Cement or concrete

[Trainer]

Going to pour a slab for a garage. I have heard about the cememt/concrete with fiberglass in it. Was told by some that I would not need rebar, only the fiberglass/cement mix. Someone please give me some feedback on the use of the fiberglass/cement mix.

Will I need rebar and wire in the slab?

 

[Tig]

The last time I poured cement the guy driving the truck offered the opinion that when they use fibre glass instead of steel in bridges he will stop using steel also. Until then he uses both.
When I poured my garage floor they forgot the glass but I did have all the steel in. I was preoccupied and did not notice until we were finishing.

 

[Western]

All I have heard is you can do that with metal mixed into the cement. The owner of the local Cement company owner here did his new house this way, I guess to prove the point. I can't remmember what its called but I know it was like a very fine steel shred.

Every one else I know still uses rebar with fiber ( any kind) in the slab

 

[LBrown59]

Will I need rebar and wire in the slab?

The fiberglass replaces the wire & rebar hassle.

 

[Highbeam]

To answer your question on "cement or concrete" I can say that you are pouring concrete. An ingredient of the concrete is cement. You don't pour cement as cement is a powder.

I like steel in the concrete and the fibers are not a substitute. I also like to cut joints into the green concrete to control the cracks.

 

[Dargo]

I have poured well over a thousand yards of concrete at my place. I personally like the fibercrete along with regular rebar and 6 gauge steel matting. That seems to be the best combination for keeping the only cracks that appear to be hairline cracks. With only steel some of the cracks have gotten a little separation. Not enough to be able to fill with anything nor have any of the slabs moved vertically, but the cracks seem to be slightly larger than the concrete poured with the fiber in it. One area on a porch was poured with only fiber and no steel. I was not impressed and it was replaced.

I asked why they use fiber and not something akin to steel wool. I was told that anything like steel wool for fiber would be completely rusted and gone within a couple of years. So, based on the huge amount I have spent on concrete, and having had some extremely heavy traffic on my driveway, I'd say without a doubt to go with the fibercrete along with regular heavy gauge matting and rebar.

 

[Trainer]

Thanks for the replies.

 

[J_J]

Thanks for the replies.

Here is some more data for your comsideration.

Nycon - NyconPVA, High Performance Polyvinyl Alcohol Fibers

 

[EddieWalker]

Concrete is a mixture of Portland Cement, gravel and sand. You can add other ingrediants to the mixture for strenghth and drying time, but the basic ingrediants are always the same.

Portland Cement is named after the place in England where it was invented.

There are two things that you can guarantee with concrete, it will get hard and it will crack.

To minimize cracking, you can add fiberglass to it, but this does nothing to increase it's strength.

Rebar does this. Bigger rebar and more of it will give you more strength. A higher ratio of Portland Cement will also increase the strength of the concrete. Less water in the mixture will give you stronger concrete then a wet mixture. The less water the better. Slow dying time will add strength to concrete. If it's really hot out, the concrete will cure faster then is should, and you will lose strength and increase the amount of cracks.

Adding fiberglass will help to a certain degree, but doing this instead of using rebar is not something that I would do for anything that I owned.

Eddie

 

[schmism]

fiberglass is often used on slury pump projects, were forming rigid rebar would be especially complex and expensive. were as you simply pump the concrete inplace and it already has its reinforcement included.

guy driving the truck offered the opinion that when they use fibre glass instead of steel in bridges he will stop using steel also

Rebar in bridges is load carrying part of the structure. Simply adding mesh to flat work to prevent cracking due to thermal movement has little to do with adding steel reinforcement to carry load.