FAA Gradation Requirements after compaction of P-209

[DDBPE]

On a recent project, the P209 met specs for material properties and gradation at the plant. Then after 100% compaction the specs require the gradation sample to be taken from the in-place compacted material.
The test at the plant were in spec, however, the test after compaction resulted in finer material than allowed on the #200 sieve.
Now there is a possibility of a penalty for this material, although they do not have a way to determine this by spec (PWL).
I know from working in several states and for different agencies, most take gradation test prior to compaction either at the plant during shipping or after it is placed but before compaction.
As most of us know material degrades when it is compacted, does anyone have any thoughts or studies to help our position.

 

[cvg]

well, checking gradation after compaction is definitely not the standard procedure, but presumably the contractor read the spec prior to signing the contract? and should have objected to it prior to now.

http://www.faa.gov/airports/engineering/construction_standards/

the standard FAA spec does not include this requirement. Perhaps you can ask the designer if he has any studies showing the predicted breakdown of the material due to placing and compaction and ask why there is no allowance in the specs for this breakdown.

 

[Dozerman56]

How many samples were taken for after compaction testing? Did they all fail? Were there hardness specifications for this material? If so, was testing done before placement? Was the source of the material on any kind of pre-approved list the owner may have? Did the supplier's proposal state materials would meet project specifications?

 

[DDBPE]

Thanks for the comments.

cvg - we did ask if they could predict the amount of breakdown and they could not answer the question. The problem is the spec requires the material at the plant to be within spec and also after compaction. Our argument/discussion was how do we make the product out of spec at the plant to be in spec ofter compaction.

Dozerman - 12 samples were taken and 11 failed the #200 sieve and a few on the #30 sieve by both QA and QC testing. There were quality specs for hardness, F&E, sodium sulfate and it passed and was approved by the engineer. Quality testing was done prior to placement. This material was not on a pre-approved list and the quarry does supply materials to the state and is on there list. The suppliers proposal was to provide P-209 material meeting specs.

This was an accelerated project, after the 12 samples were taken, two days later we started paving. We had our density and the plant results showing the P-209 was within spec at the plant. It took the Engineer 2 weeks to get gradation results to us and by that time, we had finished the 14 inches of P-401 asphalt.

One other thing, we did a test for the engineer after we received the failing tests to show the material breaks down on a shoulder we had to construct. We tested a sample at the quarry, then after placement, and a final one after compaction. The quarry and placement sample were within spec and the gradations were similar, however, the #30 and #200 sieve failed again after compaction.