Concrete identifiers are used by concrete plants to increase the amount of aggregate added to the mix as it is formed at a concrete plant. A concrete densifier is also a liquid additive added to the concrete mixture before it is poured. The purpose of using a densifier is to improve the quality of concrete by increasing its compressive strength, decreasing its elasticity, and increasing its ability to bear expansion and contraction.
There are two types of concrete densifiers on the market. One is an epoxy resin which is mixed with water before the concrete is poured. Another is a thermosetting resin which must be mixed with a carrier compound, then poured into the concrete. Both concrete densifiers serve the same purpose; they increase the compressive strength of concrete, thus decreasing its elasticity. This allows the concrete to be poured quickly and more thoroughly, while also allowing concrete manufacturers to produce more concrete products. However, there are some important differences between the two types of concrete densifiers.
Epoxy resin types of concrete densifiers include cement-based aggregates, such as sand or gravel, and fine aggregate, such as shale. These aggregates are combined with water and squeezed or sprayed to form the desired texture and mixture. Epoxy resin types of concrete densifiers are used primarily for exterior applications because they can be coloured, thereby changing the concrete’s colour to blend seamlessly with the surrounding soil or landscaping. Because these types of concrete identifiers cannot be used in interior applications, they must be colour coated before use. This process makes certain that the concrete has a smooth, uniform surface. Most epoxy resin types of concrete densifiers are also fine-tipped so that they will not settle or bulge while the concrete is being mixed.
Fine Aggregate Concrete Densifiers
Fine aggregate concrete densifiers include polystyrene and polyurethane powders. Unlike polystyrene and polyurethane, these materials are insoluble in water, thus making them resistant to water, grease, oil and other contaminants that can stain concrete surfaces. Besides, fine aggregates have larger surface areas, which enables them to cover a larger area of a concrete floor and achieve greater compressive strength. However, this means that these types of concrete densifiers require more frequent application than other types of identifiers.
Sand and Grit Concrete Densifiers
Sand and grit concrete densifiers consist of finely ground sand and/or silica particles. These materials are mixed with oil and water, which in turn creates a chemical reaction that causes the bonding of the aggregate to the water. The concrete floors created through this type of chemical reaction have excellent compressive strength and excellent resistance to staining and damage.
Aggregates and aggregate mix provide a back-fill capability for concrete floors. Backfill concrete densifiers allow concrete surfaces to be filled when hardening and compacting is required without the use of additional filling agents. Backfill concrete densifiers are most commonly used when concrete surfaces have been formed through the use of a concrete pressing machine. This type of concrete densities produces concrete that is dense enough to resist staining but also thick enough to hold the weight of the concrete mix. This results in concrete surfaces that are stronger, durable, and have excellent compressive strength.
When concrete densifiers are blended with an acid, they create a substance called Lime X. This mixture is highly soluble in water and reacts with the latex to form a thick paste that forms a protective layer on concrete surfaces. Lime X is an inexpensive identifier that can be combined with a variety of other ingredients to form a wide range of textures and designs. This is one of the many types of lime deposits that are used for backfill. Unfortunately, lime X is also extremely toxic to humans and must be avoided whenever possible.
Other types of concrete densifiers include silicon carbide, which hardens by forming a solid structure of silicon nitrate on the surface of the concrete. Silicon nitride is extremely dense, as well as very smooth, and can be used to avoid contact with moisture on the surface of the concrete before pouring the material into the mix. This makes it ideal for backfilling jobs. Silicon carbide is also suitable for use in mixing concrete without the use of lime to achieve the same effects.