Concrete is a mixture of aggregates and binders that set when crystallization of the cement occurs as a result of hydration (combining with water). Typically, concrete utilizes a high percentage of water to allow even mixing and hydration of the binder. As the concrete sets, the water which evaporates leaves behind a void in the concrete.
These voids weaken the concrete and results in cracks and small holes in the surface when corrosives, water, and freezing water gets into these gaps, the material is eroded and the strength of the concrete is diminished. This progresses at a geometric rate and at some point the concrete becomes unstable.
Additionally, as cracks deepen, water penetrates to the supporting steel rebar. When rebar rusts, it expands and further destroys the concrete, causing significant weakness in such structures as parking, airport ramps, bridges, high-rise buildings and concrete balconies. There have been reports of balconies exploding off the sides of high-rise structures from this kind of failure.
GrailCoat DuraFlex is a concrete acrylic coating mix designed to solve the problem.
- The water required to adequately crystallize concrete is approximately 8%- the same as in the GrailCoat DuraFlex mixture- so no excess water is available to evaporate and cause gaps. The balance of the liquid consists of acrylic polymers, which create flexibility in the coating.
- The aggregate blend in the DuraFlex powder is designed for maximum density.
- The combination of low water and dense consistency creates a nearly impenetrable coating. The density does not allow the transmission of water molecules, but does allow the transmission of water vapor, allowing the eventual off-gassing of any trapped moisture.
- The flexibility created by the acrylic polymer base greatly reduces brittleness -and creates a tough surface that holds up in harsh environments and high traffic areas.
Uses of GrailCoat DuraFlex
- Parking Structures - DuraFlex applied as an intermediate coating for parking structures and structural elements of pre-cast concrete has proven to prevent water transmission to structural steel.
- High Traffic Surfaces - DuraFlex applied as a top coat with embedded aggregates (for traction) has proven to be a winner for parking structure surfaces and airport ramps subject to salt and other corrosives deposited by cars and trucks.
- Exterior Coating - DuraFlex used as an exterior coating, instead of stucco, has shown to be an excellent deterrent to salt air corrosion for beach-high rise structures.