural fibers are made from sisal, coconut husks, and wood. These fibers are added to cement, shotcrete, and mortar to improve crack resistance, durability, and impact resistance.
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Synthetic Fibers
Synthetic fibers in construction are admixtures that are made from nylon, polyester, and polypropylene. These admixtures are added to shotcrete, mortar, and concrete to enhance durability and ensure maximum crack and impact resistance of the concrete structure.
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Steel Fibers
Steel fibers are made from carbon steel and stainless steel. These admixtures are added to concrete to improve its impact resistance and increase its strength and durability. Steel fibers also help in reducing the risk of cracking and shrinkage during the hardening process of concrete.
Benefits of Concrete Admixtures
On the recent study on concrete admixtures show that the different types of concrete admixtures, let’s learn some of the major benefits of using construction admixtures in building projects –
Enhanced workability
Concrete admixtures enhance the workability of building materials, which makes it easier to place and get the desired finish. It also enhances the appearance and overall quality of the finish surface.
Lowered permeability
Admixtures also reduce the permeability of construction materials and make them more resistant to chemicals and water. This lowers the risk of damage from chemical attack and water seepage.
Improved strength
Concrete admixtures also enhance the durability of buildings by increasing their strength, which makes structures stronger and more resistant to regular wear-and-tear. Admixtures also enhance the overall lifespan of buildings and lower the maintenance costs too.
Conclusion
There are different types of concrete admixtures offered by leading manufacturers and suppliers Sakshi Chem Sciences in the market today. Construction experts recommend using admixtures according to your specific needs.
For instance, you will need to use a specific admixture to enhance the workability of concrete while a different admixture is used to improve the durability and strength of concrete structures.