Wind Loads on Thin Tubular Sections

[45North]

I am a civil/structural but am posting this on the ASME forum hoping it is something covered in the pressure vessel code.

I am looking for a reference on calculating local defromation of a thin tube due to wind loads. This is for determining the flatening or ovaling stresses. I have a reference for Krupka (in Czechoslovakian of course)and several formula but the results make little sense. I suspect it is an issue with conversion of units.

Smax = (1.566*q*R^2)/t^2) + (0.212*q*R)/t

Does anybody have a reference that give the correct units?

Does anyone have a refernce they can suggest?

I may be able to get my hands on a pressure vessel code in a few days if need be.

Thanks

 

[JohnBreen]

The ASME B&PV Code is NOT a design handbook. The Code provides rules and some equations for calculating minimum thicknesses and some equations for calculating various stresses. The Codes provide equations and tables for determining the allowable maximum stresses. The Code allows the user to supplement the design rules by using alternate, more rigorous methodologies (the approach must be documented). You will not find equations for calculating the deformation of thin wall tubes (etcetera) due to wind loadings in the B&PV Code. You will not find explicit equations for calculating the deformation of thin wall tubes (etcetera) due to wind loadings in the ASME Code for Pressure Piping. The B31 Codes do provide equations for combining various stresses using the Tresca failure criteria. However you can use established methodologies (e.g., Roark, et. al.) to calculate deflections and stresses due to any loading and follow the rules of the ASME Codes to calculate the allowable stresses for comparison.

Regards, John

 

[45North]

Thanks for the reply John.

I recently changed employers and have a copy of Roarks and a couple of other reference books are on order.

I will run an FEA but I always like to have something else to provide a GIGO check. This is one of those things that are difficult to do a reality check on.

 

[doct9960]

45North,

See if the article below can give you some insights. The author also has some references at the end.

http://www.kuleuven.ac.be/bwm/papers/doomip04a.pdf