We are all familiar with the typical rebar used in concrete reinforcement applications, but many have
never heard of Helix steel, or twisted steel micro rebar (TSMR). Micro rebar is roughly 1” long by .02in in diameter.
Due to its patented twisted geometry, Helix greatly increases concrete bond strength with the
concrete mix. Helix provides a torsional resistance rather than a pull-out resistance. This is similar to
trying to pull out a screw from a piece of wood vs. a nail. Some other design benefits are:
Improved concrete ductility
Greatly improved strength over concrete reinforced with rebar
Shear Strength=250% increase
Modulus of rupture=10% increase
Durability (concretes ability to resist repeated beating) =50% increase
Provides LEED credits
Installation ease is also greatly improved due to the reinforcement already being mixed in with
the concrete. An average of 1 day of labor is saved for every 10,000 sqft of construction. Although the
cost of helix is roughly equal to rebar; there is a 20% direct cost savings due to the reduction of labor.
Similar to rebar, Helix can be used for slab on grade, slab on metal deck, above and below grade
walls, and footings. Because Helix settles into the concrete paste, it is not visible on the exterior.
For typical below grade walls, all standard rebar can be eliminated except around openings, in which (1)
#4 is required. The amount of Helix required in the concrete mix for an 8’ wall is 9-12lbs/yd3 depending
on the soil pressure and the height of unbalanced backfill.
Since 2007, Helix has been used in over 8,000 residential homes for poured walls and slabs.
Helix steel is the only discontinuous concrete reinforcement product in the world with an ISO certified
design manual that can be followed to design vertical applications.