×
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

cmu corbel / ledge design

cmu corbel / ledge design

cmu corbel / ledge design

(OP)
Anyone know where to find info on designing a cmu ledge for supporting second floor wood i-joists? (2 story building)
I'm planning on using an 8" cmu wall, and then corbel-out two courses of 12" cmu to create a bearing ledge for the joists.
Not sure how to reinforce the 12" courses.
Thanks.

RE: cmu corbel / ledge design

Why a corbel? Can you not use joist hangers?

RE: cmu corbel / ledge design

(OP)
Originally the floor LL was 60 psf, but now the owner wants to use 100 psf. My original detail was to use an 8x4 ledger angle with bolts every 24", but the bump in live load required too many bolts. So I decided to find another option. Maybe I'll look at using hangers screwed directly to the block with Simpson Titens. Thanks Tony.

RE: cmu corbel / ledge design

You could use a concrete tie beam unless it is exposed CMU, and you can get much higher bolt values or use a CIP connection.

RE: cmu corbel / ledge design

(OP)
A concrete beam was definitely one of the other options, but I decided that getting the two trades involved wouldn't be efficient.

RE: cmu corbel / ledge design

There's a mention in ACI 530-13, section 5.5, which refers you later chapters:

5.5.1 Load-bearing corbels
Load bearing corbels shall be designed in accordance with Chapter 8, 9, or 10.

So, your on your own with engineering principles and basic masonry design for shear and bending due to eccentricity in the wall.

I'll add that 11.1.10 states that "Load-bearing corbels of AAC masonry shall no be permitted." (autoclaved aerated concrete)

RE: cmu corbel / ledge design

Why not add an angle iron below your ledger - bolted to the 8" CMU?

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