×
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

box tube strength

box tube strength

box tube strength

(OP)
Looking for the amount of weight for a 2x2x1/4 box tube 20' long vertical with a 3'x2x2x1/4 box extension on top and base is 12" 2x2x1/4 box with 6x6 gusset on 2 sides of top extension and base, noticed alot of flex in the tubing because of the length but was wandering how much would it hold before bending or breaking ??

RE: box tube strength

I would look at buckling of the column as the first failure mode. Treat it as a complete column first and use Euler's formulae to give you the buckling load.

RE: box tube strength

Tube 2X2X1/4 is very slender member for the 20 foot height. I would never use suck a slender member. That may explain why it is so flexible.

I would be concerned with buckling more than bending as corus explained above. If you must use the same tube size, consider reducing its unsupported length/height.

Good luck.

RE: box tube strength

I agree w/ Corus and Lutfi - 2x2 and 20' in height? Even it would carry the load w/o failure, the servicibility of it will be a problem.  The deflection would be huge and the vibration (bouncing) will be a problem as well.

Anyway, if you are to use it, here;s a list of limit states whatI think you should check:
(1) Local Buckling of Plates in the tube, i.e. b/t ratio
(2) Overall Column Buckling

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! Already a Member? Login


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