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The Reasons We Have Codes 14

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JedClampett

Structural
Aug 13, 2002
4,031
For all the griping we do, it's good to have a historical reminder that our work isn't arbitrary and has a reason.
 
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"The concern here in the debate articles I linked to revolves around the theory of how an engineer is either helped or burdened by such voluminous amounts of information. Is it truly information or is it just a lot of burdensome rules to follow that could be replaced by a simpler system."

That neglects an equally important dictum; that a structure should be built in a cost-effective manner. Simplification tends to cause design loads to increase, thereby increasing the cost of construction where something less expensive would fully meet the design requirements for a given locale and conditions. If snow loads are never a problem, then the extra strength required to handle them is unnecessary and costs the builder and owner more than is required.

To say that a code should be simpler is to drive the design to worst-case design, since a lower design point would obviously be insufficient to hnald all possible cases. Worst-case design is very much an old-school concept; it's simple, but brute-force and inefficient. Brutalism meets certain design criteria, but the Crystal Cathedral could not exist in a brutalistic design universe.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
Everything in life is a trade off.

It's hard to argue against accuracy. Yes, our researchers are providing the industry with more accurate science. This research leads to more complex (but more accurate) procedures, which then become adopted into newer versions of codes. The codes grow and grow. This doesn't surprise me after all, who is against being accurate?

We should, to a point. An engineer's job isn't to be accurate -- it's to make decisions. And lots of them.

Engineers need to make countless decisions on a single project, let alone their careers. Should the wall be 18" or 24" thick? What's my load path? Will this material selection satisfy the fire provisions of the code? Is my edge of slab 1'-6" or 1'-10" along this column line? Do I have enough budget? Do I have enough time?

Experts have learned how to make decisions. Sometimes, you need to run a thorough and time consuming analysis. Other times, you need to discuss the issue with several peers, offer assessments, solicit feedback and use that perspective to decide. But most times, you just need to rely your gut and keep moving.

"Expertise" is shorthand for "my intuition and memory have been calibrated by so many years of conscious thought and experience that it's all one system, working together." That's powerful stuff. Our subconscious is where our real horsepower really lies...and it takes time and effort to build a root network into it.

We need to value what it means to be an expert. It's our calibrated intuition. It's our ability to make decisions. It's our ability to then communicate those decisions to a wide audience. It's not our ability to compute accurate answers. Heck, that's what computers do.

So every time we uproot our previous understanding in a favor of new, marginally more-accurate ones -- it costs us something. We can't rely on our intuition while we are reprogramming it with the new understanding. That takes time and effort. Meanwhile, our ability to quickly make decisions is short circuited -- and projects, clients, and our bottom lines suffer.

Codes are here to protect the public -- what's the best way to do it? Do you allow engineers to nurture their expertise based upon their current understanding so they can deploy it to make thousands of thoughtful decisions on thousands of projects that affect thousands of lives each day? Or do you force the entire profession to unlearn and relearn by tinkering with the codes so it takes a dozen pages to calculate a wind pressure of 24.31 psf when one page that yields 25 psf would lead to the same decision?

Everything in life is a trade off. My gut tells me that we should argue against accuracy more than we have been. Expertise is valuable.



"We shape our buildings, thereafter they shape us." -WSC
 
Does the code state that I must use those calculation methods? Am I (say as a registered professional structure engineer) allowed to substitute my experience and determine a design on that basis alone, rather than actually sing those numbers, calculating some wind load force and calculating some beam size?

I would tend to use experience in lieu of calculated wind loads if possible. For example, I generally don't do much actual mathematics for a low pressure, small diameter, buried, steel pipe operating at typical ambient temperatures, simply because I know MY resulting design will be more than the minimum requirements of the code, but not excessively so. I would not do a pipe stress analysis to verify that conclusion, simply because I know that a simple note to the design documentation stating that my professional opinion as an experienced, registered engineer is all that was required and that is all that is legally needed in my state to show that it is sufficiently verified.

Are you still allowed to do that?

Reaction to change doesn't stop it :)
 
BigInch --

In the structural world (or at least my niche, major bridge demolition), yes and no.

We're increasingly coming across owner's agencies who are requiring "extraneous" analyses as part of their approval process -- checks that we have deemed through experience, observation, familarity with the project, (etc) to not be applicable or to affect the design.

Most often, when we dig into it, we find that the requirement is not being driven by the agency themselves, but a consultant who has been brought on to review our plan. Ironically, even though we are also finding that owners are requiring more and more specific experience to be the EOR on these projects (which works for us, we have it), the review consultants often have little or no relevant experience. I suspect they are chosen more on the basis of having an existing relationship with the owner.
 
Yes. If they're willing to pay for it, no worries.
If not, sometimes the hardest decision you have to make is who not to work for.

Reaction to change doesn't stop it :)
 
Wow, I hope they had the medical insurance forms filled out:

"Faultless Healthcare Linen's chief operating officer, Mark Spence, told the St. Louis Post-Dispatch the three victims there were new hires who were filling out paperwork when the boiler came crashing down on them, killing two and injuring the third."

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.
 
The reason we have codes is viruses, just viruses, plain and simple.

Mike McCann, PE, SE (WA)


 
Needless government regulation?
In 2008 a seat belt and an airbag and a crumple zone in my compact car all functioned as intended and saved my life.
General Motors fought mandatory airbag laws in DC for 15 years. For this reason (and others) I will never purchase a GM product.

"If you don't have time to do the job right the first time, when are you going to find time to repair it?"
 
I'll never purchase a new GM product because of their past mismanagement. Or maybe the two are the same thing?
 
Then you're missing some truly fine and well engineered products. Exactly what was is about "their past mismanagement" that you are so upset with?

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
What makes you say that GM is managed any worse or better than any other company, such as, say, VW?


STF
 
John, I believe that Cranky is boycotting GM because their management's disregard for safety. "General Motors fought mandatory airbag laws in DC for 15 years."

BP's on my boycott list (since 2004).
Amazon (since yesterday).


Richard Feynman's Problem Solving Algorithm
1. Write down the problem.
2. Think very hard.
3. Write down the answer.
 
"management's disregard for safety"

That might well be every car company. Ralph Nader's "Unsafe at Any Speed" covers some of that:
Ford has had issues with Pinto and Bronco, at the least.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
Are there seat belts in school busses today?

Richard Feynman's Problem Solving Algorithm
1. Write down the problem.
2. Think very hard.
3. Write down the answer.
 
Some of you may not remember them, but cars from American Motors were the first with seat (lap) belts and self-adjusting brakes. They led the industry in several innovations, both safety and otherwise.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
And as I remember the Ambassador was the first car with standard air conditioning. This was quite radical in its day (1964 or 1965).
But look where they are now.
 
We've owned three American Motors cars, the first was a 1965 Rambler Classic...

1965_Rambler_Classic_srakig.jpg


...that I bought two weeks before we got married (which BTW was 50 years ago this past Saturday) because my future (and present) wife refused to go an our honeymoon on the back of a motorcycle. BTW, it came with front seat lap belts.

Our second AMC vehicle was a 1968 Javelin...

1968_Javelin_g28mho.jpg


...which we had while I was in college and which I used when racing in road-rally's (I was always the navigator, but my driver and I alternated cars when we raced).

And our last AMC product was a 1973 Matador...

1973_Matador_yynkff.jpg


...which was the first car we had with AC and an automatic. And it was a hot-rod, with a 360 cubic inch V8, four-barrel carburetor and duel exhaust. This was also the first car we drove cross-country (Michigan to Washington State).

I replaced it in 1978 with a Ford E-150 cargo van, which I converted into a basic RV configuration since we did a lot of long-distance vacation road trips. By then my wife was driving a Mercury Cougar.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
Actually I was talking about the GM bankrupt/bailout. That was mismanagement.

What about the AMC pacer?





 
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