On Fri, 25 Jun 2010 19:41:03 GMT, "l, not -l" > wrote:

>
>On 25-Jun-2010, Kate Connally > wrote:
>
>> Sound like something on the menu at your local
>> pub?
>>
>> That's what comes to my mind every time I see these
>> signs along the roads here in the Pittsburgh countryside.
>> Maybe pita chips and seasoned olive oil?
>>
>> No, it's a weird local (as far as I know) phenomenon
>> where in the summer many of the back roads sport these
>> signs. It means the county (or whoever is in charge of
>> these roads) is going to put gravel chips and oil on the
>> roads. I guess it's supposed to do something to keep
>> them in good repair, but I've always found it odd.
>
>The process is called sealcoating and is used to extend the life of asphalt
>pavement. The idea is to fill cracks and voids with a tar-like substance
>and small gravel. In climates subject to freezing, one of the major
>destroyers of pavement is ice. Water fills cracks in the asphalt paving,
>then expands as it freezes make the crack bigger and pushing up the
>surrounding pavement; freeze/thaw cycles breakdown the paving until potholes
>form and traffic hitting the hole edges does even more damage.
>
>Sealcoating fills the cracks with aslphalt and gravel, reducing or
>eliminating the damage of freeze/thaw cycles. If it is being done in
>places not subject to freeze/thaw, I have no idea why they would do it.

It's called chip and seal or chipseal. Not seal-coating. I'm not
going to google more but I think some roads are never actually paved
but made by the chipseal process.

http://www.performancepavingltd.com/chipseal.html

http://www.dot.state.oh.us/districts...factsheet.aspx


Lou