Thursday, January 23, 2014

Structural Engineering, Computers and Commitment

‘[W]ith the ready availability of powerful computers and highly efficient structural analysis programs, an engineer possessing sound knowledge of structural form and behavior should be able to device and analyze a structure to suit a building of almost any conceivable irregularity’ From the book Tall Building Structures – Analysis and Design by Bryan Stafford Smith and Alex Coull
When I read the above lines in a book on analysis and design of tall buildings, I was transported to seventh heaven. It was a “Beam me up, Scotty…” moment.
The sentiments espoused or implied in the above is what I have beaten my breast about to recent entrants to the profession of structural engineering, of which I consider myself to be a part. But, for whatever reasons, what I say comes off as demagoguery or a harangue, easy to be dismissed or at least brushed under the carpet. When I assemble a group of youngsters to explain certain fundamentals that have either skipped them or they have already forgotten, their reaction is a Grand Canyonesque yawn. “We’ve been there, done that”.
But, when shown that even if they had known what I am telling them, it is time for a recap, they tend to feel I am talking down to them. Rest assured I am not spending time, mine and theirs, to show I am one up on them. It is just that they have a duty to their profession, particularly if they want it to help them keep themselves fed, clothed and sheltered, and that commitment flows through these basics.
The above is the context in which I felt elated upon reading the opening quote of this post.
I want to parse the quote, phrase by phrase. First, I take up, “the ready availability of powerful computers and efficient structural analysis programs.” I am very happy that the changes in how structural engineering is being practiced from a couple of decades ago are acknowledged; very few, if any, engineers use their earlier day’s bread and butter, the slide rule, or even calculators. They have their Excel sheets, besides the specialist software. But …
Yes, there is a twist to my feeling happy. Yes, I want the computers and software to be available to the engineers, but, not too readily. I am neither a Luddite nor an old fogie who feels most comfortable with the tools of yesteryears. I have tried to, and have succeeded to some extent, to keep myself abreast of the new tools of my trade. I appreciate how things have made the life of a structural engineer easy. I do not begrudge that the youngsters are a million times better and faster than I am at working the software. This is Father Time working his way and I respect him for that.
But, to use an old phrase, before the time of GUI, “GIGO” – garbage in garbage out. Perhaps with GUI, the “garbage in” phase has been taken a level deeper. It is not the numbers you input into the computer that nowadays spews out garbage. Rather it is the model you have created that does it. The model is in danger of carrying much less fidelity to what the engineer wants to do, but he is not aware of this disconnect.
I blame the “ready availability” part of the phrase. The 3-D model on the screen overwhelms the engineer instead of illuminating her ideas. The siren song of accelerated output does not fully compensate for the advantages of comprehension. The “readiness” aspect should factor in how ready the engineer is in comprehending the structure and her work.
This leads me to the next phrase I want to focus on: “possessing sound knowledge of structural form and behavior”. In structural engineering the form of a structure plays a major role in how it behaves. Understanding this interrelation is what I would call “comprehension”. So, we now come to the preparedness of the engineer. During studies for graduation, the engineer is taught no more than the truly basics of her profession. When he comes into the field he is deluged with details that he had not of heard of before. Setting things right demands commitment from the graduate.
It goes beyond doing your job well in the profession. It depends on using one’s own time – the time for which one is not paid – to take an interest in the chosen field. I know a few engineers who exemplify this attitude and also aptitude; but, alas they are far too few if the profession has to develop in the country. Such extra-curricular, for want of a better word, commitment is what gives the engineer a “sound knowledge of structural form and behavior”.
This is what I tried to infuse in one of my lectures wherein I showed what looks like a slender column but the designer choosing to call it a shear wall. I asked why. This was a classic case of a form and behavior fusing with each other, the name giving the clue for the fusion.
The next phrase, “should be able to device and analyze a structure.” Note the level of commitment, a mere “should be able to.” That is, sound knowledge alone may not be sufficient. There is something called intuition. There is also value to real life experiences, if only the engineer is equipped to draw parallels.
This I tried to exemplify in one of my brief presentations, on “punching shear”. I took the shards from a punching machine and showed that all of them were cupped rather than flat. I explained why, going beyond the obvious fact that the punching surface was concave outwards, and also its relevance to the topic under discussion. But there were few takers.
The engineer has to be able to visualize the forces coming onto the structure and “feel” the structure responding. No amount of immersing oneself in equations or clicking on the icons is going to help in this. One has to eat and sleep with the structure and in a manner of speaking, mate with it. This obviously takes time. One has to court the profession, get married and then feel fulfilled.
Yes, all these thoughts coursed through my mind as I read the paragraph. Now, you may agree why I felt so elated.
Raghuram Ekambaram
P.S. I have written the above from the perspective of a structural engineer. However, I suspect, one can draw parallels in any field of engineering.


P K BANSAL said...

I have read your thought on use of computers in structural engineering field, i fully agree with your views. I would like you to guide us regularly on the basic guidelines.

P K Bansal

mandakolathur said...

Thanks for the appreciation which encourages me. I have tried to do my best, but it has been an unequal fight and I have accepted my defeat. It will be impossible to restart with the same enthusiasm. My apologies.