UG-29 - Stiffening ring - lateral buckling

[monk1999]

Hi,

In BPVC Section VIII, Div-1, Subsection UG 29 on stiffening ring, there is a paragraph that says "CAUTION: Stiffening rings may be subject to lateral buckling. This should be considered in addition to the requirements for Is and I's [see U-2(g)]". How is lateral buckling generally analyzed for stiffening ring or not analyzed based on certain engineering judgment?


Thanks,
Monk

 

[r6155]

See Code Case 2286.

Regards
r6155

 

[jtseng123]

Engineering judgment: for plate type ring, width not to exceed 10 times of ring thickness, not to exceed 8 times is preferred. This rule applied and not heard of any problem so far.

 

[r6155]

@ jtseng123
Please, can you tell us the literature?

Regards
r6155

 

[monk1999]

Thanks for all the reply!

FYI, after some more digging, check out page 11 of this literature that I found online that provides a width to depth ratio of the ring section based on the Young's modulus and yield of material.

https://pveng.com/wp-content/uploads/2016/06/External-Pressure-Calculations.pdf

The equation used in the above literature is based on theory of compact vs non compact sections. Here is a link for brief explanation:

http://www.wikiengineer.com/Structural/SteelBeamCompactSections

ASME BPVC 2286 Figure 1.4.4. has the same information as guide for width to depth ratio. That case number has a lot of information and I am still slowly trying to digest everything.

Regards,
Monk

 

[jtseng123]

@r6155, that is quick and dirty rule of thumb for decades. Handbooks or company spec may have that.

 

[r6155]

More literature
1) PD 5500
2) AD 2000
3) BS EN 13445

Regards
r6155