Again, I don't know if this ever went out or got lost with the
list server problems. Here it is, perhaps for the second time, just in
case. And I promise not to speak on the topic again.
If you're interested, the best work I have ever seen on the subject
of comparative steel codes is "Effective Length and Notional Load
Approaches for Assessing Frame Stability: Implications for American Steel
Design" written by the Task Committee on Effective Length of the ASCE
Structural Institute. There are also several papers in the December, 1997
edition of the ASCE Structural Journal. Just remember, this was written by
American engineers who had no interest in performing a hatchet job on LRFD.
You can draw your own conclusions about the viability of LRFD after reading
Canadian limit states design (CSA S16.1) is one of many codes
which use the "equivalent imperfection" approach. It shares a lot with the
Eurocodes and UK/Australian/NZ standards. Only Japan and the USA
continue to use the "effective length" approach for steel design. Effective
lengths are old technology. They have their uses, but the rest of the world
moved on to better things a long time ago. I suspect Japan will leave the
fold soon, leaving us as the only dinosaur.
If you're willing to
make the transition, CSA S16.1 is probably the best around. It is
everything you asked for: Less work, faster, more accurate, saves steel,
and easier to apply to unusual structures. I doubt if anyone who has used
it would ever revert to LRFD. That being said, there is an ASD version of
CSA S16 which is still widely used by Canadian engineers (myself among
them). Both coexist with little debate on the topic. Indeed, it isn't all
that unusual to switch back and forth. ASD for mostly
determinate structures, and LS for the highly indeterminate
I'm also tired of debating ASD vs. LRFD. It is a fools errand.
However, what troubles me is that the debate assumes LRFD is a viable
replacement for ASD. It isn't. LRFD is in bad need of a successor. The real
problem is that AISC isn't working on one.
They both should be
replaced. And the sooner the better. Then I'll switch.