When designing individual beams, I do it the old way. I still choose the ASD design option out of habit. I do agree with Kootenaykid that the use of computer programs in imperative, and I try to model even the most rudimentary structures, even individual columns with more complex load combinations.
BOLT STRENGTH AISC 14TH EDITION 15TH EDITION MANUAL
I've purchased all of the AISC Manual revisions, read most of them, and really studied the 13th during slow times at work - but still haven't made the switch. Once the load factors were made similar I thought it would be time to finally make the transition, but never quite got there. We were carrying factored and unfactored loads through the system for steel design/serviceability and concrete design and saw little benefit in carrying a different set of factored loads for the LRFD design. At that time I was not thrilled that the load factors were different than those for concrete. I learned LRFD during my graduate work (2000+) and understand its concepts. I was taught both WSD and USD for concrete as the industry was just making that transition while I was in school, and had no problem using USD in practice. I am another old timer that still uses ASD (8th Edition) and don't apologize for it. But my view is that we engineers must always keep learning and growing in our field or we become dinosaurs. We get used to, and comfortable with, certain ways of designing and calculating and after a few years in the business find ourselves sometimes overwhelmed and perhaps even scared of all the new knowledge and technology that comes flying at us from new codes and standards. So many of us loose an edge in learning as engineers. I swore I'd never let myself get that archaic. Never bothered to learn strength design in concrete. Once I worked with an older engineer who was using ACI concrete methods from the late 1950's in 1985. I have a feel for structural behavior whether it is with stress or strength - it really doesn't matter to me.Īnd finally - I've seen over the years many.many structural engineers resistant to change. LRFD, or strength design concepts in ASD, are not that difficult to learn and use. I don't see a significant difference in the resulting sizes unless live load is higher or lower than "typical". I learned LRFD on my own in the early 1990's. I have about 29 years in the business as a structural engineer. 13th edition SteelPE (Structural) 14 Aug 09 16:02 I think there's a place for both methods and both should be supported. You absolutely have to have a feel for the stresses to work with these structures. Structures with low allowable stresses and shapes that havent been made in years. Having done so, ASD is by far my preferred method.Īnd think about existing structures. I understand both approaches (LRFD and ASD). I hear engineers backing the 13th addition from time to time, and almost every time, is by someone from AISC, or in academia, or who doesnt own the engineering business. Good engineers are made as much by art as science. I believe that it reduces the public's safety in that the "feel" factor is removed. I do not like the idea, at all, of taking all of my years of experience in stress, and now trying to redevelope a feel for structures based upon moments and strengths. I agree 100% with being forced to use 13th. I've been a licensed practicing structural engineer for 19 years, and I use the 9th edition. 13th edition Lion06 (Structural) 14 Aug 09 15:29 That argument is settled.Ĭomments? RE: AISC 9th edition vs. What book does your company use? Did you move to 13th edition because you felt you have to because of codes?Īnd PLEASE, don't try to argue that 13th is just as fast. I'd like to know where the typical engineer stands on this matter. When a question regarding 9th edition is posed, AISC ignores that and says to use 13th ed. Using their own publications and magazines such as "Modern Steel Construction, I believe that they have monopolized the conversation. I would like AISC, or another organization, to produce an updated Stress design.ĪISC is still pretending that everyone uses and loves Strength design. We must order steel often before sizes can be finalized and schedules are always critical. Our work in the petro-chemical, offshore, and general industry usually means that time is more important than saving 10% steel weight. My company uses 9th edition, Allowable "Stress" Design and not 13th edition Allowable "Strength" Design.
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