×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

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

Jobs

Determination of Soil Settlement

Determination of Soil Settlement

Determination of Soil Settlement

(OP)
I have just removed a section of very impermable clay that was 1.5m deep by 150 square meters. This was backfilled with topsoil and gravel to improve the permeability and tests were carried out to determine how long it would take a specific volume of water to soak away. This test was regulated under certain conditions and they all passed. My only issue now is that I am trying to determine how much if any settlement will occur within the soil mass. It will not be loaded and I assume there must be some kind of formulae that can be used to determine this settlement.

RE: Determination of Soil Settlement

If this is for a septic field, why need to know settlement - sure it will settle with time especially with topsoil being used.  Just "top it up" as needed; may cause homeowner to redo his lawn one or two times.  The self-settlement will really depend on how well you compacted your topsoil/gravel fill.  If loose, like I presume it is, it will settle more than if compacted; but then if compacted, you probably wouldn't get the seepage.  Don't forget that as it does settle, the seepage flow will become slower.

RE: Determination of Soil Settlement

(OP)
Thanks for your reply BigH. You are correct in stating that the soil will settle over time and that seepage will become slower. However my problem is that I need to prove how much settlement will take place and how much the seepage will slow down by. Is there any calculations that can be done to determine this.


Regards
Nana1971

RE: Determination of Soil Settlement

Hmmm,

Not really.  Too many factors to consider.  If this is a critical consideration, then you will need to increase the size of your drain field to allow for permeability reduction over time.  Remember that biological clogging of the pore space may be a bigger (and more immediate) factor than soil settlement -



Please see FAQ731-376 for great suggestions on how to make the best use of Eng-Tips Fora.

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!


Resources