Many additional ingredients can be added to a basic concrete mix in order to change the properties of the resulting concrete. The following list shows some common admixtures (additives) and additional ingredients and their basic purposes:
- Accelerators speed up the hydration, or hardening, of the wet concrete. Often used in colder temperatures so the concrete crew has less waiting time between placing and finishing the concrete.
- Retarders slow the hydration, or hardening, of the wet concrete. Often used in hotter temperatures so the concrete doesn’t set too quickly, allowing the concrete finishing crew proper time to finish their work.
- Air entraining agents add and help distribute tiny air bubbles throughout the concrete. These tiny air bubbles help the concrete resist the freeze-thaw cycles with much less cracking and damage.
- Plasticizers and Superplasticizers improve the workability of the concrete during the wet (or plastic) stage, allowing the concrete to flow more easily. They are particularly helpful when placing concrete around congested rebar arrangements. Alternatively, Plasticizers and Superplasticizers can be used to lower the water content in the concrete while keeping a decent level of workability.
- Increte – Integral Color changes the color of concrete for aesthetic reasons. It comes pre mixed in concrete upon delivery. With our state-of-the-art color machine, we can match hundreds of colors from various manufacturers.
- Mid-Range Water Reducers can affect up to 15% water reduction in a given mix while maintaining workability. These reducers enhance the mix by decreasing the water-cement ratio. This avoids the adverse effects of too much water, such as decreased strength, excessive air content, vulnerability in cold temperatures and all manner of surface defects – including shrinkage cracking.
- Damp Proofing Admix protects foundations against moisture in surrounding soils, but not against hydro-static pressure.
- Waterproofing Admix seals walls/foundations completely from water migration when used in correct dosage.
- Corrosion Inhibiting Admix prevents corrosion of steel reinforcement.
- Microfiber controls plastic shrinkage cracking in concrete caused when the surface shrinks when water evaporates from a top layer too highly concentrated with water and fines (sand and cement). Fibers serve to maintain proper distribution and spacing of aggregate particles and mortar.
- Macrofiber is synthetic fiber that serves as reinforcement when used in correct dosage and can replace rebar. Savings can be realized in the delivery, cutting, placing and tying of rebar. Space between joints can also be increased.