×
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

Chord Members

Chord Members

Chord Members

(OP)
Whenever I design a building, I run my numbers, check the walls for wind and seismic, etc. During the diaphragm check, I calculate the global moment on the whole diaphragm and add chord members (reinforcing, angles, overlapping wood plates, etc.) just like the textbooks say.
My question is; Has anyone ever seen a failure due to lack of these chord members? It just seems counter-intuitive that a couple of #5 bars (or angles) at the bearing level in a building are going to do very much. I know the numbers require them and I'll continue to provide them, but they seem pretty cheesy.

RE: Chord Members

I have never seen a failure of that kind even when chord reinforcement is omitted.  I suspect the diaphragm usually has enough capacity to carry the chord forces without additional reinforcement.

BA

RE: Chord Members

The chord forces are added incrementally to the wall/chord as well.  So, especially in masonry, there's plenty of space for those forces to get distributed to other reinforcing throughout the wall.  

This got me thinking about diaphragm failures and how I'd never seen one in person or photos.  So I head over to google and you can imagine my surprise upon searching for "diaphragm failures".

 

RE: Chord Members

(OP)
It's like doing a search on Red Head anchors.

RE: Chord Members

Azcats:
I didn't bother to look or Google "diaphragm failures," but I can just imagine.  You've just got to bring sex and pregnancies into ever engineering discussion, don't you?   smile
I'll bet those weren't the topics JedC had in mind with his OP.
 

RE: Chord Members

(OP)
Those are always on my mind, but I manage to fit some engineering in occasionally.

RE: Chord Members

I want to say that there have been some failures in seismic events where the pieces weren't properly tied together, although I can't remember where I read that..  although that may be a load path continuity issue in general more than a chord reinforcement issue in particular.

RE: Chord Members

ooops..  to clarify: in precast structures.

RE: Chord Members

The only issues I have seen were at re-entrant corners (diaphragm tearing). Not really related to the chord tie.

Jed- I have made that mistake as well. I was trying to find the required embedment length- not quite what I had in mind.
 

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