Flags @ Half Mast This Weekend - Leslie Robertson Passes Away 10

[KootK]

EOR for the World Trade Center and one of the best to ever do it: Link.

 

[phamENG]

“Perhaps, had the two towers been able to survive the events of 9/11, President Bush would not have been able to project our country into war,” he continued, referring to George W. Bush. “Perhaps, the lives of countless of our military men and women would not have been lost. Perhaps countless trillions of dollars would not have been wasted on war. Just perhaps, I could have continued my passage into and through old age, comfortably, without a troubled heart.”

What a terrible burden to bear...

An upstart in his early 30s. That's really something. I had no idea. May he rest in peace.

 

[WARose]

RIP.

And really I strongly doubt that had the towers stood, war in the Middle East would have been avoided.

 

[phamENG]

WARose - I agree with you. But it appears that the shadow of that possibility, regardless how remote, hung over him for the last 20 years. Justified or not, it was borne by his conscience, and I imagine the burden was quite real to him.

 

[dik]

WARose... concur... Planned in Germany, by Saudis...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[hokie66]

Thanks for posting that, KootK. I wouldn't have known. The giants of our profession often go unheralded, until a disaster occurs.

 

[Denial]

A big DITTO to Hokie's thanks.

 

[MIStructE_IRE]

Thanks Koot. Being on this side of the pond I regrettably had not heard of Mr. Robertson until now.

I spent an hour last night reading about him and was incredibly disheartened to learn what he went through - what the public and other engineers put him through. What a burden to carry for something that was not his fault. May he Rest In Peace.

 

[DaveAtkins]

I have always thought he was too hard on himself. He DID design the World Trade Center for impact from a plane, which was not required by Code. And the towers stood for awhile--the exterior walls acted as vierendeel trusses for a short period of time. It was the inferno from the jet fuel which ultimately caused the towers to collapse. Not sure how anyone can design for that.

One thing that could have been done better is the design of the stairwell walls. They were GWB/metal stud walls which were destroyed by the planes, thus preventing people from escaping.

DaveAtkins

 

[MIStructE_IRE]

You’re right hokie, Architect’s get the credit - Engineer’s get the blame.

Dave, the cores were no doubt compliant at the time. When costs are being beaten down, as is the case on all projects, all you can do is comply with current codes. Its impossible for anyone to predict what could happen, outside of current guidance, in 50 years time. As an Engineer, I feel very sorry for Mr. Robertson and hope he found some peace thereafter and accepted that this was not his fault.

 

[KootK]

My favorite Robertson building is not one of the mega-talls but, rather, the federal reserve bank building in Minneapolis. It seems to me that the best practitioners of large scale structural engineering possess the confidence to recognize that our tricks and tools are as applicable to the large as they are to the small, often more so. I've no doubt that the building below involved some unique considerations with respect to thermal actions, constructability, etc. At the same time, I suspect that my chicken shit self loses just as much sleep over my two story shacks with offset shear walls as Robertson probably lost over a masterpiece like the the fed reserve building. It's a difficult thing to not conflate the scale of the consequences with the scale of the complexity of the problem. At least, it's difficult for me.

 

[LittleInch]

It's a pity he felt that way.

I've always thought it was a tribute to the design that they lasted as long as they did and allowed so many people to escape.

At the time of design no one could have thought about such a deliberate act with planes that were not designed at the time.

But who now could do what he did at the age and experience??

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[MIStructE_IRE]

That building is certainly a masterpiece koot. Wow! I’m assuming that the catenary (which looks like large steel sections) wouldn’t require any degree of post tensioning and is simply hanging there supporting all those floors? I wonder what the vibrations are like?

What a magnificent structure all the same.

 

[KootK]

I’m assuming that the catenary (which looks like large steel sections) wouldn’t require any degree of post tensioning and is simply hanging there supporting all those floors? I wonder what the vibrations are like?

I ordered Robertson's book last night so, if he's got anything to say about post-tensioning or vibrations, I'll report back on that. I've been holding off on purchasing the book for a while because my gut tells me that it's the coffee table variety and that's not really my thing. Still, if one of our heroes has put pen to paper and there will be no more forthcoming... I'll read whatever he's written.

 

[KootK]

And really I strongly doubt that had the towers stood, war in the Middle East would have been avoided.

When a country like the US wants to conduct a military operation, the primary obstacle to that is usually domestic public opinion. The collapse of the towers removed that, for all intents and purposes, for the time required to set the military actions in motion. In this respect, I think that it is at least plausible that the collapse of the towers meaningfully impacted the course of events. So I understand how Robertson came to feel as he did.

But who now could do what he did at the age and experience??

Firstly, I never met Robertson and can claim no particular knowledge of the man or his thinking. I have, however, spent a fair bit of time studying biographical works in order to try to parse out the nature of leadership and innovation, particularly as it applies to highly successful structural engineers. My impression of things is that many highly successful structural engineers are part genius and part egomaniac, with both parts being necessary ingredients.

When I read about Robertson, I hear echoes of this. The "upstart" designing the world's tallest building in his early thirties and rejecting his partners' suggestions to seek help from more experienced high rise designers. Even the three marriages. My hypothesis on Robertson's feelings of guilt is a product of how I'd imagine myself feeling in his position:

1) You find yourself, somewhat miraculously, with the opportunity to design the world's tallest building even though your resume doesn't yet justify it. Your confidence and ego allow you to accept that task and accept the risks. Or, alternately put, your confidence and ego do not allow you to not accept the task.

2) You get the thing done and it defines your career, spurring it to incredible new heights. You gradually develop, in truth, the resume that would have justified the original assignment.

3) The thing comes down, the consequences unfold like horrific dominoes, and a rational mind is forced to ask itself "Could someone else have done it better? Did I, like Icarus, fly a little too close to the sun in my youthful hubris?".

I don't blame Robertson for any of the fallout of 9/11. I can certainly sympathize with his perspective on it however.

 

[Tomfh]

It’s a mark of his greatness that he shouldered all the responsibility that he reasonably could.

 

[slickdeals]

I attended his movie premiere organized by CTBUH in Chicago in Feb 2019.

Two things that I remembered from his panel discussion that I am paraphrasing.

1. You are not in the business of architecture or engineering, you are in the business of communication. It is extremely important to learn the art of getting your point across with words, sketches etc.

2. As an engineer, you have no business running an analysis model unless you have a sketch of what you are hoping to accomplish and understand load path and behavior.

Les was 93 years old and still active in engineering at the time. I wish I had the guts to go get his autograph.

 

[WARose]

[blue](Kootk)[/blue]

When a country like the US wants to conduct a military operation, the primary obstacle to that is usually domestic public opinion. The collapse of the towers removed that, for all intents and purposes, for the time required to set the military actions in motion. In this respect, I think that it is at least plausible that the collapse of the towers meaningfully impacted the course of events. So I understand how Robertson came to feel as he did.

With respect, I disagree. This is kind of a talking point that got introduced into public discourse by the Truthers. (I am not (by the way) calling you a Truther. I wouldn't call my worst enemy that. ) With the Pentagon hit, Flight 93 going down, and the towers up in flames....I think that was more than enough. (Not to mention the draconian security measures that were introduced afterwards.)

The notion that the towers had to go down also comes from the fact we didn't do enough (to satisfy some) after the '93 bombing of the WTC. But that misses the fact only 6 people died in that. Without any collapse, hundreds died in 9/11. After TWA 800 (in '96) the Clinton admin was looking at it (when they thought terrorists might have been involved) as a possible act of war. So I really think enough happened that day with or without any collapse.

 

[hetgen]

Impressive building/bridge Kootk. Was Mr. Robertson a bridge engineer too?

This is what happens when the enemy (the architects) meets a bridge engineer.

Architect: we don't want to see columns!
Mr. Robertson: Okay, give me two abutments/piers

https://www.lera.com/federal-reserve-bank-mi

 

[MIStructE_IRE]

Great photos hetgen! The link says there’s 16 catenary cables in there somewhere which i can’t see. I’d love to know how they did it!