uplift wind load

[rcmac]

I am a mechanical engineer and I have designed a 12' round and 75' tall piece of machinary for outdoor use. I hired an outside engineer to calculate wind load, moment arm and uplift numbers for forces acting on concrete foundation. I can verify wind load and moment arm, however I have not been able to verify uplift. He calculated this through a self made software program. I want to know if anyone can lead me to a good uplift equation?

 

[UcfSE]

Uplift equations are usually just based on static force and moment equilibrium. Are you familiar with the load combinations used? To find net uplift we usually check the load combination 0.6*Dead +/- 1.0*Wind for service loads, or 0.9*Dead +/- 1.6*Wind for ultimate loads. Do you have a specific question or is that what you're looking for? Try drawing a FBD also.

Since you hired this engineer and he/she works for you, you may request his calculations and an explanation assuming they will be worked in the fee if they are not already in it.

 

[JStephen]

rcmac, usually I think of uplift as uplift due to overturning, not direct vertical uplift- you might check which he was actually doing? I wouldn't think this would take much in the way of software.

 

[jike]

First, you need to ask which code he used to calculate these loads. The calculations may have their basis in ASCE 7, but you need to know what version.