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!

*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

Raft slab on bored piers

Raft slab on bored piers

(OP)
I have a residential house project brief calling for a raft slab / slab-on-ground with perimeter edge beams only (no internal beams).
The internal area of the slab is proposed to be supported on bored piers only, extending some depth into the underlying clay foundation.

I am seeking advice on the recommended depth the piers should extend into the foundation material in order to provide resistance to seasonal moisture changes of the clay foundation material. This, I believe, should be at least the depth of expected seasonal/long-term moisture change (ie. height of suction) - eg. 1.8-2.7m (6'-9') minimum or possibly deeper. But a previous design I have viewed shows only 1.2m (4') embedment in to the ground and only approx. 0.6m (2') into a very stiff clay layer. I also believe this approach is similar to the one that should be taken when dealing with seasonal/long-term moisture changes associated with trees near foundations.

Any comments would be appreciated.

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


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