Actually, the thread title and the question are different. I answered the question before, but perhaps you want to know the appropriate method for determining the moisture-density relationship (Proctor). 30% oversize is a lot. Replacement is the usual method under ASTM D1557 or AASHTO T180. Check with your state DOT (assuming you are in the US), as they sometimes supplement methods for local conditions.
I am working on a project where the contractor is proposing to use a material with oversize rocks (80%)and the material meets the project fill specification. However all fill material used on-site has to be compacted to 95 % of MDD (ASTM D 1557)as per the project fill placement criteria. So, the question is how to verify the compaction or first how to determine the MDD? We are not equipped to determine the MDD as per DOT specified method.
It would see if one really wantst to do this as near correct as possible, he would compact the would sample, not sieving out the coarse parts, but compact to the same energy per cubic foot as the standard.
Digging out the old Bureau of Reclamations standards will show one hoe it can be done, but it means a lot of work to develop the equipment.
Otherwise accept a method of compaction on the job as to what will be acceptable, such as 5 passes of a certain roller on a given thickness layer, etc.
OG...I agree that the better way is to do, say 5 passes of a compactor, then take the in-place density. Let that be the "standard" for comparison for compaction. With that I would require 100 percent compaction.
The alternative is to try the various replacement methods and crushing methods proposed in ASTM and AASHTO.
To be practical, the EOR should be consulted to see if he can accept another compaction criterion.
For rock fill, we recently placed it and did 2, 4, 6, 8 and 10 passes of the heavy vibratory compactor. We then plotted the "settlement" vs each set of passes to get a curve - then, as suggested in article "Rock Fill" - one of four articles (can't remember URL off hand), we chose the number of passes that achieved > 80% of the settlement. We also rolled in both directions.
What is the practical sense of trying to achieve a compaction of material that doesn't meet the type of material presumed in the standard test? Why was it even specified if the EOR put such a range on the acceptable fill materials? Seems like the spec was a standard used without thinking . . .
