Concrete driveway on a slope - poly membrane?

[bozzle]

Hi,
I am laying a drive which is about 5m wide and 7m long and had planned to lay in 2.4m strips across the slope. No problem with first strip as it is nearly flat (slope of 1: 100) but was surprised at how much water ran off when the surface was tamped/raked with a piece of 3*2

On next section the slope is 1 in 20. and I am a bit concerned I may have problems with concrete slumping/running over the side. Was planning on installing membrane beneath slab but is this wise as I imagine it will help the concrete move. ?

Current mix was 12 litres water to 25kg of cement with plasticiser added. (added to 42 litres of dry all in ballast) Can I use less water to make it stiffer ?

Could lay it up/down slope but this will make access tricky
Any advice would be much appreciated.

 

[noseall]

why bother with polythene?

 

[Deluks]

why bother with polythene?

Nose, my thoughts here too, can you shed some more light on this for me please. Cheers

 

[noseall]

i imagined the coal chute to be attached to the building, hence the dpm.

 

[Deluks]

I'll bump the original thread back up, I'm still a bit

 

[bozzle]

I was planning to use a poly membrane as its recomended on the pavingexpert website

 

[JohnD]

Does it say "membrane" or does it say "polythene membrane"?