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blue stone compaction

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unpluged

Mechanical
Sep 8, 2007
9
During construction of a 2000 ft. road I ordered my driver to put ledge pack over a compacted 2in.stone base.

When I returned the driver had used 1/2in.blue stone that had no binder.
Has anyone suggestions on how I can compact this for light traffic?
Can I leave it and run the roller with water and get it to hold up to winter plowing etc?
I was reading the post on thread158-156635 however I did not see any advice on this type of question.
 
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Clean stone is tricky because it can't be tested. I generally use it in trenches that contain water so there's no binder that might get oversaturated. What they'll tell you in the field is that clean stone like that goes in at 100%, same with pea gravel. I think the point is to have a sturdy base that will stand up to a break-down roller over your asphalt. One problem I can maybe see is that you might not get your nice smooth asphalt surface if there's voids for the asphalt to creep into. Have you thought about distributing some sand over the stone just to fill in the voids? I think the stabilty of the clean stone would be ok, given it's made from crushed material and has an angular shape to hold the structure, probably at least 3 fracture faces per stone. But again, they usually use an open gradation.
 
Single sized coarse stone has some advantages as well as disadvantages.

An advantage where there is to be a rigid pavement over it is that under saturated conditions the fines (if there were any) are not pumped out through the pavement joints or is not forced back under the slab "behind" and a "faulting" does not occur. This faulting is a common problem in the states where a well graded base course is used. Many a state highway department is plagued with this situation.

A disadvantage is the fact that on a wet, soft subgrade, the soft mud can migrate into the voids and allow frost action to take place sometimes to te extend that the support of the base course is lost in spring thaw periods. However, with a sufficiently thick layer of base course this seems to work ok. I know of two cities that have a base course spec that calls for this single-size rock material under rigid pavement and it seems to "get by".

So, if your layer is thick enough for your traffic, it probably will work. I'd roll it with effort and hope for the best, especially with light traffic. You may lose some with snow plowieng, but that is doubtful.
 
dirtsqueezer,oldestguy and all Thanks for such help
The blue stone is now compacted and seems like it will still need a binder of some type.
It was not to be paved.
If I can I will suggest the paving, but it is unlikely, as funding has been reduced sharply.
AS we all know a funding cut means the fun will end to when spring thaw shows up.
A pleasure to read your reply.

Sometimes learning comes between a rock and hard head!
 
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