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


Notched Beam Solution with Nailed-on Sister

Notched Beam Solution with Nailed-on Sister

Notched Beam Solution with Nailed-on Sister

Hello all,

Here's the story:

The plumber thought it would be a good idea to notch a 5"X5" square directly at the bottom of a 1.75"X14" LVL 2.0E joist, about 1/3 of the distance in on a 20' +/- total span. The contractor on site has asked me to run a calculation evaluating a 3.5X9.25 PSL 2.0E sister spanning 6'-0" directly centered over this notch, with 2 rows of 16d nailing @ 4" O.C fastening the PSL to the LVL. My question is if anyone has any reference materials they can point me towards to run the analysis for this condition. I would need to evaluate the bending in the PSL as forces are passed through the nails. Anyone have any suggestions?

Thanks a lot folks,

RE: Notched Beam Solution with Nailed-on Sister

Some recommendations:

1) Remember that, if you don't jack the beam to relieve stress, you'll need to account for those stresses at the notch that will be baked into the cake.

2) With only about 3' of reinforcement either side of the notch, I wouldn't bother trying to enforce flexural compatibility between the LVL and PSL. I'd just treat the PSL as a tension strap resisting a conservatively estimated tension.

3) I'd use angled screws rather nails to improve stiffness.

4) I'd use a member on either side just to improve symmetry.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

RE: Notched Beam Solution with Nailed-on Sister

There are several things you can do for this. Sistering is bulky, but if the beam is hidden is doesn't matter.

Some other methods to consider:
Use a repair flitch plate in the same shape as the notch, made of 1/8" to 1/4" thick steel plate on both sides. Thru-bolt the plates.

Use threaded rod on the bottom of the beam to take the tension.

One major goal of any of these repair methods is to prevent migration of cracks that eminate from the corners of the notch.

As KootK noted, jack the beam up to take out deflection before doing any repair.

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!


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