It sounds like interesting stuff, and Nycon is a fine company ... I
bought 40 lbs of their nylon fibers and had the stucco subcontractor add
it to the scratch coat (first coat) when they coated my house since
nylon holds its strength in high alkalai environments (like cement)
better than standard glass fibers do. Nycon also makes steel fibers, and
I think carbon threads. The PVA material is apparently a new product for
them since I last dealt with them.
If the prices shown at the link below are any indication, though, I
doubt you're going to want to use PVA fibers at 44 lbs per cubic yard to
replace normal rebar. You're talking about a cost adder around $275 per
yard (!) if I did the math right.
Aside from that, though, the following two quotes from the web page you
referenced lead me to suspect that rigid structures like tower
foundations may not be the intended application for this material. The
suggested applications list situations where flexing is desirable,
although I have to admit that a cast block of aluminum would probably
still make an excellent tower base ;)
"This new class of materials produces a mortar that behaves like
aluminum in flexural and tensile deformation."
"In tensile or flexural deformation, the material more closely resembles
the ductility of aluminum."
You would probably also have a building code approval issue if you tried
to rely on fibers only. In general, fibers are considered by the
concrete industry to be only secondary reinforcement for the purpose of
reducing cracks. Even the spec sheet on the nylon fibers I bought had a
disclaimer for that, and steel rod reinforcement is generally required
for structural applications. PVA fibers in the specified dosage might be
equal or greater in strength (although apparently not in rigidity), but
I'll bet it will take some time for the codes and inspectors to catch up.
Rudy Bakalov wrote:
> The specs for KURALON™ RECS15 state: "The optimum fiber dosage of PVA-ECC at
> up to 44 lbs per cubic yard offers the possibility of reduced-steel and even
> steel-free reinforcement."
> Has anyone considered or even tried replacing rebar with PVA fibers?
> Rudy N2WQ
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