fiber reinforced concrete

huangyhg

fiber reinforced concrete
what are the primary uses for fiber reinforced concrete?
does anyone have any good experience with frc?
any good references would be greatly appreciated.
small crack control, and to create fuzzy, hairy concrete. (smile)
mike mccann
mmc engineering
abusementpark....fiber is good to enhance the properties of concrete, but not to replace rebar.  steel fiber does a good job of increasing the modulus of rupture for flexural strength.  it also increases the compressive strength, but not in the same proportion.
polypropylene fibers, in my opinion, are oversold.  they do not do as much for the concrete as the manufacturers would have you believe.  yes, they will decrease the early crack potential.  this means that the space between cracks will increase, but also the width of cracks will increase.  they do not stop cracking altogether.
i have had good experience with steel fibers in concrete, not so good with polypropylene.  i know of one pavement section used as a loading dock and dumpster pad that i designed over 20 years ago and it is still performing quite well, with no cracks other than at control joints.  we added steel fiber to the asphalt on the same project.  the asphalt has performed amazingly well for over twenty years.
see
ron, what specific problems have you had with polypropylene fibers?
abp...just that many ready mix producers will use poly fibers to cure their mix deficiencies (high water-cement ratio particularly).  shrinkage of the mixes has been high, resulting in wide, but longer spaced shrinkage cracks.
workability is often an issue with any fiber.