What fibres are used in fibre reinforced cement?

[nuzuki]

I have quite alot of fibreglass matting left over from old projects. I was hoping this is the stuff they use in fibre reinforced cement/concrete? If so.... I'll get my scissors out

Thanks for your help

 

[JohnD]

I recall attempts were made years ago to make fibreglass reinforced concrete, but the ordinary glassfibre degrades in the alkaline mixture. Because the individual filaments are so thin, erosion of the surface takes them to practically nothing.

You can get fibres to mix into concrete now, I don't know what they are made of, but it's different.

 

[bernardgreen]

From one manufacturer

http://www.cemex.co.uk/fibre-concrete.aspx

there are other suppliers

 

[^woody^]

Complete waste of time and effort

 

[nuzuki]

I saw some of these fibres in wickes a while back and it looked like a plastic bag cut into pieces. Reading that cemex site says they are Polypropylene which didnt look very fibre-y. It was just a fleeting thought more out of interest than something i'll actually do.

Cheers for the replies

 

[tomfe]

You can however get GFRC which is glass fiber reinforced concrete. It's very thick so it needs a super plasticiser.

 

[nuzuki]

I think poly propylene is found in rope and tarpaulins for anyone wanting to get their scissors out

 

[^woody^]

You do realise that the fibres do not reinforce the screed to make it any stronger, but just control initial shrinkage cracking.

 

[nuzuki]

Ah thats interesting, thanks Woody. I was suprised at the small quantity wickes sold of these reinforcing fibres and thought what use if any would that be. I think it was around £4.99 a bag. Might be ok for a garden step project but not at all economically viable for a larger project. I will stick to reinforced mesh, rebar or a stonger mix.