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RE: DEFINITION: "Full-Factored Live Load

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Bill,

It's true, factored unreduced live loads is not full-factored live loads, 
but how can you get partial-factored live loads, or half-full-factored live 
loads?

If you look at ACI 318-95, section 8.9.2, the hyphen is left out and this 
section of the UBC is supposed to be identical to ACI except where italicized.

Anyway, the way that I would read it would be as "factored unreduced live 
loads."  (I debated whether to put a comma after "factored" and decided to 
leave it out!)

A. Roger Turk, P.E.(Structural)
Tucson, Arizona

Bill Polhemus wrote:

. > But how is that "full-factored"? The hyphen is, I think, significant.

> -----Original Message-----
> From: Roger Turk [mailto:73527.1356(--nospam--at)compuserve.com]
> Sent: Monday, May 03, 1999 1:21 PM
> To: seaint(--nospam--at)seaint.org
> Subject: DEFINITION: "Full-Factored Live Load" in
> 
> 
> Bill,
> 
> I would read this as you can't use the reduced live load 
> (reduced based on 
> tributary area).
> 
> A. Roger Turk, P.E.(Structural)
> Tucson, Arizona
> 
> Bill Polhemus wrote:
> 
> . > Funny how your assumptions sometimes don't bear up when 
> you actually
> . > scrutinize them.
> 
> . > All along, I was assuming that live load "patterning" for 
> analysis and
> . > design of R/C buildings included use of such patterning 
> when lateral 
> . > loading (such as wind) was part of the analysis.
> 
> . > However, I'm unsure about what to make of the referenced 
> paragraph.  For
> . > those without a UBC handy, I'll quote:
> 
> . > "1908.9.2 It is permitted to [assume] that the 
> arrangement of live load 
> . > is limited to combinations of:
> 
> . > 1. Factored dead load on all spans with FULL-FACTORED 
> live load on two
> . > adjacent spans, and
> . > 2. Factored dead load on all spans with FULL-FACTORED 
> live load on 
> . > alternate spans."
> 
> . > [Emphasis mine].
> 
> . > Now that I read it, it seems to me that "full-factored" could be 
> . > interpreted as meaning "the greatest-factored live load," 
> i.e. 1.4D + 
> . > 1.7L, and that live load in all other combinations [e.g. 
> 0.75 (1.4D + 
> . > 1.7L + 1.7W)] need not be subjected to "patterning."
> 
> . > Am I wrong? If so, how do you interpret this, and how do 
> you accomplish it
> . > in your analysis?
> 
> . > Thanks.
>