The Brew Cabin

Posted: **Tue Sep 17, 2013 10:34 pm**

As I understand when reinforcing the concrete for a new driveway I can either go for steel mesh or alternatively have special fibres added to the mix I would think that the mesh would be preferable but for the area needed (around 160sq metres) could prove quite expensive So I would like some guidance on just how effective the fibres are in strengthening the final result and whether is is worth doing or not The drive will mainly take light vehicles but with Heavy vehicle use around 3 - 4 times per year (eg Oil deliveries / Septic Tank emptying etc)

Also what about if the steel mesh were laid just in the part of the drive that takes the vehicle wheels (ie avoid the centre which never gets any weight on it This would cut down quite a bit on how much was needed

Thanks

Posted: **Thu Sep 19, 2013 10:47 am**

What do you mean by special fibres? Are you referring to polypropylene (normally monofilament) fibres or something else? If it's polypropylene fibres, they're really only suitable to replace crack control mesh. The latter, is usually A142 and should be placed somewhere near the surface of a slab (say 50mm cover for a 150mm thick slab) to do its job properly. All to often it's just trampled in after placing the concrete with size 10 boots ending up closer to the bottom of the slab resulting in surface cracking (particularly if the concrete is not cured properly). Polypropylene fibres also improve impact and abrasion resistance to a certain extent.

To withstand heavy loads such as hgv's, even if only infrequent use, it's personally better to use something like A393 mesh placed in the lower half of the slab. Concrete is strong in compression but relatively weak in tension (about one tenth) so steel is included in the tension zone (the lower section of the slab) to minimise cracking under load.

If your budget extends use both mesh and polypropylene fibres to ensure the concrete lasts a lifetime. Anything less increases the risk of cracking in the longer term. You may not be worried by a few cracks - it's obviously your choice.

It goes without saying that whatever you use, the concrete must be placed on a well compacted base such as 150mm of MOT Type 1. It's preferable to lay a separating polythene membrane between the base and the concrete. This allows the concrete to slide/slip during the cycles of contraction and expansion further minimising the occurrence of cracks.

For a domestic driveway to take light vehicles such as cars, you should use a PAV1 concrete (C30 air entrained), however, a PAV2 (C40 air entrained) is recommended when used by hgv's, particularly where a lot of turning is involved. With only infrequent use by hgv's you may get away with a properly constructed PAV1 or somewhere inbetween such a C35 air entrained - again it's you choice.

Posted: **Fri Sep 20, 2013 8:40 pm**

When I asked at Travis Perkins they quotes me for A142M mesh I hadn't realised that there were different types of mesh I will look into this

Can I take it from your answer that only placing the mesh in the wheel tracks rather than covering the whole width of the drive would be a waste of time or is it still worth it

Thanks

Posted: **Fri Sep 20, 2013 8:48 pm**

Mesh in the tyre tracks is a waste of time and money for little gain,A142mesh is ok or A252 is the stuff

MSH

Edited By msh paving on 1379706562

Posted: **Fri Sep 20, 2013 8:52 pm**

if you are buying mesh, you will be better of going to a reinforcement steel supplier, probilly save 1\3 and the sheets will be 2.4x4.8m MSH

Posted: **Fri Sep 20, 2013 9:08 pm**

I agree with msh on both his posts. A252 would be best in your case in view of the occasional hgv (A393 belt and braces).

Posted: **Sat Sep 21, 2013 4:14 pm**

msh paving wrote:if you are buying mesh, you will be better of going to a reinforcement steel supplier, probilly save 1\3 and the sheets will be 2.4x4.8m MSH

Any suggestions for North Notts region

Thanks

Posted: **Sat Sep 21, 2013 6:18 pm**

this is who i deal with, theY deliver all over
the roe group

call peterborough office ask for william ,usually in office after 10am he will give you best price MSH

Posted: **Sun Sep 22, 2013 11:48 am**

remember you need 40X teh diameter of the rebar for overlap

so 40 x 8mm for 252 = 320mm overlap or most ppl do two squares so you need to allow for the overlap where ever it connects to another sheet

Posted: **Mon Sep 23, 2013 10:51 am**

msh paving wrote:this is who i deal with, theY deliver all over
the roe group

call peterborough office ask for william ,usually in office after 10am he will give you best price MSH

Thanks for this link I did make contact very useful

My drive is approx 3.2m x 60m and on a steepish slope

I would apperciate advice on the best way to lay these sheets (2.4m x 4.8m) ie by length or width and how to deal with overlapping etc

Thanks

Posted: **Mon Sep 23, 2013 7:39 pm**

get the merchant size mesh 3.6 mx2.0m from travis etc then

cut a bit off one end then 60m /1.8 = 33.3 so 34 sheets

http://www.ebay.co.uk/itm....3a55020

then you want some of these

http://www.ebay.co.uk/itm....111ed08

i buy them in bags of 1000s for a lot less than ^ that price though

Posted: **Mon Sep 23, 2013 8:48 pm**

last time i got A252 merchant size from buliders merchant it was same price as 2.4/4.8 from the roe group, if price is a issue this is something to think on, also 1.2m dia. deck circles are far cheaper and easier to use than the plastic things.again chek on price
but that is my way, others may have different views

MSH

Posted: **Tue Sep 24, 2013 9:14 pm**

"1.2m dia. deck circles"

what are these?

Posted: **Wed Sep 25, 2013 6:36 am**

http://www.theroegroup.com/pdf/catalogue.pdf
page 7 circular deck spacers, or deck chairs, so much quicker than plastic things, lay them down mesh on top job done

MSH

Posted: **Wed Sep 25, 2013 6:17 pm**

We use the triangular shaped ones but not seen the circular ones,

The plastic ones are really easy as they just push on in 50mm or 40mm spacings

But those tying guns I bought have been amazing used every day best thing I ever bought

The Brew Cabin

Reinforcing a concrete drive - Concrete drive