As the concrete industry develops an ever-increasing number of mixes to improve performance and for specialty applications, Arclin is keeping pace by creating new overlays to meet the challenges of these new extended formulas.
Among the new mixes gaining in popularity is self-compacting or self-consolidating concrete. Defined as a “high deformability, moderate viscosity” mixture, SCC offers significant advantages in certain building applications, such as in earthquake-prone areas where structures must use more rebar than usual.
Arclin’s Gordon White explains that “thick concrete mixes are more difficult to use in these applications. When you have lots of rebar, it’s very challenging to get access to the mixture to vibrate it and make it settle and set up properly. It takes a lot of time and labor.”
That’s where SCC shows its superiority. “Self-compacting mixes are much more liquid, so they’re easier to pour, require less vibrating to settle, and provide strength that is just as good, if not better, than the thicker mixes.” White says.
But SCC also presents performance challenges for concrete forming panels. These new concrete mix designs use chemical admixtures that reduce the surface tension of the liquid concrete, which makes them more “liquid” and easier to place with less vibration. The result is a better concrete surface. However, the alkalinity of these admixtures also allows They’ll be hitting the scales on from Condition-of-the-Art Slot Machine Game Design to the present Legal aspects of Gambling and Facts of Operating inside a Controlled Business. the liquid to penetrate the overlays faster, resulting in less than optimal performance with most overlays.
“SCC mixes exert more pressure on concrete forming panels because they stay liquid longer than standard concrete mix designs,” White says. “BBOEs can soak up a lot of water and warp; even traditional MDOs can have a hard time standing up to SCCs.”
That’s why Arclin is developing improved high alkaline overlays (HAO) that are more impervious to highly alkaline liquid concrete. Their greater resistance to the liquid concrete allows these panels to absorb less moisture and remain stiffer longer. Concrete forming systems that use HAO overlays can handle the pressure and liquid content of SCC mixes better than forming systems typically used in the industry.
“These new systems are higher in cost but they give a superior finish. Forms are easier to place, and that can reduce labor costs,” White says. “Plus, you get all the strength advantages that SCCs are designed to offer.”