Concrete fiber that keeps slabs from cracking
Fortress Concrete Fiber is a fibrillated polypropylene micro fiber for concrete. One pound per cubic yard, added straight to the mix, controls plastic shrinkage cracking and toughens the finished concrete. Certified to ASTM C1116 & ASTM C1579.
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Easy to use
Water-soluble bags go straight into the mix, by hand or machine, at any stage of mixing.
Three-dimensional crack control
Fibrillated fibers disperse through the whole batch to control plastic shrinkage cracking.
Tougher concrete
Increases performance against shattering and abrasion, reduces water permeability, and resists corrosion and chemicals.
No clogged guns or pumps
Fibrillated and cut for instant dispersion; reduces rebound and controls sagging on shotcrete.


Micro fiber, mixed in, working through the whole pour
Fortress Concrete Fiber is a fibrillated polypropylene micro fiber for concrete, cut short so it disperses instantly and reinforces the concrete in three dimensions. It is made for slab-on-grade, curbs, driveways, sidewalks, basement floors, garage floors, colored concrete, small precast products: anywhere the goal is to control plastic shrinkage cracking while improving basic durability.


One bag per yard. Drop it in the mix.
The standard dose is 1.0 lb per cubic yard (0.6 kg per cubic meter). Bags are water-soluble paper or plastic, so the whole bag goes into the mixer: a 1 lb bag for one cubic yard, a 5 lb bag for five.
Add the fiber at any stage of mixing, by hand or by machine, then mix at the time and speed the mixer manufacturer recommends, usually four to five minutes, so the fibers spread evenly through the batch.
Boxes hold either 40 one-pound bags or 8 five-pound bags, so a crew can dose to the batch size instead of guessing.
Dosage and packagingOrder Fortress Concrete Fiber from SOBX Chemicals
Single boxes ship from SOBX Chemicals in Graham, North Carolina. For pallet pricing and freight, call (336) 603-8029 or email [email protected].
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