Road Question: Utility Patch, Concrete under Asphalt?

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aaronhirsch

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Hi. I have a quick question on acceptable substitute for a road restoration method and I would greatly appreciate any feedback on this problem.

See the attached county specification for a utility patch. We have a situation where we need to restore a section of a residential road in a small town. We made a cut in the road to install water and sewer for a house and we are responsible for its restoration. When the cut was made a layer of concrete was found under the asphalt; presumably an old utility patch. The county inspectors told us to add a 4" layer of base asphalt instead of "matching existing condition". If we were to match the existing condition, we would have to match the concrete layer which is more than three times the price. Unfortunately the small town's engineer who has no particular background road engineering wants us to match the existing condition and the town overrules the county in this matter. I am trying to make a technical argument that the county's method is acceptable. My question is: is the county's method acceptable? Is it a better method than using the concrete/asphalt combo? Who is technically correct here?

Here's the statement from the town's engineer: “If the base layer of the existing roadway is concrete, then the base for the widened section must also be concrete. If the existing base of any section of the circle is asphalt, then the new base should also be asphalt. The reason for this is that both materials will react differently to the weight of vehicles, expansion and contraction from temperature differences, frost heaves, and long term settlement. Within five years, the un-matched base materials will telescope through, and appear on the surface as bumps, cracks, and uneven surfaces."

Thanks for any info you can provide!

Aaron

Utility Patch Spec.jpg

 
I don't know if you are going to find a technical reason. We had a job that we discovered had concrete base and they allowed us to use superpave. Which was much cheaper, it will cause issues in the future. Concrete based roads are very stiff, superpave is flexible, if a truck comes through a lot and hits your patch it will make the patch fail.
 
Hi Aaron,
This is a complex issue. While it's understandable that the town engineer wants to maintain consistency in the road's base material, it might not be practical to match the concrete layer if it's significantly more expensive.
 
Hi Aaron,
This is a complex issue. While it's understandable that the town engineer wants to maintain consistency in the road's base material, it might not be practical to match the concrete layer if it's significantly more expensive.
The county's method of adding a 4" base asphalt is likely an acceptable substitute and may even be preferable for reasons such as durability and cost-effectiveness. Ultimately, it may be best to consult with a road engineering expert like Asphalt Services In Akron OH - PAVE ALL Asphalt Company or the county's road department for a final recommendation. Good luck with the restoration!
 
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