Wind Engineering

[beam123]

I am trying to calculate the wind forces for the main wind resisting members for a steel building h > 60-feet and I am confused if the internal wind pressure has to be added. I think it does, but others where I work say because it acts in all directions it cancels for the MWRS. Which is correct?

 

[JedClampett]

It cancels except on the roof, so if you're looking at a combination at the column or vertical bracing design, it might make a difference. It's unlikely, but I bet someone can give an example where it was a critical issue.

 

[Once20036]

If you have an expansion joint it won't necessarily cancel.

 

[UcfSE]

Always account for the internal pressure properly. When it cancels, the math will show it. When it does not, the math will show that also (as long as you're in thinking mode). Internal pressures do not cancel when the walls are not parallel.