×
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

How do i know how many buckling modes should i introduce as imperfections in Riks?

How do i know how many buckling modes should i introduce as imperfections in Riks?

How do i know how many buckling modes should i introduce as imperfections in Riks?

(OP)
Hello. I am modeling a simply supported beam and, as a first step, i had buckling procedure where i found eigenvalues and buckling modes. I have introduced the first mode as an imperfection, but i get that the Load Proportionality Factor is greater than the eigenvalue for the same load magnitude. Am i doing something wrong or i just need to introduce some more modes as imperfections? If so, how do i know how many modes do i need and which percentage of each mode do i need to include?

RE: How do i know how many buckling modes should i introduce as imperfections in Riks?

Don't compare the results of a fundamentally linear elastic analysis method with a complicated non-linear one. Perhaps compare your non-linear to test results. And concern yourself with the magnitude of the perturbations more so than the number of modes.

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