FIBER OR WIRE 1

[37ed]

I have a contracter that wants to add his own fiber to concrete mixers on site.This will save him money.I don't have a problem with him saveing some money.

He called me and ask if I would mind.He has indicated that he is going to use the same 1 lb bags as are used at the concrete plant,dump in ten per truck,and spin for 5 min.

Well the plant does it the same way,but I am feeling concerned about him doing it right.This is a sub for wire in the slab and will save him more money.

How do we feel about fiber over wire,and letting him mix the fiber on site?

I am looking for comments
Thank

 

[SlideRuleEra]

I started specifying polypropylene fibers on "low priority" industrial slabs on grade in 1985 to see how it would work. At that time it was standard practice to add the fibers to the concrete mix on the job site, more or less as you described. (Concrete batch plants in our area did not offer fiber reinforcement then.)

If the slab was designed to use WWF properly, fiber substitution worked well each time (you did get "hairy concrete" then, but it is my understanding this has been corrected) - by 1990, we discontinued WWF for slabs on grade (used fiber instead).

Keep in mind that the fibers are not considered reinforcement by ACI 318.

Two more comments:
1. Follow the fiber manufacturer's current instructions, not the contractor's recommendations.
2. Since it does reduce costs, perhaps the client deserves a share of the savings.

http://www.SlideRuleEra.net

 

[boo1]

With the labor of double handling the mix, I suspect he will not save money over the fiber being added at the batch plant.