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Trying to explain to non-engineers that it may be OVERKILL, but it is NECESSARY 38

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matty54

Industrial
Feb 10, 2022
65
I constantly here non-engineers complaining about how everything structural engineers design is so unnecessary and overkill. It is hard to explain to someone unfamiliar with design codes and engineering theory why certain members need to be sized the way they are sized even if using a smaller member (or no member at all) would not cause the structure to fall down.

I am wondering if anyone has had any discussions with members of the non-engineering community around this topic, and how you explained to them that the seemingly unnecessary sizes of the components are indeed necessary.

My personal explanation includes three main reasons. Please add to this if you have more.

1) Proof
any design that you come up with, you have to be able to show or prove what the forces in the members will be. and If you don't have all the information to start out with (ex. proper loads) then you have to make educated approximations of this missing information that will almost always be conservative. People always say, "it's not going to fall down, it's common sense, just look at it, others were built just like it and they are still standing". But if you can't prove it through applied scientific principles or scientific models, you can't just say its fine no matter how overkill it looks.

2) Time
For most of the designs that I work on, there are very short timelines for projects. These short timelines mean that there is not enough time to do proper analysis on the entire structure so some vary broad assumptions get made. And the broader the assumption, the more conservative it has to be. The less time that is available to analyze, the more excessive the design becomes

3) Code
Specifications like the ANSI/AISC 360, CSA S16, ACI 318, CSA A23 which get incorporated into building codes specify exactly what strengths you are allowed to assign to members. Given that inelastic and plastic analysis is allowed to be used, time often only permits the use of linear elastic analysis in my case. This is one item that always gets brought up. In a linear elastic analysis the member fails, but in reality the forces will be redistributed throughout the structure to different members. If you don't have the time, tools, or expertise to do more complex analysis, and you are stuck with first order linear elastic, you can't rely on the force being redistributed, because you can't show it.
 
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Lomarandil said:
Mass timber will get my support as environmentally friendly when they stop cladding it in glass to show it off and burn all the benefits in heating and cooling costs.

That's a fine point.

I honestly think that much of the perception of "wood as good" comes from everybody just generally being fans of trees. I recently read a book that has given me newfound disdain for trees: The Ends of the World. Apparently, the original trees over colonized the earth, pulled all of the C02 from the atmosphere, triggered a massive ice age, and nearly ended life altogether. Selfish.

So to hell with trees I say. Once you view trees as your enemy and look at them up close, they're actually pretty ugly. Who would want to wake up with one of these next to them in bed? Nobody, that's who.

C01_d1czjz.png
 
@matty54 At my last job I was lucky enough to have the support and respect of the big boss, which was crucial, but that did not translate into having support from anyone else in the business. Getting "regular" people on-board with trying to get things better organised and approved was my long term objective. In my view, that starts by building relationships with those people. Everytime I had to interact with someone new, I always took some time to go and see them in person to joke around and listen to everything they had to say. Almost everyone has at least a nugget of useful information / good idea about how things should be done. When trying to implement a new way of doing things, they would often then ask if some other way also possible. I always tried to make time to actually take into account what they were asking and see if we could incorporate some part of it into the original plan. If you are actually able to help better organize and help regular people in the business, while painting a picture of a future when thing will run more smoothly, this will translate into extra influence to help you turn things around.
I think the days of the engineer commanding respect with his title are long gone (if anything it's the other way around now), so reputations must be build from the ground up with demonstrations of compromise and competence.
 
One of the hardest lessons to learn is that there are good clients and companies to work with and then there are the ones that you shouldn't. Flying with turkeys will take you down to their level. Don't go there. If you get caught in that net, cut your way out. It just gets worse until you do. A promise to change for the better usually doesn't ever materialise into reality. They got wherever they are without it and change is hard work. It typically takes a dramatic event (major disaster) to happen before they get to the serious change committment phase and realize they must do it to survive. Even then, it may not happen. Very few companies have actually managed to pull it off. I worked with 3. Left before the disasters caught up with 2 of them, but they did. Were related to fraud; financial disasters, and were completely Bankrupted. All pensions lost. Nobody killed directly, but there were a few suicides. One other built things reasonably well, and still does, but was not entirely ethical, often violated code and exploited many of their employees and had no intention to change. Just not a nice place to work. There are great clients and companies out there. Just takes some work finding them.
<You have been warned.>

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."
 
Engineers design to the requirement of the code. If they don't like the criteria that all engineers, contractors, & property owners, are required to meet, have them take it up with the state.
 
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