[Towertalk] Wind info for VE7 - where can I find it?

[kr7x@attbi.com]

Jim:

Be aware that this is the design wind pressure at 0' or 
0 meter elevation... The US codes specify design wind 
velocity at 30' up. The US codes do not start with 
design pressure.

Hank Lonberg, P.E.,S.E.
KR7X


> On Thu, 15 Aug 2002 Hank Lonberg wrote:
> 
> >The BC code and National Building Code of Canada do not
> >use wind velocity. They use a design velocity pressure
> >in kPa based on recurrence frequencies of 1 in 10yrs, 1
> >in 30yrs, and 1 in 100yrs. The value you seek is the 1
> >in 30yr value.
> >
> >From Appendix C 1998 BCBC, the values for Vancouver,
> >including Richmond, Surrey and W. Vancouver are as
> >follows:
> >
> >1 in 10 : 0.36 kPa  = 7.72 psf
> >1 in 30 : 0.44 kPa  = 9.19 psf
> >
> >You could convert these to mph via p=0.00256*V^2.
> >Like all codes the design pressure is modified by
> >several factors to account for terrain, gusting and
> >height above the ground.
> 
> Amazing how the conversion yields almost exactly 55 and 60 mph!
> 
> 
> -- 
> Jimmy Weierich, K2LV,   ex KG2AU       <kg2au@stny.rr.com>
> Vestal, NY  USA           FN12xa