×
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

Expansion joint on Mat Foundation

Expansion joint on Mat Foundation

Expansion joint on Mat Foundation

(OP)
Hello There.

I have a mat foundaiton, 40m * 20m (LXB), with several extreme equipment load on top, settlement in each point is asked to be consist since those equipments are connectted by rigid large-size pipe. I am going to study it via finite element analysis. My question is as follows:

1. Whether I need set expansion joint for such large mat foundation,
2. How is such expansion joint modelled in FEA if needed?
3. Is there any impact to the foundation settlement if expansion joint is set?
4. Any other joint, e.g. control joint, shall be considered?

Thanks in advance.

RE: Expansion joint on Mat Foundation

You need to identify in your code any extant mandatory expansion joint (even if related to the particular way of design). Quite likely the walls would at 40 m long require such expansion joints in the standing building foundations' code in Spain. I however am still reluctant to excessive jointing in walls and mats, for integrity and monolithism can make for any advantages purportedly gained from dubious jointing from a waterproofing viewpoint, that uses to be the case when referring to cellars.

We have worked on far bigger mats for buildings without any joints at level -1, perhaps 4 times that long. No probs have resulted. These were thick structural mats, say on the order of .6 to 1.1 m thick.

A proper expansion joint structural model needs to show the expansion joint in the mat. Other than that is ordinary structural modelling, that may need to use (depending on the attempted approximation of the behaviour) software able to portrait the geotechnical aspects of the soil.

The impact of the expansion joint in settlements should be small, but there maybe some, since the lack of continuity causes some different working loads in the soil. However, for foundations, except from big rigidity of the foundation and/or joined superstructure, the main influence comes from magnitude and position of the loads.

I normally for thick mats with enough thickness and rebar would try to avoid control joints affecting the structural mat.

RE: Expansion joint on Mat Foundation

(OP)
Thanks ishvaaag.

I didn't find any mandatory spec for mat foundation that expansion joint shall be set, thus i am not going to apply any joint in this mat footing.

RE: Expansion joint on Mat Foundation

A 40m x 20m mat is not large. Cast it in one piece. Even if you have to have a construction joint, it should not be a movement joint.

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