RE: Wind Loads

From: <Steve>
Date: Wed Jan 14 2004 - 22:19:00 EST

59m/s (212 kph) is a fairly savage average wind speed even at 10m. For reference 30lb/sq ft (about 108mph or 48 m/s ignoring downstream drag)used to be used for bridge design peak nominal wind load and 100lb/sq ft for blow out of square rigged sailing ship sails. Hate to think what your peak wind speed is. Hope you are installing some wind turbines.

Cheers

Steve

-----Original Message-----
From: Thomas Laupa [mailto:tlaupa@frii.com] Sent: Thursday, January 15, 2004 3:46 PM To: <a href="/group/PipingDesign/post?postID=8TrgSNqvXkY9fiuNSEEHcxP3ei6fdskHL67sc02HwYdDVxc54X0mzlZyqLJ3m4qkJk5-lrV9GgfbHWrbxResc6iXFQ">PipingDesign@yahoogroups.com</a> Subject: [PipingDesign] Wind Loads

Sir:

we perform wind loading calculations periodically on structures, but not necessarily on pipe.

we follow the Uniform Building Code. as we interpret it, it makes no distinction regarding prevailing winds. therefore, we apply wind load in the most "critical" direction.

most of our structures, however, are walls and tanks. the "critical" direction is usually obvious.

hope this helps.

At 10:25 PM 1/14/2004 +0000, you wrote:
>I think it would be safer to try W and NE and possibly a more
>critical direction as well. Since 10% of the time the direction could
>be anything, I would take worse case direction. Sometimes one can
>easily tell what direction is more critical for wind by just looking
>at the model. If you cannot, you may try X and Z (assuming Y is
>vertical) directions and use worse wind case out of these.
>
>It is true that the probability of wind blowing at that speed for a
>more critical direction, other than W or NE could be lower, but if
>you cannot rule it out or calculate a lower wind speed corresponding
>to the lower probabilty for that direction, I would rather use the
>same wind speed for all directions and be conservative.
>
>Regards,
>Karim Rinawi
>
>--- In PipingDesign@yahoogroups.com, zope_tushar@f... wrote:
> >
> >
> >
> >
> >
> > Friends,
> >
> > In my current project, the average wind direction is west for 60%
>of the
> > year and the direction is N-E for 30% of the year.
> > Avg wind velocity at 10m elevation is 59 m/s. Max line size is 16"
>with
> > 100mm insulation.
> >
> > What is your opinion about the load case for wind?
> > I mean do I have to analyse two separate load cases or just West
>direction
> > case is sufficient.
> >
> > We are already analysing all lines for X and Z direction seismic
> > coefficient of 0.24g (Y being vertical direction)
> >
> > Best Regards.
> >
> > Tushar Zope
> > Extn: 162
> >
> >
> >
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Thomas G Laupa PE
Senior Engineer - Nalco Company
Office Address: 1601 Diehl Road, Naperville, IL, 60563 Courier Address: 1003 Remington, Fort Collins, CO, 80524 970-227-5127
800-493-5009 fax

---

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Your use of Yahoo! Groups is subject to:   <a href="http://docs.yahoo.com/info/terms/">http://docs.yahoo.com/info/terms/</a> Received on Wed Jan 14 22:19:00 2004