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Re: ASD vs. LRFD

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I studied LRFD as an undergrad and, while I haven't studied ASD
extensively or used it much at all, I can't really see much difference
in implementation between the two.  That is, both seem like they take a
reduction in the capacity of the material, although LRFD effectively
splits it into 2 factors:  gamma (overload factor) and phi (strength
reduction factor).  Apologies to the experts for the nomenclature; it's
been a bit since I studied the names but that seemed to be the essence
of their meanings.  

I think (note the disclaimer!) that the intent of LRFD was to take a
step closer to reflecting the "actual" state of uncertainty (partially
due to uncertainty of loads, partially due to uncertainty of capacity)
from ASD (which seems to be based on empirical design stress limits? 
What is the basis of ASD?  Any good books on the subject?  Inquiring
minds want to know!).  I for one have to agree with the many posts that
have said that as long as students are learning LRFD relatively
exclusively, at some point the number of managers who are comfortable
with either will become large enough that LRFD will become used
dominantly in the field (assuming that it's not replaced before that
with another "new fangled" design methodology...).  

Just my 2 cents,


Charles Hamilton, EIT                   Graduate Student Researcher     
Department of Civil and                 Phone: 949.824.8694
    Environmental Engineering           FAX:   949.824.2117 
University of California, Irvine        Email: chamilto(--nospam--at)