[Talk-us] Gravel roads and surface tags in the US

[Max Erickson]

>I grew up in an area with these kinds of roads and I don't think
>they're technically compacted.  The gravel, which is crushed
>limerstone, is laid down and due to its chemical properties creates a
>smooth surface after several months of traffic.

Having read about this some since Tobey mentioned it on Slack, the
compaction is often meant to come from traffic.

In the Midwest the material is often from local "gravel pits" which
are glacial material, so a mix of sand and rounded stone. I think they
do some sorting and remixing of the material before using it for road
surface construction, and they definitely add clay as a binder.

I think the use of clean stone (the wiki gravel) is more common for
ornamental driveways than for any road meant to bear much traffic.
Apparently part of the issue is that there aren't many built roads in
the UK (and Europe in general) that aren't sealed.


Max