Membrane Cover Uplift

[Beamman]

Hi,

I have a membrane cover at the top of a 60' high storage tank with 2' of freeboard. The cover droops down and touches the liquid.

Is there a way to calculate what the wind uplift would be on this cover.

Thanks for any suggestions.

Mark

 

[JStephen]

API650 and ASCE 7 include design loadings for uplift on roofs, but they are not necessarily applicable to a floppy dynamic roof.

One consideration is that the uplift can't significantly exceed the tearing strength of the fabric- I've seen posts elsewhere where this was taken advantage of in awning design and the like.