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Dispute Resolution/Improper Compaction Testing 4

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Captain37

Civil/Environmental
Dec 30, 2008
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Hello all, I am a heavy/highway contractor and I am preparing a DRB Response. My claim is that the owner project representative improperly tested compaction on embankment we were building in order to cause false negatives (failures). This caused my co. to incur considerable monetary damage. I know that procedure is critical when using a moisture density gauge, but my question is: How critical??? Note: The inspector did not perform proctors on half of the tests taken when the owners specifications outline the specific procedure to follow.....??? Thanks everyone!
 
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There are ASTM and perhaps AASHTO (for your site) standards that apply to this form of testing. Before you go too far, I'd bring on board an experienced geotechnical engineer (even though you may be well experienced) and develops a program as if you were going into court It may be a good idea to bring on a lawyer, but be sure he (she) is construction experienced.

I suspect that a nuke gage was used on the job (the lazy way to get a lot of test data) and many swear by that. However, the standards tell how you calibrate that against known acceptable testing methods to be sure the work is done right.

There is another current thread getting extensive remarks (It may be in the "testing" room). They deal with this general subject and there are several experts there.

The only thing I would add about using the sand-cone method for calibration of the nuke, would be that the sand cone size has to be the large size (I believe it is 8" diameter), since that method also can have errors and you need a goodly large test sample to minimize those errors.

In my experience (I'm 81 years old and still working some), I was one of the first to use nuclear methods at Cornell University in grad school where it was developed in 1954,and I followed that through with equipment from NuclearChicago and now Troxler. You should have seen the crude first Troxler equipment. It is much improved now, but the general method is quite touchy.

Anyhow, as I then worked on many a job, it became apparent that if the nuke gage was off by anything, it was low on density. That is the reason why good calibration for your soil is necessary. In this case, you may find that to be one of the factors that affected you. Was the equipment calibrated for on-site soil, not some lab bucket of concrete.

Lab testing (Proctors), can be discussed at length with your problem, but you need standards that are generally accepted by the "industry", such as via ASTM to hang your arguments on.

Finally, of course, was the completed job performance deficient in any way? In other words did they really need 95 percent compaction? Of course some will argue these details, but a lot of work has been done that works out fine for end result and the 95 percent was an unrealistic thing to ask for. I have accepted compaction on some parking lots at 85 percent on clays and everything worked out fine. That 95 number also might be argued.

Good luck
 
i'll move my comments to this thread
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msucog (Civil/Environme) 30 Dec 08 20:47
while i'm not familiar with your specific project specifications, proctors are typically not performed for every single test. they are usually performed on soils determined to be "different" than previous proctors or if it is known/suspected that the soil has changed. from my experience as a geotechnical and construction materials testing engineer, i have never seen and would never fail a test without justification. the term "fail" is not simply restricted to a singular test end-result. there are several factors that can fail a test other than the final number. certain observations by the onsite geotechnical personnel can be justification to fail a test. the contractor's actions/inactions can fail a test.

i'm a little curious as to what magnitude monetary damage you incurred. if the tests failed, then i would expect that grading activites halted until that area/lift was remediated or corrected. was the soil too wet to achieve compaction? can you provide a few more details of the circumstances?
 
Hey cap

No expert here,... just opinion.


How critical is the procedure?
This is not an easy one to answer, especially if you do not know the procedure. (what part was poo poo'ed)
The gauge should be documented as stable. (you need to do some Troxler googling) The procedure should be done as stated in the owners test procedure, and as outlined in the gauges operators' manual.


"The inspector did not perform proctors on half of the tests taken when the owner's specifications outline the specific procedure to follow...?"

I am guessing the spec.s required sampling and Lab testing in order to obtain Moisture Density Curves/Proctors from Pit and or Cut areas used for embankment.

If tests were failing routinely, someone (your folks) should have verified which proctor the tests in question were based on.

There "should" be supporting documentation representing at least some of the alleged improper tests. If you can acquire it.

If you are saying "after the fact" that you were dealt with unfairly and cannot prove it, well you may be out of luck.

Did anyone witness testing? Specific comments?
 
Thank you all for the replies. I'll address specifics by name below:

msucog: I have read some of the other threads you have been involved with. Let me preface by saying that I was formerly employed with this particular owner. Compaction inspection was a large part of my job description. So I have a good foundation and understanding on this spec., but I'm looking for some other points-of-view. I agree with you that one should not fail a test without proper justification.. This is a spec. that calls for one-point standard proctors to be used with a "family of curves" (26 to be exact, like the alphabet! coincidence..)(strike sarcasm). Also, there is NO LAB WORK required by this spec. There is supposed to be a one-point to verify each nuclear test. The problem is, the insp. did not perform these for every test. The spec. calls out specific parameters for testing. For instance, embankment is to be tested at 8" probe depth. Some were run at 4" some at 6". Also, the spec. is written such that the contractor is to complete his compaction operation before testing, i.e. min. 8 roller passes. This tech was testing at 4 and 6 roller passes. I could go on and on. His documentation was littered with these type of mistakes. At "point break" of the situation we hired an independent third party lab to verify the results. The owner also brought another more experienced technician to the site (I'm sure out of fear of embarassment). Both of whom verifed that the tests were performed in error. This is all documented very well. We had also requested to perform proof rolling to verify stability. The owner's rep. said that this was not a viable verification. We did perform our own proof rolling with a loaded tri-axle dump. There were no signs of yielding, pumping, rutting, tearing...... IT WAS A SOLID FILL! We were directed to change borrow sites 2 times because the material was "too wet"(according to the troxler) and would never pass compaction. Again, these assumptions were made on halfast tests. When we brought the third party in, we had a full geotech workup done on samples from all three borrow sites, showing that all of the sites were suitable for emb. use. It was some of the best embankment money can buy. As far as magnitude of damage, 110k on a 3 mil project.

Drumchaser: Thank the lord we did document the heck out of this. We were able to secure the field test reports from the owner. Like I stated above, these reports were littered with critical mistakes. Yes, we did verify that the tests run were completely BOGUS! Also, the procedure from the owner for its techs is to standard count every week, or at location changes(which should be every day). This particular tech used the same standards for almost 3 weeks! I'm hoping for an open-and-shut case. We are going to DRB sometime next month.

oldestguy: Do you happen to know the numbers of the astm or aashto specs you would recommend?

Thank you all for your comments. I am looking forward to your responses. This is my second day with this site and I love it!
 
Hi Captain:

I gave away the ASTM specs I had, but I am sure that there is an ASTM index for the various test procedures. For AASHTO the same. Perhaps another discussor can help. I do recall having to bring up these requirements on jobs I have been involved with in the past and the calibration requirement did the job.

I did a Google search now and came up with three numbers for ASTM "Nuclear density". D-5195-08, D-6938-08a and D-7013-04. I think the last one is the one you want. These can be ordered on line. I'd get all three to be sure.

Another source if good information is the US Bureau of Reclamation. In one of their manuals they have a procedure for an even larger in-place density test for soil and rock mixtures.

Hey, I'd love to be in court on this one.
 
cap

Sounds like your owner is a local municipality, city, or county type. Surely this is not a S.T.A. (DOT).

Anyway, it sounds as though you have the foundation for recovering some of your costs. The unknowns are who you are dealing with (with regards to solvency), and the other particulars involved. It appears your owner has a process or criteria to follow regarding monetary claims. I hope so. Lawsuits (as you well know) usually only benefit the fellows with the jurisprudence sheepskins, and are slow to materialize.
Depending on what some of the particulars are: the owner quite possibly will settle beforehand vs. the obvious perception of gross malfeasance. So be sure and input all the incurred costs (with staggering detail and accurateness) into your summary of claim. I would be on this operation now.
Be sure to include major schedule disruptions and how it impacted the critical path. Weather/seasonal type work may have been lost in this process etc.

Your labor, materials, and equipment should be recoverable, as well as a set % of profit, overhead, and bond.

I concur with oldestguys reference to D 6938-08a,....also D 653-08a may be a good one to download (though it is large and is only terms “Standard Terminology Relating to Soils, Rock, and Contained Fluids”) it has been of assistance in the past.

Although our Test Procedures/Laboratory Testing Facility Criteria are based on and meet or exceed ASTM guidelines, they are easier (more user friendly) to follow. The ASTM’s tend to exacerbate some folks and are time intensive. This is not to say they are not the gold standard to which things are measured by.

Also, I do not see how your owner can specify Density Controlled Embankment and not require Atterbeg Limits and Moisture Density - Relations of the Soils in use.

would be most interested in your outcome

 
Thank you again for your input!

Drumchaser: Ha ha ha.. Your "surely not" is a sure thing. It just happens to be a State DOT. Yes, there is a provision in the contract for a Dispute Resolution process. Which makes this a bit easier. It is a four step process that I am fairly familiar with. You have given some great info. What I have been looking for is some particulars that would give our claim statement an extra ooomph!.
oldestguy: I am going to get after those spec no's really quick-like. I hope it never goes to court. The Claims court is actually managed by the owner.....

Have to get running to family events..! Hope you had a great new year. I'll have more to follow!!
 
Captain:

I used to be the head soils engineer (1958-63) for a state DOT and there were some problems like you describe, but we usually were fairly easy to work with. These days with private firms doing the testing and money being more tight, I suspect there will be problems resolving things. If state employees were there, then their training program might be questioned.

In this case also see about getting the AASHTO specs for nuke testing, since that may be more useful than ASTM. Hopefully the job secs made reference to them in some respects. Many AASHTO specs are the same as ASTM, but not always. I suspect a Google search will bring them up.
 
Hi Captain:

These AASHTO folks make it difficult to see just what you will get when you order from their WEB site. It appears that T-310-06-UL is available on line and probably covers what applies to the job. Cost is $120 to non members and you have to sign up first to be an "E-affiliate".

It would be good if one of the guys here, an AASHTO member, will clarify if this is the right standard.

I gave up membership some time ago.
 
Yeah, BigH, I apologize. It was my first time on this site, and I was grossly eager to get some comments. I apologize. I'll send a reply on that thread to point to this thread.

oldestguy: Unfortunately this particular DOT still engages in their own NMD testing, and with a spec. that is utterly out-of-date it makes it a little more difficult to "fight city hall." You have given some great information in this thread. Going back to one of your previous, do you think a "expert" on board would be beneficial? I was thinking that having an expert comment letter in the summary of claim submittal would be sufficient at this step. We planned on hiring an expert if it went to litigation.

Thanks again. More to come!
 
You probably can perceive that I have been an expert in court many a time. It is not all black and white and good attorneys sure try to make you look unqualified, etc. The general atmosphere of the case can be handled wrong and good arguments can go unheeded by juries. It's more than just talking about engineering. The expert has to be so well received and calm that he can't be rattled. A lot can be said about how to do the job as an expert.


I've had the misfortune to be sued once (claim was 8 mil.)(not due to my fault) and it was discussed as to whether I could be my own expert, but for good politics or some other reason an expert of about the same experience came on board. The suit was settled out of court. We were ready to go all the way however.

However, some experts are "hired guns" and that looks bad. In your case you are biased and that is not good. The psychology of how to best present or win arguments can be discussed with attorneys, but a true "expert" should come on board having no particular gain to make. It may be required to bring someone from a long way away, since some local engineers do not want to be on the black list with that DOT. It should be known that he has been paid up front or his fee is known to all (probably in a deposition). I've had attorneys quiz me in cross examination to try to show some bias and it pays to have it known you are paid regardless of the outcome.

So, the reason for an outside expert is more for how the case is to be won. Not always does good engineering know-how impress a jury. Not all engineers make good presentations in court. Too often it is necessary to make it very very simple. Not all attorneys understand the need for certain engineering requirements and so simplifying a complicated subject can be difficult.

With crummy specs to work with it seems that a logical presentation would include arguments as to what the standards are these days for this kind of work elsewhere in other DOTs. Not using AASHTO or ASTM standards would seem to be one argument that you have.

If you can, I'd have every DOT employee doing testing quizzed in depositions to see how they are trained and supervised, standards they follow, written records, etc. Showing the arbitrators how crummy the job is controlled probably can be done from what you say. What are the qualifications of the DOT spec writers?

It sounds like you have a good case. Hopefully no court time, but be prepared.
 
oldestguy: I wish I could sit and pick your brain person to person for hours.... You have a wealth of knowledge, and vast experience. Thank you very much. I agree with much of what you are saying. But, I do believe Lawyers do know how to dumb down a complicated subject. This provides a climate of "everyone can do this job." And in that case, Juries feel like a panel of engineers. Regardless, I digress. I don't know if these are necessarily crummy specs. I did operate under them for sometime. I worked for this DOT before moving to the private sector. The problem with it is, the DOT does not put as much energy and resources into finding qualified and motivated people to fill these positions. Most of the time it's politics and money that provides motivation. At any rate, I am working my plan along this line. Hammer on inadequate training and lack of regard for procedure/specification. I hope we do not get as far as court. We have 2 more steps before litigation. I do believe it will settle much before that. It may go along the lines of what Drumchaser was saying, they will be trying to aviod the appearance of gross malfeasance.

Thanks and more to follow!
 
Captain:

Sounds like you have it under control.

Here is an example of inexperience by some DOT staff. In the design stage for a relocation job they wanted to have the cut sites sampled and lab Proctors done well ahead of construction, by a private lab. The assumption then would be that these Proctors would then be used by inspectors on the job in controlling compaction so that no lab testing would be needed during construction.

Not sure if that ever came about, but I was interviewed as one of the prospective labs to do this. I didn't get the job probably because I expressed it as an impractical idea in the interview. The interviewing (supervising) engineers obviously were not experienced out on the job, but they had seniority.

Keep us posted
 
cap

Assuming your allegations have merit and your supporting documentation is unchallenged, additional compensation should be forthcoming.


oldestguy

This all kind of goes back to some other threads:
Common sense sometimes gets lost in the theory of soils testing. There are many test procedures: ASTM, AASHTO, and others that were modeled specifically in tune with these.
There is no substitute for experience in the field of play. An individual can know all there is to know about xyz procedure, but without using these methods in conjunction with common sense and previous experience, it can be a lost cause.

And punitive to industry.

According to others (in this forum) some org.s run verification for every density test performed. While I applaud this and would be overjoyed to be able to operate this way, it is not practical for several reasons.
It is has been my experience that the last decade or so the rest of the "old guard" has moved on to retirement, or other things.
I benefited from working with several of these folks when I came onboard. This arena used to be chock full of knowledge, experience, honesty, and fortitude. Those days appear (for the most part) gone.
Most folks are inherently lazy or in such a hurry to produce results (due to financial, upper mgmt., and other factors) they forget to do it right the first time. And when they have to correct the problem, the finger pointing comes out.
Overall, the pool of experience from all sides of industry has apparently eroded to the point of ridiculousness.

 
Drumchaser:

How right you are. Sounds like my kind of engineer.

In the rush to be competitive, short cuts and "new methods" are showing up. I like computers, but distrust complicated software. Spreadsheets have helped me tremendously and of course word processors did away with secretaries. A few of them disliked my changes of typed reports!!!

I recall in the old days of the wash-boring procedures when 30 feet in a day was a good one and now with hollow stem augers doing that much in maybe an hour or two.

I also remember when a young hydrogeologist (a term that was not known way back ) predicted a sewage lagoon would not work, but would soak away based on these quick drilling method, but it did work. Then, taking a back-hoe test pit later on and finding those thin clay layers that held the water perfectly to explain why the site worked. A sample taken every 5 feet might be OK many times but not that time.

Back to compaction testing, I always required techs to probe the ground with a 1/2" rod fitted with a T handle. If that showed good resistance, then failing percentage compaction results were immediately put into question. Numerous times that rod probe pointed out where other checking was needed It sounds crude, but hundreds of jobs have been done with that device on the job and minimal haggling is required. I point out that with uniform sands this does not work. The dynamic cone penetrometer may be better for the inexperienced, but more time consuming. Fun stuff.

 
Unless I missed something in the foregoing thread, they only did "one point" Proctors and developed a "family" of data? A "one point" moisture-density relationship is no better than the density test itself and is not an appropriate comparison. The use of a "one point" Proctor is to determine if you are on the right laboratory Proctor curve...nothing more, nothing less. If the one point value doesn't sit on or near any of the laboratory curves, then you need to run another moisture-density relationship curve in the lab using that material.

I have evaluated numerous claims such as this and as someone stated, poorly specified testing and poor control over the testing/evaluation process cause monumental problems. Usually, with careful review of data and some additional field testing to validate the data, an appropriate answer can be found.
 
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