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LRFD Load Factors

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This appears to be a subject that has varying opinions. For what it is
worth,
here is mine:

Different cultures will use buildings in different ways. While one may
feel it
is OK to put no more than 100 people in an assembly hall and will
enforce it to
that standard, another might feel it appropriate to have 300 people or
more in
the same room with no enforcement. If the load is adjusted to accomodate
this
difference then the load factor will not need to be. However, the load
factor
normally accomodates the probability of overload and this can be
different where
enforcement is lax and the culture has different traditions.

The phi factor is used to cover variations in material and construction
quality.
This definitely varies from country to country. There may be much more
variation
in concrete and masonry construction than in steel, but this also
depends on
many things. Is the steel imported? What standards does that country
have? How
much independent inspection is there on the project? Is there a greater
probability of mistakes  getting hidden or overlooked? Is field welding
up to
the same standards as AWS or AISC?

I believe the engineer needs to adjust both the load factors and phi
factors to
accomodate those differences outlined above. How that gets done, I am
not sure.
This is an area that obviously needs some study.

Jim Kestner, P.E.
Green Bay, Wi.