Smart questions
Smart answers
Smart people
Join Eng-Tips Forums

Member Login

Remember Me
Forgot Password?
Join Us!

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips now!
  • 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!

Join Eng-Tips
*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.
Jobs from Indeed

Link To This Forum!

Partner Button
Add Stickiness To Your Site By Linking To This Professionally Managed Technical Forum.
Just copy and paste the
code below into your site.

DougB (Geotechnical) (OP)
7 Nov 05 16:46
What do you consider a reasonable maximum organic content to specify for engineered fill placed under a building foundation?  Material in question is a silty clay bordering on a silt.  I am expecting 0 to 6 feet of fill under the footings (ie depth varies).  2 story wood frame construction for condominiums.  
eric1037 (Geotechnical)
7 Nov 05 17:30
We traditionally recommend NOT using soil with more than 4% organics for engineered fill.
DougB (Geotechnical) (OP)
7 Nov 05 17:34
Thanks.  Material in question came in at 3% and I was thinking a 2% limit was too strict but 5% seemed a bit too lax.  So that 4% limit works for me.  I'll consider your response standard of practice :).  Kidding.  But if anyone else has a comment I'd be interested.  
jdonville (Geotechnical)
8 Nov 05 9:52

We generally recommend 3% max by dry weight. Obviously, no large organics (stumps, branches, roots, leaves, lumber or construction debris, etc.).


Jeffrey T. Donville, PE
TTL Associates, Inc.

Helpful Member!  geociv (Geotechnical)
8 Dec 05 22:13
DougB - why use a silty clay borderline silt as structural fill below a foundation?  Wouldn't a granular material be a better choice (for compaction and sturctural capacity).  Silt and silty clay are highly moisture sensitive and depending on the location of the job, the contractor could have serious compaction problems if the jobsite gets wet.  Of course, a good contractor could make the material work, but I've learned to plan for the worst case scenario (i.e., low bidder!j/k).
cbosy (Geotechnical)
15 Dec 05 17:23
I agree with the 3% under footings and maybe up to 6% under slabs that could tolerate a little settlement and cracking.

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!

Back To Forum

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