Imperfection in nonlinear buckling

Kacper_S

Hello

I have few questions

1.  I want to do some nonlinear buckling analysis using imperfection. At start I made linear buckling and imported h3d file to the second model using ASSIGN card and IMPERF load collector, but it didnt work I guess because I don't see any buckling in results, only axial compression. HM and h3d files below. What should I do to make it work?
2.  How to get safety factor in such analysis or critical load?
3.  How to make xy plot with force? Sth like this in appendix

Thank you for your help

13296_2019_268_Fig7_HTML.png

60.66.008.00.00 rura 1N.h3d

60.66.008.00.00 rura 1N.hm

60.66.008.00.00 rura nieliniowa.h3d

60.66.008.00.00 rura nieliniowa.hm

Jason_Craanen

Hello,

I would take a look at the following articles to start

https://community.altair.com/community/en/flat-panel-post-buckling-analysis-with-implicit-method-using-optistruct?id=kb_article&sysparm_article=KB0037316

https://community.altair.com/community/en/buckling-methods-in-optistruct?id=kb_article&sysparm_article=KB0117377

https://help.altair.com/hwsolvers/os/topics/solvers/os/analysis_technique_imperfection_r.htm?zoom_highlight=imperfection