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UltraFiber 500 FAQ


UltraFiber 500 Pellets
Does UltraFiber500 reduce cracking?
UltraFiber 500 reduces plastic shrinkage cracking. Over time, these plastic shrinkage cracks can grow into more significant cracks. Penetration by salts, harmful chemicals, and moisture through these plastic shrinkage cracks poses a significant threat to the structural integrity of concrete. Addressing plastic shrinkage cracking reduces the future potential for cracking.

What is plastic shrinkage cracking and how is it reduced by UltraFiber 500
Plastic shrinkage cracking occurs as concrete cures and loses moisture. The more rapid this moisture loss, the more severe the shrinkage cracking. A variety of environmental issues can make this worse. There are two ways UltraFiber 500 helps reduce cracking. Like other microfibers, UltraFiber 500 keeps concrete from “pulling apart” during plastic shrinkage. However, unlike other fibers, UltraFiber 500 absorbs moisture, storing it in the concrete and improving cement hydration. This increases strength and reduces micro-crack development.

Does UltraFiber 500 affect finishing?
UltraFiber 500 does not adversely affect concrete finishing. Unlike other microfibers, UltraFiber does not clump, ball, fuzz, or build up on tools. It is effectively invisible in concrete and yields an aesthetically unaffected finish. Most importantly, UltraFiber 500 does not change how the concrete is finished or placed. Finishers would never know they were using fiber.

Does UltraFiber 500 affect hydration?
UltraFiber 500 is hydrophilic. This means, unlike synthetic fibers, UltraFiber 500 absorbs moisture. This moisture is then reabsorbed by the concrete as it cures. This leads to improved curing, better strength, and more resilient concrete.

Is UltraFiber 500 compatible with colored concrete?
UltraFiber 500 is the best fiber for colored concrete. Because they are so small, each individual fiber in UltraFiber 500 is virtually invisible in concrete compared to larger synthetic fibers. UltraFiber 500 is the only microfiber that absorbs integral color and stains, which means it won’t be visible.

How long does UltraFiber 500 last in concrete?
UltraFiber 500 is specially treated to be alkali resistant and meets industry standards for durability. In testing, UltraFiber 500 has shown it can withstand alkali conditions greater than what is found in concrete. You can count on UltraFiber 500 to last in concrete and provide exceptional crack reduction.

Does UltraFiber 500 improve Freeze/Thaw Durability?
UltraFiber 500 improves freeze/thaw durability by as much as 50% versus plain concrete. Using UltraFiber 500 in concrete reduces shrinkage cracking and internal microcracking. UltraFiber 500 increases the strength of concrete and makes it less susceptible to the stresses of the freeze/thaw cycle.

How does UltraFiber 500 get added to concrete?
Adding UltraFiber 500 is easy. To manually dose UltraFiber 500, add the convenient 1 pound or 1.5 pound (gram weighted bags available) water-soluble bags to the truck, then urn the mixer on high speed for at least 100 revolutions. The UltraFiber 500 Automated Dispenser makes this easier by integrating into existing batch plant and control software. In most traditional mixes, the large aggregate breaks up the fiber and evenly disperses it after only a few minutes. Please refer to the full mixing guide on