AC paving at Lip of Concrete Gutter 3

[BRL43]

I have a client that want his contracter to "fix" the AC paving that is currently 1" above the lip of gutter. The contractor says this is ok and that they leave the AC above the gutter lip on purpose. The Greenbook only talks about a 1/8" tolerance when matching new pavement to existing pavement. The Greenbook also repeats "the pavement shall be true to grade and cross section." None of our local standards deal with this issue. Thanks for the help.

Ben
PE, San Diego

 

[GeoPaveTraffic]

New pavement, asphalt or concrete, should be installed to meet existing grades. If the concrete gutter was in place prior to the asphalt being placed, then the asphalt should be installed to meet it. The contractor is somewhat correct, in that higher is better than lower in this case; but an inch is way too much. I would allow a quarter inch over relatively short distances, say 10 feet or so, but no more.

 

[theCorkster]

Ben:

Is the contractor figuring the subgrade and base beneath the AC is going to settle and bring this down? Unfortuantely, many pavement failures occur after the pavement section settles and becomes lower than the adjacent concrete - the water goes into the pavement base and subgrade. Unfortuantely, the 1 inch height will ravel and crumble long before the pavement settles 3/4 inch (hopefully it does not settle that much).

 

[civilman72]

Here in Colorado Rocky Mountains, it is common for pavers to purposely leave the asphalt higher than lip of gutter. I believe this is done for some of the same reasons listed above (settling of subgrade/basecourse and potential drainage infiltration between concrete and asphalt) and also to "protect" the lip of gutter from snow plow blades.

It does seem that a full one-inch rise is a little excessive, but, as previously stated, it is definitely better to be too high than too low.

 

[BigH]

Your standards may not say but what does the construction specification say? Tolerance on paving? Check out the specifications first.

 

[bothunter]

1/8 inch above lip of gutter is correct. This allows for water to exit the pavement and enter the flow line of the gutter.

If your compaction tests for the native soil and aggregate sections meet the specified standard, i.e., 95% relative compaction, then the 1" above the concrete lip is to high. Compaction is irrelative if this was an overlay of existing asphalt.

This creates an obvious hazard to "catching your toe" and causing a fall. Liability can be an issue here.

The solution is to lower the edge of asphalt to meet the 1/8 requirement. Again, 1/8 inch is optimal, with up to 1/2 inch maybe acceptable to allow for settling of the A/C over time.

There are propane indirect heaters that can accomplish the re-heating of the A/C in localized areas, thus making the A/C pliable again and then it's just a matter of workers raking away the excess and removing it and then re-compacting the A/C to seal it again.

The contractor probably did not figure removing asphalt into his bid, however, it seems the contractor gave you a "honest section" with the 1 inch above lip. Coring is also a quality control technique that will verify that specified standards have been met by the contractor.

 

[pshark]

Was the contractor paid by the in place weight or volume of the AC? If so I think he just made more money.

 

[oldestguy]

What are the fix alternatives?

What credit is given for the mistake?

I'd ask for a discount of 20 percent or more for the whole paving job, followed by tack coat of the gutter, then place one inch of surface course there after compaction.

The alternative to this is rip out all asphaltic concrete and build it to specs.

Leaving it "as is" is opening up the road owner to expensive law suites.

 

[blueoak]

Do you have a city inspector? If this is a public road they will make your client fix it. I agree with the problems of having the AC too high, but the liability will be why it is fixed. Oldestguy has a good point if it is a private road.