Wind load on debris netting

[anchorengineer]

I need to convert a tested permeability of a debris netting to a % solid. I have the permeability in cfm/sf. I know i need to use a formula in ASCE 7 for wind pressure =0.00256*V^2*some factors. Can someone help?
Thanks!

Clarke Engineering Services, PC
Construction Consulting & Anchor Testing

http://www.anchorengineer.com

 

[Sparweb]

Try the factors that apply to lattic structures or trusses. Not totally dissimilar. The building code may work. A book by Sighard Hoerner called "Fluid Dynamic Drag" has general and test data on "perforated disks" and "pervious sheets and parachutes", both of which look applicable to your net.

You have test results? It would be interesting to know how the calculation compares to the reality. Is the netting flexible? If so does it oscillate in the air flow? Obviously I don't know how big it is, but since you are asking the question I assume it's a sizeable component. I bring it up because a flapping net will apply dyanamic loads, not just static ones.



Steven Fahey, CET

 

[chicopee]

Have you contacted you debris net distributor for such info.

 

[dhengr]

Remember that collected debris means 50 - 60% solid wind surface, take your pick. It is a tension net problem, as in cable structures, btwn. the support poles; and then the exact % solid surface, anyone’s guess, dictates the loads on the cantilevered support poles.