How Can I Account for Wind Loading in Calculating Buckling Load on a Beam?

[Banana-Man]

Hi all,
I have recently been asked to calculate the Buckling load on a beam (channel) carrying pipes, (Eulers critical load) this was no problem. Then i was asked to allow for wind loading.. I can not for the life of me figure out how to do this?

Any tips for me?

Thanks in advance

 

[jrmichler]

Is your undergrad degree in engineering or physics? If so, wind loading is the velocity pressure (Bernoulli's equation) at the design wind speed for your area times the coefficient of drag times the projected area of whatever the wind is blowing on. Wind loading is a distributed load, and normally in the horizontal direction.

 

[tech99]

I think the wind will apply a bending load to the beam at the same time as the compressive load. Steps might be,
1) Find the design wind speed. Depending on the level of security required, it might be the once in 50 year 3 second gust. You should be able to find a code enabling you to find this for your location. Typical value is 100mph.
2) Then calculate the wind pressure and the projected area and shape/drag coefficient of the structure, (typical 40 psf in Imperial) and so find the force.
3) Find the stress in the members by analysis.
4) Allow a safety factor by finding the permissible stress in each member from a code.
5) Usually, compressive loads are the worst case.