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!

*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.

Jobs

Shear thru thickness of plywood in plywood-timber I beam not computing.

Shear thru thickness of plywood in plywood-timber I beam not computing.

Shear thru thickness of plywood in plywood-timber I beam not computing.

(OP)
Threaded deleted. We found what we needed. Thank you!

RE: Shear thru thickness of plywood in plywood-timber I beam not computing.

(OP)
OK, I guess we are back on this search so hopefully my previous delete is ignored.

We are trying to calculate and predict design and ultimate load predictions for wood Ibeam construction with timber flanges and a single plywood web. We did some destructive testing of some in-house built I beams and seems our numbers were quite conservative and we are trying to pin a couple things down.

Shear through thickness seems to be our biggest point of complication. Our predictions indicated a failure through the thickness but our tests were unable to induce this failure mode as roll shear took a front seat. We also held a LOT more load than what was predicted, indicating we may have some calculations wrong.

Per the PDS manuals for shear thru thickness and thickness for shear, in both the main manual and the supplement regarding plywood-timber beams, these resources indicate a certain value for shear and thickness for shear. However, in another supplement for "all plywood beams", they indicate much different values for shear and thickness for shear, seeming to boost the thickness for shear by over 60%! Now if we were to apply those values, we might be much closer. However, I am still confused a bit as to why they are applying such an increase to shear capacity to an all plywood beam, but not a plywood/timber beam.

They do include a stapling schedule for the plywood glued beams. We are using heavy nails in our Ibeams but documents seem to indicate to completely ignore their existence in the calculations even though there is certainly interaction there in helping to carry shear to the inner plies.

Is anyone experienced enough in these areas to help point us in the right direction? We are mostly doing this as a research and learning experience right now, being fairly new to wood properties and behaviors.

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


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