Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Suggestions for Test Methods...

Suggestions for Test Methods...

Suggestions for Test Methods...

Having secured our Accreditation for Concrete testing, I am now starting the process for SOILS. We do not require accreditation in a great number of Standards, just basic Identification and Moisture-Density should be sufficient.
I will pursue both ASTM and AASHTO methods for proctors as both are cited in many job Contracts.
Otherwise, I think we will stick with ASTM for Sieves, Hydrometers and Limits.
My question ( besides general advice) is what is the best (easiest) method for Specific Gravity of Soils? What I know of the ASTM method seems unnecessarily complex, and tedious. Is there a better method? What do you all use?

RE: Suggestions for Test Methods...

I'm curious. Will you folks also be doing field sampling and testing? If not and only doing lab testing, I'd not expect much work coming in.

RE: Suggestions for Test Methods...

Mike...I'd rather guess the specific gravity based on the soil type than run the tests!lol

Unfortunately, for accreditation, you'll need the capability to run at least the water pycnometer version for soils. If you're in an area where the soils might contain a lot of organics or have constituents that would be dissolved or go into solution during the test (calcareous silts for example), you'll probably need the gas pycnometer method as well.

Other than that, the procedure for concrete fine aggregate is simpler and probably as accurate as any. I've never considered the specific gravity test to be as accurate as the significant figures would imply!

RE: Suggestions for Test Methods...

Ron, my sentiments exactly. Just because we can calculate to 3 or 4 or 50 digits doesn't mean that "information" is of any value. The very next scoop of soil will be different. When I first learned Proctors, the standards merely required that the blows from the rammer be equally distributed across the surface of the soil. Now we have a prescribed pattern that MUST be followed. Too many people "trying to make a difference".....
Hey, you kids----get off my lawn"
Yes I am the curmudgeon.
I have decided, to use the AASHTO T100 standard for Specific Gravity.

Yes--OldestGuy--we will also be doing field testing, but so far, none of our clients require accreditation for density testing.

RE: Suggestions for Test Methods...

Another question.....
I have been running D422 ( Gradation with hydrometer) for years. Sometimes w/o the hydro, which I understand means that the test was not run according to the Standard, as the hydrometer portion was not optional, even though it was often treated that way.
I see they have broken out the sieves only portion of the test and issued it as ASTM D 6913.
I also see a new Gradation with hydrometer issued as ASTM D7928
Further....AASHTO still certifies under the old ASTM D422 Standard.

Now the questions...
Do any of you have experience with the newer standards ( D6913 or D7928) and care to share your opinion? My volume of the ASTM soils doesn't include those numbers, so I will have to purchase them separately, if I need them, so I am asking for opinions as to whether I should just go ahead and get them. My guess is that eventually the AASHTO inspectors will require them and not accept D422.
Are there any major differences with the new specs? Any surprises?


RE: Suggestions for Test Methods...

I read ASTM is working on a standard that combines sieve and hydrometer, see here.

RE: Suggestions for Test Methods...

D422 is withdrawn.
D2487 is needed to actually classify soils.
Get the specific gravity certification!
How about extracting tubes?

There is also the R18 certification? Google it? I think I got that right?


ípapß gordo ainÆt no madre flaca!

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close