Structure Mag......Code Article 15

"Experienced engineers (5 to 40+ years) produced design wind forces that varied from 3.9 kips to 24.2 kips with a standard deviation of 42% in the results."

This agrees with what I have been figuring for some time now based on seeing other engineers work. I know I have unintentially missed things as well. All the west coast engineers seem to be currently having a hard time adjusting to ASCE wind, but seismic is even worse to me-especially getting all the special detailing right.

"Why have we as practicing engineers allowed the codes to become so complex? I propose the single biggest answer is apathy"

I agree with this one too, and apathy seems to fit our fees as well. But I am also guilty on the code part because I have never been to a committee meeting on anything and argued for simplification. A good one would be, why now does it have to take 4 hours to design a couple of anchor bolts by hand?

http://www.structuremag.org/Archives/2007-12/D-Editorial-Nuttal-Dec07.pdf

 

[DRC1]

Great post!

It seems every year specs get thicker and thicker or more and more complex. AASHTO is the worst. I think the latest volume may excced the allowable floor loading for my office. AISC has not gotten that much thicker, but has required more sophisticated analysis. I think that software companies and acdemics have convinced code writers to require very sophisticated models but the computational means are there. Although this may sound good in theory - if we can make more exact models, why not?, We now have codes that require the use of programs that we can not touch by hand. More and more engineers absolutely need a computer to solve problems. Ask for slope deeflection or moment distribution by hand and they look at you blankly.
Now even the wind load codes are so complex, they aparently can not be solved by hand. There are a lot of structures designed by hand to simple understandable models that have stood the test of time. Not that every model needs to be solved by hand, but such models shoud not be eliminated as they reinforce our understanding of the actual load and response. I saw the article - it is really good. the entire magizine is quite good.

 

[bridgebuster]

Ditto about AASHTO

I took some measurements:
1953 AASHTO 6th Edition 6"x9"x 3/4" 40.5 In^3
1973 AASHTO 11th Edition 6"x9"x 1 1/8" 60.75 In^3
1996 AASHTO 16th Edition 8 1/2"x11"x2 1/2" 233.75 In^3
2004 AASHTO LRFD 3rd Edition 8 1/2" x 11" x 3 3/4" + 2 1/2 " of interim specs 584.38 In^3

Perhaps the paper companies are in cahoots with the software writers and academics.

 

[HgTX]

The author is right. I see lots of griping about the complexity of the codes, but how many have you have ever plotted out the curves from the fancy equations, come up with a simpler approximation, and proposed a change to the code?

Hg

Eng-Tips policies: faq731-376

 

[vincentpa]

The complexity of the code is outrageous and the code cycle is even worse.

We need to rise up, in arms if necessary!

It is just impossible to do things by hand and be profitable. I am a relatively young engineer, 35. I prefer to do things by hand when I can just to understand what I am doing. But, to turn a profit, it is really difficult these days to do that. I barely remember how to do indeterminate structures by hand. Just designing a simple shear connection by hand would take too long with these budgets. The young engineers now are just computer jockies. That's a shame. First AutoCAD released the young engineers from the board to our detriment. Now the computer is releasing the young engineer from theory and the design itself. We just interpret results and draw details. For bridge engineers it is even worse. They don't even draw details. I did that for 3 years. I had to get back into buildings because i didn't feel like an engineer anymore.

The codes have increased our effort while our fees are decreasing or are stagnant. There is a shortage of engineers yet our fees don't obey the law of supply and demand. The architects and state DOT's have us by the you know whats. With the architects, things might change with the new generation (my generation) but I am not too optimistic. The state DOT's will never change.

One reason the codes are more complex is that professors need to justify their research projects. They want to see their name published and they lobby the code committees. Many of the code equations are based on one research project. That is ridiculous. We need to infiltrate the universities and make changes. I'll never let my child be an engineer. I love the work but why take on this much stress and responsibility when they can be a dentist or lawyer and make 10 times as much, literally.

 

[HgTX]

Great. Draft a proposal for specific changes and submit it to the relevant code committee.

I do this frequently. I get my way a lot of the time.

Code writing is a "do-ocracy". If you're willing to do it, you stand a chance of getting what you want. Otherwise, put up with it. Bitching about it in a forum, saying, "Oh me, oh my, surely something must be done! Those eevul perfessers! Those scurvy knaves at the DOT!" accomplishes nothing.

Hg

Eng-Tips policies: faq731-376

 

[UcfSE]

It is not the computer's fault for what is going on. The computer is an awesome tool that makes possible the great things we can accomplish "for $1 that any idiot can do for $2". Maybe we can start doing things for $0.75 instead of $1.

The fault lies with lazy, ignorant, arrogant, naive young people and complainy, lazy, arrogant old people. Young engineers should have the brass to learn something for themselves and older engineers should have the courtesy and foresight to point them in the right direction. Otherwise all you have is young pups listening to the Alzheimer's unit complain about new-fangled techonology and talk about going uphill both ways to school. That's not productive at all.

There seems to be a lot of that lately among the older generation in the trade publications. Too many gray and blue hairs crying about the younger generation and not enough turning that criticism inward.

Note that this is not every young person, and not every older person. that seems to get left out frequently. Let's not get into stereotypes if possible. I exaggrerated to make a point only.

How many here plan to participate in the trial design problem mentioned in the article?

 

[haynewp]

I will do it.

 

[vincentpa]

HgTX,
I don't have the time to run committees. I can complain anytime I like to whomever I like. Everytime I go to a seminar that is hosted by a committee member, I complain and make my concerns known. I'm glad you have accomplished things with your letter writing. I never have. I've sat on three DOT committees in grad school. Nothing get accomplished except by those with an agenda. The committees are usually driven by a couple of stubborn people that don't back down and they usually get their way. I can't bear the cross for this profession in the fight to make it better. It is broken beyond repair. I will just make sure my children don't make the same mistake I did. Do what you love. That is what they tell you. Only when you're older do you realize that work is only work and that money DOES make life a lot easier and more enjoyable. Thankfully, I married a dentist.

 

[Gumpmaster]

Interestingly in the same edition of Structure magazine on page 45 is an article titled "Code Changes Affecting Post-Installed Concrete Anchor Design". The article espouses how much better ACI Appendix D is than previous design methods because it rewards the engineer by "increasing the efficiency of the system" and provides "additional transparency".

These two articles are pretty much in direct opposition. ACI Appendix D is one of the most complex codes I've seen. I thought it was pretty funny that both articles show up in the same edition.

 

[BigH]

I am in full agreement that the profession (Journals, PDH requirements, etc) are being driven more by academia and those who see pots at the end of the tunnel (look at the ASCE Geotechnical Journal for example) and in any issue I would bet (I've counted several issues) where the professors (or their grad students who happen to have graduated and just took up a job in industry) comprise more than 90% of the authors. I have taken the time to point out a few edit errors to AASHTO - and what did I get in return? An under the belly blow in return. Years ago I had asked how I can report the cylinder break to the nearest 79 kPa. Mmmmmm

 

[connect2]

vincentpa,
Way to go, love it. Unfortunately I didn't marry a dentist. Anybody looked at the EuroCodes and related info lately? Wow's all I can say. It's a wonder anything is standing!

 

[Bobber1]

And what's with all the errata? Our designs have to be significantly error-free if they are to be safe. Can't the code writers get it better?

 

[vmirat]

Funny how things tend to come back around. I posted a similar issue under thread507-165041. It would be interesting to compare what people had said then and what they are saying now.

 

[HgTX]

Nope, it's just a re-run.

Hg

Eng-Tips policies: faq731-376

 

[connect2]

vmirat and HgTx;
Same thread, scares me when I see myself in the same discussion from another thread because it often depends on the day I've had and the # of beers I've had when I get home before I open up eng-tips.com to see whats up in the world of structural engineering. Yes little has changed vmirat since your post, your gracious ending to it was well appreciated. It allowed me to could go to bed and look forward to the next day. It's not all crap and crazy, some interesting things going on. Just wish I had more time and money. Applied Physics and Mechanics, very cool!

 

[BRGENG]

In order to justify their research, College Professors need to have their research referenced by the building codes. The easiest way to do this is to join one of the many building code, ASCE, ACI, etc committees, Professors have the time compared to practicing Engineers that don’t. Then they can get their equations in the code that have at least three roman characters, 3 separate equations to find a value, one of which must have two separate equations and take at least 10 times longer. In the end the final answer is within a percent or 2 of the original method that took 5 seconds to calculate.

Remember IBC was heavily criticized for the increase in lap lengths for masonry construction. Is it any wonder that the lap lengths are long enough to justify mechanical splices and that fact that over a third of the committee that approved the changes was from the mechanical splice industry?

I served on a small ACI 318 committee. I was amazed at the number of proposals I received from the construction industry to push for their products to be included or ban their competition. The typically committee consists of 1/3 Professional Engineer that practice engineering, 1/3 Professors and 1/3 from the industry. Since they have a hard time getting real Engineers to sit on the committees they are often replaced with professors that are PE’s or industry salespersons that are PE’s. You will get a lot of I’ll vote for your item if you vote for mine.

The changes would not bother me if we had failures or faulty designs. Have you seen a correctly engineered and constructed building fail under code loads? The majority of failures I have investigated are the results of one of the following.

1) Water
2) Lack on maintenance or age of building
3) Bad construction
4) Extreme loading conditions well beyond design values.

My old steel professor explained it best to me many years ago.

We had researched everything we could with ASD and had nothing left to research. So the best thing to do is come up with another method and research it all again. Hence you now have LRFD, Laboratory Research Funded for Decades.

Look at the new AASHTO code, over 1500 pages. It doubled in size when it went to LRFD. Has that much really changed?

ASCE, which many of us are members of and pay them over $200 a year. They are now one of the largest providers of Continuing Education, their committee members make thousands educating us on why the SL or WL have changed yet the answer remain the same. And ASCE pushed to make CE required for professional engineers, do you wonder why? Now they are pushing to make a M.S. degree the first requirement for obtaining your P.E. license. Why not, most ASCE committee members are professors and they will see their Grad. school enrollment sky rocket. I’m glad retirement is around the corner, maybe I will teach in my old age. They could probably use a Professor for all the new grad students.

 

[Lion06]

Star for BRGENG.

 

[JLNJ]

What we need are some more load combinations for wind. Four for each direction is not nearly enough.

 

[Lion06]

Yeah, the wind load cases are crazy. When you run a code check in RAM Frame, it generates somewhere in teh neighborhood of 168 load combinations! How in the world do you do that by hand?