×
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

Cracking on industrial slab

Cracking on industrial slab

Cracking on industrial slab

(OP)
Hi all. I have attached a photograph of some slab-on-grade cracks in a grid pattern. I have some ideas on cause but I wanted to poll the group. The slab is in an industrial shop and the photo was in the aisle for heavy axle loads. The documents are not very clear but seem to indicate a 5" slab with 10M? rebar at 16 inches on center, over vapor barrier, over 6" crushed granular base "Type 33 compacted to 100% Standard Proctor", over clay subgrade. The slab was poured in winter (-13F) with reportedly little or no heating of the ground prior or during the pour. Cores show 4" to 7" of concrete at 3000 to 4000 psi strength. Water table about 3ft below slab.

TIA

RE: Cracking on industrial slab

What kind of heavy axle loads... 5" slab is too thin for this... Cracking is extensive, but, does not indicate heavy fatigue type of loading. Crack edges are sharp and would expect them to be more rounded. Maybe cut out and replace with quality 8" slab for heavy channelised loads.

Dik

RE: Cracking on industrial slab

Looks like it cracked at every bar. I'm going to go with plastic settlement cracks worsened by insufficient concrete thickness for the axle loads. Can you pour a thickened topping onto it?

Professional Engineer (ME, NH, MA) Structural Engineer (IL)
American Concrete Industries
https://www.facebook.com/AmericanConcrete/

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