Testing Oversized Fill

[charlieroc]

I am about to start the monitoring and testing (if possible to test) of a 40,000 cubic yard embankment project. Specs call for embankment material to be 3 inch minus and well-graded. Contractor is crushing boulders to 3 inch minus material which has about 40% to 60% retained on the 3/4" sieve. Can not use ASTM D 1557 proctor because of amount retained on 3/4" sieve. Can field density testing be performed and if so, what proctor method should I use? If no testing is possible, is visual observation enough to keep me out of legal trouble?

 

[PSlem]

The Atlanta airport just got 8 million CY of oversized fill. I heard a speech by one of the engineers and they based testing on a report done by Army COE. Hopefully you can track it from there. I'll try to add engineer's name and co. Fri.

The optimist sees the glass as half full. The pessimist sees the glass as half empty. The engineer see the glass as too big.

 

[jdonville]

charlieroc,

Based on a quick Google search, it appears that the company who performed the materials testing (or was overall responsible) is CERM (

http://www.cerm.com).

The following item is taken directly from their website:

-----

(

http://www.cerm.com/news/view.asp?id=106)

Headline for 4/21/2005

C.E.R.M. Nears Completion of Hartsfield Jackson Fifth Runway Project

Atlanta, GA, April 20, 2005 – Work on the construction site of the new Hartsfield Jackson Atlanta International Airport 5th Runway is nearing completion.

C.E.R.M. was awarded the project in 2002 providing quality control, environmental compliance, construction material testing, geotechnical engineering and construction services for 5R Contractors, LLC, a consortium of several companies. Delta Airlines officials have said that without the additional runway in place, travelers at Hartsfield Jackson would be delayed as much as 15 minutes by this year, costing the company about $5 million each day.

-----

Hope this helps.

Jeff


Jeffrey T. Donville, PE
TTL Associates, Inc.

http://www.ttlassoc.com

 

[PSlem]

The testing co. was ATC Associates. John Lawrence did the speech.

The optimist sees the glass as half full. The pessimist sees the glass as half empty. The engineer see the glass as too big.

 

[jdonville]

charlieroc,

After digging through some of the USACE Engineering and Design Manuals, USACE does propose a correction for oversized particles in EM 1110-2-1911 (available for free download from USACE - just Google the designation). Reference is also made to the USBR Earth Manual. Unfortunately, the rapid test referenced in the Earth Manual is in Volume 2 - which I cannot locate online.

ATC's website claims that they proposed a rapid process that estimated the number of compaction passes required to minimize futher settlements. I used to do something similar back in my earthfill dam construction observation life:

Run a series of nuclear tests at the same location and plot the dry density vs # of passes. Eventually, this curve becomes flat (no more to be gained from additional compactive effort). The number of passes required to maximally compact the material can be read off the curve and verified periodically for accuracy at other locations. It doesn't tell you if you are making the proctor target, however.

USACE EM 1110-2-1911 also indicates that the maximum particle size is related to the mold size used. The bigger the mold, the bigger particle size can be accomodated. The USACE manual indicates that for 2-inch maximum particle size, a 12-inch diameter mold would be required. So if you really wanted to do a proctor (standard or modified), you would just need to get a special mold made and ensure that the compactive energy used was appropriate to the geometry of the sample.

Jeff


Jeffrey T. Donville, PE
TTL Associates, Inc.

http://www.ttlassoc.com

 

[PSlem]

i remember their mold was about 4'

The optimist sees the glass as half full. The pessimist sees the glass as half empty. The engineer see the glass as too big.

 

[charlieroc]

Thanks for the info. EM 1110-2-1906 is for 2 inch minus material which is actually helpfull for another project I have. I am still looking for an acceptable procedure for 3" minus material.

 

[BigH]

Just as a practical point to consider - when you say 3 inch, this means minimum diamter/width of 3 inches. Some aggreagate, say crushed, have elongation ratios of 2 to 3 so that, in fact one of the aggregates dimensions can be as large as 6 to 8 inches. This requires, in my view, judgment on "adjusting" the sample so that such outliers do not influence unduly your test results. You should be testing a representative sample and a few outliers shouldn't, in my view, modify the real test values. Given this, I would think that a larger 6 inch mould should be considered. Need, though, to consider the energy per layer and number of tampings per layer. Not always easy especially if others haven't done it for you by standards, etc.

Isn't it amazing how "everyone" is an expert on compaction, yet it is always the longest chapters in the books and raises the most questions?

 

[charlieroc]

Big H- Of course when you say 3 inch minus that means the material needs to fit thru a 3 inch sieve and you will likely have an occasional piece that is 2.99" x 4". Just like when you do a 1557 proctor and the 3/4 inch sieve will allow an occasional piece that is .74 inches by 1 inch in size...this is ok.

The EM 1110-2-1906 calls for a 12" diameter mold that is 12 inches deep.

I still have not found a 3" minus "proctor" test and at this point I am thinking along the lines that was suggested earlier about compacting each lift until the density will no longer increase with another pass. Count the number of passes it takes to achieve "maximum compaction" and then compact each lift with that number of passes. I just wish a respectable authority like the Corp or ASTM had a method to follow so the attorneys do not have a field day on me later.

 

[PSlem]

Call ATE. I think the COE publication in question went to 12". But this is not my specialty. I was picking up Cont. Ed. credits.

The optimist sees the glass as half full. The pessimist sees the glass as half empty. The engineer see the glass as too big.

 

[eric1037]

Check out a paper by Guanqing Feng & Stanley J. Vitton entitled, "Laboratory Determination of Compaction Criteria for Rockfill Material Embankments." from the Proceedings of the Fourteenth International Conference on Soil Mechanics and Foundation Engineering, Hamburg/6-12 September 1997.

They discuss and compare three different methods of modelling rock fill material.

Stan Vitton is a professor at Michigan Technological University. He would probably be happy to talk your ear off on this subject.

http://www.cee.mtu.edu/people/sjv.html

 

[CarlB]

Probably the "most proper" way is to use the vibratory table, ASTM D4253:

http://www.astm.org/cgi-bin/SoftCart.exe/DATABASE.CART/REDLINE_PAGES/D4253.htm?E+mystore

AASHTO T180D has been used for some time to make corrections for oversized particles. A link here:

http://cms.transportation.org/?siteid=56&pageid=1311