Concrete drive - Re-inforcing & visqueen

[DNgroundworks]

Hi all Just a few questions.

1. Is it absolutley neccesary to use visqueen under exterior concrete, as i have pulled quite a few up and seen many put down and never seen visqueen used yet, i take it, its only benificial in very dry weather?

2. Also i have priced a job ( access to a field, cars everyday and about 2 tractors a year ) and the customer has specified he would like me to use 200mm concrete with no reinforcing mesh, i would normally of used 150mm with reinforcing, your thoughts?

p.s Great site by the way, being only 20, this site is an invaluable aid to me, good job.

[Dave_L]

1) Yes, otherwise the ground will suck the moisture out from the 'crete too quickly

2) Mesh would be ideal, but aslong as there are no heavies going over it, I think you'd be OK with 200mm.

[GB_Groundworks]

but a tractor pulling a full trailer loaded with bales or muck and your looking at the 30 ton mark, i'd be sticking some a142 in there as well as some fibers,

i'm only 26 haha helping drop the average age down all these oldies on here like dave :p (p.s i have know idea how old dave is, but his sage like advice leads me to believe he has many years of wisdon under his belt)

[DNgroundworks]

ok, so suction will still occur even if it has p*ssed it down every day for a month?, weather is crap up here apart from last week!

Only 26? seem to have your setup sorted how old were you when you started out? Im only doing domestic projects and minor public and civil works, nothing major.
Where you based?

[DNgroundworks]

Also when taking up old farm yards and the like which are in good condition been down 20 years and no cracks, why all of a sudden do we need all this other additional reinforcement when back then it was just plain conc and no mesh??

Will a well compacted sub-base, and good quality 200mm high grade concrete not suffice?

Do people over-egineer just to cover themselves?

[seanandruby]

maybe the reason you have seen many concrete drives pulled up is because there was'nt any dpc, or reinforcing used. and if you have seen many slabs laid without the above then RAWHIDE must be doing a re-run. :;): visquin not only protects the underside of the slab from chemicals such as salts it stops it drying out to fast and causing cracks. the reinforcing will do what it says on the packet. a lot older and hopefully wiser
"learning is not attained by chance, it must be sort for with ardor and attended to with diligence."

[GB_Groundworks]

ok the question about mesh etc - people tend to over engineer to cover themselves (i.e its better to do a good job than skimp and do a bad job) and because there are laid out standards and build regs etc that in the worst case scenario in court etc you can say that you constructed following guidelines that any reasonable contractor would have done. concrete is very strong in compression but not in tension so the rebar is in there to give it tensile strength.

200mm of c30 or c35 well may suffice but an engineer is more likely to specify it with mesh in, its likely that 20 years ago they should have put mesh but didn't

my dad runs a mid sized house building company i worked for him since i could lift a spade, had 2 years gap to go and programme unix servers in munich but came back and set up ground working a year and half ago, and as they say rest is history. we are based in the high peak, south east of manchester.

[Dave_L]

but a tractor pulling a full trailer loaded with bales or muck and your looking at the 30 ton mark,

But that would be overloaded! 24.3t is the limit iirc??

[Dave_L]

i'm only 26 haha helping drop the average age down all these oldies on here like dave :p (p.s i have know idea how old dave is, but his sage like advice leads me to believe he has many years of wisdon under his belt)

and I'm *only* 36!

[msh paving]

Farmers do as they like when it comes to tractors,and carring weight...... :p

[GB_Groundworks]

but a tractor pulling a full trailer loaded with bales or muck and your looking at the 30 ton mark,

But that would be overloaded! 24.3t is the limit iirc??

i think the 24 ton limit only applies to running them on a normal license not on hgv or with air brakes and operators license. if they are taxed as commercial vehicles running on white diesel and high enough top speed they are even allowed on motorways. although finding detailed information about the traffic regulation is hard work. i've seen fastracs (9 ton) pulling 20 ton dump trailers round here looking at 30 tons all in.

plus this only applies to road use, if the field entrance is off the yard then they could be carrying what ever weight they can get in the trailer

[DNgroundworks]

a lot older and hopefully wiser
"learning is not attained by chance, it must be sort for with ardor and attended to with diligence."

Well that why im on here, and thats why i asked the question!

"if you dont ask youll never know"

[lutonlagerlout]

subbase is a very important part of any road/path,150mm of well compacted type 1 on good subgrade ,with 150mm c25 concrete with mesh will last the test of time
better to over engineer than under
200MM concrete sounds way over the top
LLL

[GB_Groundworks]

this is what we use for farm yards

http://www.cemex.co.uk/re/pdf/ReadyMix_Farmpave.pdf

drawing from pdf



they are saying 200mm concrete and subbase in layers of 225mm, although understandably they want to sell more concrete haha.

[Dave_L]

Farmpave - resistant to gallons of hit and miss!!



Edited By lutonlagerlout on 1229387457