at those stilts couldn’t sit under each corner of the building, which would be the safest and strongest place to put them.
If they did that, one would basically pierce straight through the new church roof. So, the architect of Cityroup Center, Hugh Stubbins, knew he was going to need one hell of a structural engineer, and he turned to his friend William Lameser. He was known for his quick wit, academic prowess, unbelievable intellect, compulsively detailed, also extremely creative.
He had done some projects such as the the Boston City Hall, which is one of the best brutalist buildings in the US uh was one of his designs. Now affectionately known as the ugliest building on the face of the earth. The City Corp Tower I think was the first major skyscraper certainly in New York that he had done and after um completion of that building his career catapulted in the 70s he was you know pretty much at the peak of his career.
As the story goes they met for lunch at a Greek restaurant and Lameser took out a napkin and sketched the building with the stilts in the middle of the facade. The placement of those columns in the middle rather than on the edge of the building meant the skyscraper would face some pretty significant engineering challenges.
These challenges would have to be solved using things that we might regard today as pretty primitive. The ‘ 70s um is sort of a transition era for structural engineering. Mini computers were available to do frame analysis, but they were expensive and slow. What you have to keep in mind is that, you know, very large buildings up until the 50s were done entirely by hand calculation using relatively very primitive analysis methods.
It was a time when things are changing very rapidly. The building was analyzed using two two-dimensional analyses. One for wind blowing north south and one for wind blowing east west. It was not how it would have been analyzed 10 years earlier, and it was not how it would have been analyzed 10 years later. Now, architects don’t plan out skyscrapers on paper alone anymore.
And as someone who spends quite a bit of time in those towers, that’s a big old relief to me. Now, today, 3D modeling with CAD software is pretty much second nature. But if you’re using anything like an old PC, even opening up some simple editing software could send it into a full-blown meltdown. Which is exactly why we’ve partnered with AMD and their Thread Pro 7000WX series, a processor that’s built for some serious workloads.
It massively takes the pressure off handling demanding software, big design files, and complex workflows with ease. You can generate photorealistic renders, run detailed simulations, and even jump between tools without that dreaded lag. Its highfrequency cores pair seamlessly with platforms like Orus Revit and Metashape, which is especially useful if you’ve just designed a skyscraper on stilts and need to see how it’s going to perform in quartering winds without flattening half a city.
With up to 96 cores of processing power, this thing is seriously hench and built to keep up with whatever project you’re trying to deliver. Guys, you can hit the link in the description or scan that QR code on screen to see how AMD can support your next project. Video sponsors like AMD help us bring you stories like the one you’re watching now.
So, we really would appreciate you going and check them [Music] out. Lamesa would create a series of complicated engineering solutions to compensate for the stilts being in the middle of the facade. Normally, the corners of a skyscraper are one of the strongest parts of the building, but that wouldn’t be the case here.
To address that, the building was fitted with a series of chevron-shaped braces that helped to redistribute its weights. All of the weight of this building would have to be redirected towards the middle using those triangle-shaped braces. Something that may not be obvious to a lot of people, gravity load is not the problem in a very tall building.
lateral load, wind load or seismic load is is where all the effort goes. The system was really a set of uh structurally independent chevrons, each of them eight stories in height and intersected by masked columns uh vertically extending the entire length of the building. And the purpose of this was to basically gather the wind stresses against the building and channel them down through the mass columns down to the bottom truss and into the centrally placed legs at the bottom of the tower. It was ingenious.
The weight of the building would also have to be significantly lighter than that of other skyscrapers to accommodate that kind of structural engineering. It made the skyscraper susceptible to strong winds. So to stop it from swaying too much, a tuned mass damper was installed at the building’s crown. This fully automatic tuned mass damper would counteract any unintentional movements of the high-rise building.
It was kind of unprecedented in New York. It would stop the building from swaying in the wind and creating too much discomfort for those in sight. In general, they’re not used for structural safety. In other words, you don’t count on the tuned mass damper to keep your building from falling over.
What they’re used for is to reduce the motion because that’s what people perceive. And people get very uh upset when when there’s noticeable motion in a tall building. One of my professors, Professor Scandan, had been consulted on the development of that and was able to bring a group of his students up to up to see it. We experienced a bit of a test where they they um excited the damper and then kicked it over into action and it quickly tamped down the movement.
It’s one thing to study things in the classroom and do computer analysis and it’s another thing to see in real life. The officers at City Corp were a bit concerned about the public relations aspect of putting this block of concrete at the top of the building to stop what? Building movement, building sweat. You mean people could get like viscerally sick, you know, from building movement? Of course, tuned mass dampers are now incredibly common in skyscrapers.
The most famous one in Taipei 101 is even displayed for the public to view. Nowadays, it’s pretty uncommon for a high-rise in New York to be constructed without [Music] one. The Messer had done the impossible and solved the engineering challenges associated with the center stilts. The skyscraper rose on the New York skyline and opened in 1977 as the seventh tallest building in the world.
By all accounts, it was a great success. Lamesa even toured the country giving lectures on his engineering ingenuity. Everyone knew even when the building was being constructed that this was something special. This was something new um and interesting on the skyline. But barely a year later, a university student using the building as a case study discovered a terrifying problem with its design.
It seemed to have um uh a lot of aspects that would make for a very interesting thesis. So I wrote up some thoughts and uh approached David Billington and he agreed to take me on as an adviser. um he was concerned because the building was already standing that I might need to delve a little deeper. The engineering team in New York City had been very kind and generous to me when I had approached them.
I wound up taking um a bus or a train up to New York and uh spent a day with the engineers. They were very gracious and they sent me back to school with a complete set of engineering drawings and calculations for for the project. City Corp and the engineering team were at first so enthusiastic of Diane’s thesis, they offered her $10,000 to turn it into a coffee table book once she’d finished.
They were interested in uh leveraging the work I was doing on the thesis. they thought it would fit nicely into their their PR plans. I had left some of what I considered the easier analyses to the end. I was wrapping it up and um went to do the wind analysis, but when it came time to doublech checkck the quartering wind analysis, which I had determined would yield a 42% higher loading.
I didn’t see those calculations. Lameser had taken into account the winds that act perpendicular to the skyscraper, but neglected the quartering winds that would hit the building on its corners. Now, the corners of skyscrapers, as I said, are usually the strongest part of the building. But the corners of this building aren’t attached to anything on the ground.
They just float above it. So, I assumed um I was missing something. So, I do remember making a call back to the office probably a week or two before my final deadline. It didn’t quite make sense to me, but at the time, given my status as a student, um, I essentially just took his words verbatim. I remember being frustrated because I assumed I’d made a mistake and it didn’t make sense to me.
But neither did I feel I had put my finger on something that was any sort of an issue. However, when I got my comments back from my thesis advisor, David Billington, he clearly put his finger on that and said, “Uh, no, there’s a, you know, this is not quite right. The academic course year was over.” And, um, everyone moved on. And obviously if if any one of us had thought it was very very critical, we would have done something else and not just let it go.
She’s certainly not in over her head because the final result was breathtaking. She produced a a 460 page double volume leatherbound thesis with uh 440 endotes. It was a treatise and it was a a complete study of, you know, the cultural, political, and structural ramifications of the city corp tower. So, what about that $10,000 coffee table book? Alas, they never returned my call.
And after about 2 or 3 months, I um gave up and went and got a real job. Who was Diane Hartley to argue with these highly accomplished engineers? So she drops it and assumes she was the one who made a mistake. She adopts the conclusions. She moves on with her life. At the same time, another student in New Jersey, an architectural student by the name of Lee de Carolus, he’s an undergraduate also.
He’s a freshman. He knows nothing other than his professor has said to him, “You need to write a paper and you could probably write a good paper about the city corp tower.” This student reaches similar conclusions thanks to help from his professor. He reaches out to the engineering team for City Corp Tower and actually gets through to Lameser.
He’s in a meeting and he gets interrupted by his secretary. It says there’s a student on the phone. His professor says that the uh columns on the city court tower were placed in the wrong wrong location. and Lameasure bristles, you know, because he’s an academic, he’s a professor, and his curiosity peaks. So, he he leaves the room and he takes the call.
Lameser dismisses the second student’s claims, much like his engineering team dismissed Diane Hartley, except Lameser now has a nagging feeling of dread. Did he miscalculate the engineering? He starts taking some notes and preparing some calculations and he starts realizing as he’s doing the calculations that it’s what he called some very peculiar behavior.
He ran the calculations again and got the shock of his life. Instead of decreasing under quartering wind loads, the calculated load on the steel beams increased by 40%. That’s bad enough, but it gets worse. To save money, the beams were not welded and were connected with cheap bolts.
Less messer only learned of that after the fact. The engineer says, “Bill, didn’t didn’t you know we bolted those? We We didn’t weld them.” the owner was offered a uh $200,000 reduction in price if they went with bolts rather than full penetration welds. So, there were two issues with the skyscraper. Usually, when you have a problem of this magnitude, it’s not from one cause.
It’s there are multiple things added together that that lead to that problem. First issue is the the legs being on the middle of each side and the effect that that has on the wind analysis. If it was just that issue, there wouldn’t have been any need for reinforcing. And the second issue was that these bolts in the bracing system weren’t welded down.
And they weren’t welded down because no one knew about the first issue. The bolted connections were not as strong as the welded connections, but they were still stronger than than the analysis showed was necessary. In the case of quartering wind, the load of the connections would increase by 160%. Lamesa now realized these bolts would not be enough to hold.
A storm like this would also be likely to cause a city-wide blackout, which was common at the time. It would also render the tuned mass damper completely ineffective. Not that the damper would be much use anyway. A storm with winds this strong hits New York on average once every 16 years. That means every year there was a 1 in6 chance that the world’s seventh tallest building could flatten everything around it.
Oh, and they came to that realization just as the city was in hurricane season when winds like this were expected. It really can’t be overstated how much of a disaster this was and how much worse it could get. At that point, he’s faced with the ultimate dilemma. He is convinced it will destroy his career if he discloses. He’s also convinced if he doesn’t disclose, thousands of lives are potentially at risk and therein is the ethical problem that he’s confronting.
Lumeser later stated that he wavered between suicide and silence. He knew that if this got out, not only would his career be over, but there could be mass panic in the [Music] city. He contemplated suicide. He thought on the way home from Maine, “What if I just drove my car into an abupment? I end it all.
I don’t have to deal with this.” He realized that that was the coward’s way out. He didn’t want his children to reflect on him in that light. And so he decided really in an epiphany that disclosure was the only only course of action. He described really having a weight lifted off of him when he reached that conclusion.
There really was no other possibility. It was at that point Lameser realized he had insurance. So he calls a meeting. He has to now disclose to this room full of insurance people and lawyers that uh despite outward appearances there’s a problem with the building and here’s why and here’s what it is.
They tell him that he absolutely has to tell the bank. To La Messer’s surprise, City Corp’s CEO Walter Rriston remained calm at these revelations. They would just have to fix it and quickly. Lameser worked with the city corp higher up to organize emergency repairs on the building. Leslie Robertson, who engineered the twin towers, was called in to assist with a solution.
The actual physical fix was pretty straightforward. If you reinforce the connections in the braces, the those spliced connections, and make them strong enough for the actual forces, then the problem is solved. So the fix was to open up the gypsson board, weld plates onto the onto the braces to to reinforce the the splices, and then put the gypsson board back.
Lameser and Roberts proposed welding 2-in steel plates over 200 bolt connections of the column system. Construction workers welded throughout the night, stopping at daybreak, just as the building’s occupants came in to work. The repairs were kept secret, and people using the building knew nothing about them. City Corpse CEO Walter Rriston as well as the emergency responders agreed not to let the public know to avoid creating mass panic.
The building department was involved with this and they made the decision that there was no need to evacuate everybody around the building unless there was evidence of a direct hit coming and that and the nice thing about hurricanes is you do know a few days in advance. So they would be plenty of time. Carpenters appeared every afternoon at 5:00 p.m.
erecting wooden sheds around the beams. The offices in the city corp center were empty. They didn’t stay that way for long. With the greatest possible secrecy, teams of welders came in. They tore open the wall coverings and concentrated on the steel plates. For 8 hours, they worked to reinforce the columns until several cleanup teams came by at around 4:00 a.m.
By the time the first office staff arrived at 8:00 a.m., it looked as if nothing had happened. The NYPD worked out an evacuation plan spanning a 10b block radius. 2,500 Red Cross volunteers were on standby and three different weather services were employed 24/7 to keep an eye on potential windstorms.
Remember, a collapse of a high-rise building is seared into our minds tragically as a a building that simply falls into itself. In the case of the City Corp tower, the concern was that if one of the splices fractured, they were all going to break and the building would topple. It wouldn’t collapse. It would topple left or right.
It could be a domino effect. It could collapse into other buildings, which could in turn collapse into further buildings, and it could have been an absolute nightmare. So they enlisted the help of the Red Cross, local and state government, and first responders and developed an evacuation plan. But they did the evacuation plan quietly.
They said they were canvasing the neighborhood for some type of survey uh cuz they wanted to know and needed to know how many people could be potentially affected by a problem with this building. And so, you know, the question became, when do these evacuation plans go into effect? There are a lot of smaller buildings nearby and um as as we found out with the World Trade Center, when a large building falls from a a large height, it wipes out everything it hits.
Of course, the welding work didn’t go completely unnoticed, as people could see lights on in the building. A New York Times reporter even got suspicious and called Leser. But before they could dig too deep into the story, the newspapers went on strike and nobody ended up finding out. Things were finally back on track when on August 31st, a massive storm moving towards New York was given hurricane status.
Hurricane Ella began heading for the east coast began veering northward. That’s when the measure said, uh, we were sweating blood. Hurricane Ella was reaching speeds of up to 137 mph, making it the strongest hurricane ever recorded on Canadian waters. The welders had to act fast.
The work couldn’t be done in time for when the hurricane was predicted to make landfall. This was it. Cityroup, Lameser, and the city’s emergency responders prepared to make a public statement and evacuate the surrounding blocks. They would undoubtedly face backlash for keeping this a secret for a full month. The damage to the city would be in the millions.
But at the 11th hour, the hurricane dissipated and didn’t reach New York. The city wasn’t notified and this disastrous secret was kept. The welders finished their work 12 days later and no one was any wiser. [Music] Lumeser is at a dinner party. Life is good. His legacy and career remain intact. Cityroup center is a distant and resolved drama.
The authorities and cityroup agreed to mutual confidentiality and that suited everybody just fine. Feeling comfortable and after one too many drinks at this party, Lameser started to tell a friend about the story. And who overheard it? Joe Morganston, a writer for The New Yorker. He checked out the story and he learned it was true.
Um, so he started making phone calls and uh he got a contract uh an assignment with New Yorker magazine to write a piece that he called the 59tory crisis about the city corp engineering crisis. and uh he contacted Lameasure and Lameasure said I I’ve been waiting for this phone call you know in the one sense dreading it in the other sense happy to have it because now the story could be told the building was safe and Lameasure was able to freely and openly tell tell his story.
The story became public in 1995 when it was published in the New Yorker. It’s funny. I I uh read it while waiting in my dentist’s office. He had the New Yorker in in the waiting room and uh about a week later, everybody started talking about it. What’s interesting is it caused a lot of discussion among engineers, but not so much among the general public.
It was uh I I I was surprised at how little public discussion there was of this. Um in part because it was already 18 an 18-year-old issue. It was solid. After 1995, there was a lot of writing in the technical fields and in the trades uh about what what are the obligations of structural professionals and almost uniformly Lameasure was praised and he should be for his actions here.
But there were some grumblings as well that they should have been more forthright. other engineers could have benefited from the information. Um, if you work in this building, wouldn’t you have wanted to know uh that there was a flaw in this building? At least you would have been given a choice. Apart from being news to the rest of the world, it was also news to the very person who discovered the engineering blunder, Diane Hartley.
And it really wasn’t until about 1996 there had been a a show about the problem, a televised show about the problem. I remember vividly I was upstairs with my younger son who would have been about a a year or a year and a half and my husband was watching this show and he started um yelling upstairs, you know, honey, your your thesis building is on TV.
I went to our bedroom, turned on the television just in time to see um the description of the problem that was discovered and the fact that it was an engineering student from New Jersey. She’s so modest and and humble about all of this. She’s um you know named as you know the savior of New York City and and all these accolades falling on her and she’s she’s uh confused about it a little bit.
It’s surreal and it’s also the fact that it was I was totally unaware at the time that this was all going on. Um, and what’s also surreal and maybe more surreal because I think we discover pro people discover problems every day and you know serendipity. There are things that happen just in the nick of time and I think it’s part of the mystery of life.
[Music] The cityroup tower now stands safely on the New York skyline and has become one of the world’s most famous engineering case studies. [Music] I uh went to some of the younger engineers in my office and I asked if they knew about this and they did. They were taught it as a story of you know don’t let this happen to you and another was taught it in an engineering ethics class.
So it is still being taught to engineers in school. It’s very hard to fault him for anything he did from the moment he found out there might be a problem in my opinion. you know, I might withhold judgment on that because I don’t know um I only know what I’ve read. There’s so many different tellings of the story and having worked in an engineering firm and knowing practices and protocols and and and all of that, I I don’t know um I really don’t know the truth there, but there’s a lot of pressure in the industry. there’s a lot of stress and I
don’t know if that piece of the industry that aspect of the industry is properly supported as it should be. It’s not just every engineer makes mistakes. Everybody makes mistakes and the engineering profession is set up to try to catch mistakes as best we can. But in this case, it was two independent issues that caused the problem.
So there was no one review that caught it. I think most engineers I know, you know, this is the kind of thing we we that wakes us up in the middle of the night. Have I remembered to review everything? You know, part of it is the ethics. Um the fact that an engineer went public with an issue, all of these things, um you know, nothing went perfectly.
It’s human nature. And so I think all we can do as as professionals and and teachers and students is to be mindful of these near misses and try to focus and and get things as right as we can knowing that we’re we’re all human and we will make mistakes. Today we have wind simulation programs and complex computing software to ensure this sort of thing would never happen again.
But it’s startling to think how close this building came to disaster. Don’t forget guys, if you haven’t already, go and check out that link down there in the video description. The AMD Thread Ripper is a seriously impressive bit of kit that could have a big impact on your next project. And as always guys, if you enjoyed this video and you want to get more from the definitive video channel for construction, make sure you’re subscribed to the B1M.
