Compacting hard core.

[User]

 

[smokeysmoo]

@Fnaar

 

[Dave 123]

What are you doing on top of the compacted hardcore?

 

[Rooster1]

Is the question how much above ground level (for the aggregate) ?
or how much above your soil which you've dug out (for the aggregate) ?

 

[BoldonLad]

I am no civil engineer, but, I would have thought the answer is, as much aggregate as you need, for intended load bearing, and, adjust paving height by varying depth of sand, under paving. Since sand depth easier to control than compacted aggregate depth? Have I passed my NVQ1 in paving?

 

[Levo-Lon]

The slabs will need a 25-50 mm bed be it wet or dry mix.
So if you have 25 30 mm plus slab you will be fine.
Some hardcore rams better than others with a plate.
I,e M,O,T is the best and 50mm to dust limestone is not so good.

Mot is also frost proof , limestone isn't

 

[Deleted member 26715]

[QUOTE 5216520, member: 9609"]neither. I can't really think how to ask what I'm wanting to know.[/QUOTE]I know what you want to know, but don't know the answer as it will depend on the compactness of the hardcore, the weight of the wacker & possibly the vibrations per minute, but I'd start at 25mm & hope for the best, you're best to be lower & come up with sharp sand & gobbo.

 

[Rooster1]

I didn't get much of a drop when I compacted the hardcore for the patio I layed. However the maths I did for depth of digging, amount of hardcore and thickness of slabs all worked out well. Unfortunately it looks crap because my levels were slightly out. The wife likes it though.

 

[Dave 123]

If it’s only foot traffic then not too much.

If it’s HGV’s then you might want to put lots down and ram it like crazy!

 

[Levo-Lon]

I must be on ignore?

I've be doing paths and drives for decades..it will do pretty much as I posted..

 

[I like Skol]

The answer is, stop being a tightwad and hire the wacker for long enough to do the job properly!

No need to thank me

 

[nickyboy]

I used to work for a company that makes compaction plates (Wacker was our main competitor)

It very much depends on the nature of the hard core you're putting down and your method of putting it down. Too many variables to give definitive advice. What you should do is prepare an area with variable depth hardcore (say from 5in deep to 8in deep) and then quickly compact it with the plate. That will tell you what depth gives you the 4in result.

To reduce your plate time you should at least cover the whole area with the minimum 5in. Then top up based on your experiment

 

[Levo-Lon]

m.o.t type 1 , is a granite hard-core which you should be able to buy locally.
its usually 40mm to dust and far better for levelling and getting a tighter and more accurate level.
its only a few quid a ton more than limestone.
you'll be fine with inch and a half of bed. 25mm- 50mm sand cement mix is perfect.

use a string line set to your desired finish level then just dip with a tape so you have at least 60mm-70mm before compaction.
you should get your desired bed depth with 3- 4 passes with the plate.

nice thing with mot is its really easy to adjust the level.

you should get appropriately 8-9 square m2 with a 0.9 cubic m2 bag of hardcore at 100mm depth.


hth