Limestone vs Granite Roadstone

[tscalfa]

I'm putting down roadstone as a temporary (12 months ish) drive surface. Is there much difference between the durability of limestone or granite? The drive does have quite a steep slope in places 1:10 so I need it to bind together well.

[tscalfa]

Any advice please?

[RGG]

My understanding and limited experience -

First, I don't know what gauge you are considering - 20mm?

Granite as stone is impermeable, so it won't breakdown.

I am not referring to the surface being impermeable - it will be permeable.

Limestone depending on the quarry source will be more susceptible to rainfall to breaking down and going a bit mushy - sorry for the technical terms :
But it will bind very well.

I think either will do the job - I was happy with the limestone because it bound very well.

[tscalfa]

RGG said:

My understanding and limited experience -

First, I don't know what gauge you are considering - 20mm?

Granite as stone is impermeable, so it won't breakdown.

I am not referring to the surface being impermeable - it will be permeable.

Limestone depending on the quarry source will be more susceptible to rainfall to breaking down and going a bit mushy - sorry for the technical terms :
But it will bind very well.

I think either will do the job - I was happy with the limestone because it bound very well.

Thanks for the advice, I'm looking at putting down about 100mm.

[RGG]

tscalfa said:

RGG said:

My understanding and limited experience -

First, I don't know what gauge you are considering - 20mm?

Granite as stone is impermeable, so it won't breakdown.

I am not referring to the surface being impermeable - it will be permeable.

Limestone depending on the quarry source will be more susceptible to rainfall to breaking down and going a bit mushy - sorry for the technical terms :
But it will bind very well.

I think either will do the job - I was happy with the limestone because it bound very well.

Thanks for the advice, I'm looking at putting down about 100mm.

The size of stone "20mm" is referring to the gauge of the stone - it's usually goes - dust - 6mm - 10mm -20mm

I'm guessing your 100mm is referring to the bed depth - which is appropriate for your needs, I believe -

[TA14]

The granite won't bind together whereas the limestone forms a natural cement. 20 to dust or 38 (1.5") to dust should be fine for you. Put a crown on the drive.

[m3jappa]

Are you talking about type 1 here? I assume so.

Im surprised you've got a choice between as here it is what it is. There is no difference in my experience. Although you can get loads which are a bit stoney or a bit dusty so does depend on the place selling the stuff which isn't easy to really determine. just have to try and keep some dusty stuff for the top.

wet it up when you compact it and it will go very tight.

[Tant]

Hopefully I can help...spent 13 years working with Tarmac as a quarry manager and did a degree in quarry engineering and road surfacing, albeit quite a long time ago...great company and job back then.

Anyway, it sounds like you need something like a type 1 type material that will bind together well as it is a very open graded material...has a wide range of sizes of different bits in in from about 40mm down to dust. This helps it bind together well as the small bits fill in the voids in between the big bits.

It's not worth importing granite if all of the suppliers around you are supplying limestone, so say if you live in Yorkshire or Derbyshire, limestone will be relatively easy and inexpensive to get delivered in bulk, but it would be expensive in, say Scotland as the haulage would be a lot

Vice versa, Granite more plentiful in Scotland, Leicestershire and (sort of granite) Northumberland.

If it's just going to make a temporary track limestone should be hard enough...granite only normally comes into play in the upper surfaces of paved/tarmaced roads where skid resistance and resistance to polishing are much higher in granites than in limestone.

You might want to consider finding a local source of tar planings...this is the material planed from the roads when carriageways are resurfaced and you often see them in heaps in laybys near roadworks...these can be very cost effective and make an excellent well bound temporary road surface when you've compacted them down a bit.

Might want to lay type one down first to make a decent bed, then put tar planings on top for a smoother and less muddy surface in wet weather

Hope that helps
Tant

[loudlashadjuster]

Tant said:

Hopefully I can help...spent 13 years working with Tarmac as a quarry manager and did a degree in quarry engineering and road surfacing, albeit quite a long time ago...great company and job back then.

Anyway, it sounds like you need something like a type 1 type material that will bind together well as it is a very open graded material...has a wide range of sizes of different bits in in from about 40mm down to dust. This helps it bind together well as the small bits fill in the voids in between the big bits.

It's not worth importing granite if all of the suppliers around you are supplying limestone, so say if you live in Yorkshire or Derbyshire, limestone will be relatively easy and inexpensive to get delivered in bulk, but it would be expensive in, say Scotland as the haulage would be a lot

Vice versa, Granite more plentiful in Scotland, Leicestershire and (sort of granite) Northumberland.

If it's just going to make a temporary track limestone should be hard enough...granite only normally comes into play in the upper surfaces of paved/tarmaced roads where skid resistance and resistance to polishing are much higher in granites than in limestone.

You might want to consider finding a local source of tar planings...this is the material planed from the roads when carriageways are resurfaced and you often see them in heaps in laybys near roadworks...these can be very cost effective and make an excellent well bound temporary road surface when you've compacted them down a bit.

Might want to lay type one down first to make a decent bed, then put tar planings on top for a smoother and less muddy surface in wet weather

Hope that helps
Tant

PH at its best. Chapeau!

[tscalfa]

Thanks for the advice everyone. I have got the choice of either limestone or granite depending on which supplier I use.