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Re: Dead Load or Live Load?

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I haven't heard about the building type but if it is wood framing, this
would considered a dead load based on duration of load with Cd = 1.

We consider mechanical units as dead load.   If they change out the units
10+ years to something heavier, the framing gets reanalyzed for the
increased loads.

What about roofing material weights?  dead load
The 2nd layer of roofing material?  These items are also stripped off after
10 years or so.

All of the above weights are used in the seismic calculations.
Collateral load is probably a better definition and these loads are treated
as dead load (except uplift)

Up here, we consider Roof live load as a thing called SNOW (>20 psf) that
will fall right on top of the panels.

Peder Golberg
Portland, OR

----- Original Message -----
From: "Bill Polhemus" <bill(--nospam--at)polhemus.cc>
To: <seaint(--nospam--at)seaint.org>
Sent: Wednesday, November 21, 2001 1:47 PM
Subject: RE: Dead Load or Live Load?


> Okay, let's look at the other side of the argument.
>
> Say the "whackos" win and we have to depend even MORE on solar panels as
> they mothball all remaining electric plants.
>
> Now, suddenly, you as the building owner decide you need BIGGER solar
> panels. So you arrange to have 'em installed, knowing as you do that
> "engineers always design conservatively anyway." Now, your "static dead
> load" has just increased by 50%.
>
> When I was doing plant work, we considered ALL equipment, even if it was
> "fixed," to be live loads for design of buildings, etc. We knew the
> equipment was "here today, gone tomorrow," likely with something even
bigger
> to take its place.
>
> So, anything that isn't part of the structure itself, or the function
> thereof, is "live load."
>
>
>
>
> William L. Polhemus, Jr. P.E.
> Polhemus Engineering Company
> Katy, TX, USA
> Phone (281) 492-2251
> FAX (281) 492-8203
> email bill(--nospam--at)polhemus.cc
>
> -----Original Message-----
> From: Amy Ellis [mailto:EllisAL(--nospam--at)c-b.com]
> Sent: Wednesday, November 21, 2001 3:01 PM
> To: seaint(--nospam--at)seaint.org
> Subject: RE: Dead Load or Live Load?
>
> The definition of dead load is the weight of the structure itself and
> "permanent" attachments.  We consider floor coverings and roof coverings,
> which can be removed to be dead load so why wouldn't we consider
"permanent"
> solar panels to be dead loads.  The solar panels are static loads that
don't
> vary in weight or location. Sounds like a dead load to me - no matter what
> the "environmental whackos" decide.
>
>
>
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