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Re: LRFD Load Factors.

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The long and short of the answer to your question is technically IMHO .....
no.  In Jamaica we use primarily British Codes (Limits States = LRFD),
however depending on the source of funding for various projects, we may end
up using American, Canadian or British CP.  The Load factors as you
rightfully point out are geographically, and environmentally specific (eg.
How rigidly are local statutes enforced with regard to No.s of ppl in a
dance area, allowable axle weights etc), the resistance factors (partial
factors of safety), are another matter, especially as it relates to
concrete, and timber (ie materials which tend to have less quality control
than say steel).  The final point is Load Factors, as presented in the codes
are essentially guidelines, and do not serve as carte blanche figures to be
applied, because at the end of the day what governs is engineering judgment,
as sound as we can make it.

I don't know what the construction environment is in Peru, but I do know
from at least a Jamaican perspective, what applies here, I know is quite
different from what the CP envisaged.

Additionally, modern CP's (Code of Practice), are also related to expected
levels of risk (I'm not sure of the specifics of the American Code) which
are related to expected return periods (eg 1:100, 1:25, 1:50 etc depending
on the CP). ( I'm not sure I agree with the premise, because a 1:100 yr
event can occur in year two .. explain that to a client, but that's another
discussion altogether :-)).

These are all things which I think need to be borne in mind, when using the
CP out of it's intended environment (and to a degree, even in it's intended
environment).  The quick answer after all of that verbiage (IMHO) is use the
provided values as guidelines and adjust up (or even down) as you can
reasonably determine, in lieu of hard data (if it's available .all the
better :-)).  What we do, is however, as a project is ongoing we
statistically analyse available data (cube, cylinder tests etc), and examine
how close the values are to the expected figures and reanalyse the system

I hope I've been more of a help than a hinderance

Maurice J. Allgrove, PE