“He was the one ultimately responsible for the building’s flaw and orchestrating the remedy, suffering a crisis of conscience and professional ethics.”. in 50 throws) is 1-(99/100)^50=0.395 (=the inverse of not throwing that number 50 times in a row). In both cases contractors requested design changes, and the engineering firms didn't do a proper review when approving them. Joanne DeCarolis agreed with her husband about the dramatic possibilities of “The Serene Secret.” “I think it has real resonance, especially post-9/11,” she said. By the time it fails, that's 15 jobs ago for the management. It wasn't the contractor's fault, they didn't have the expertise to evaluate whether the change would work or not, and they properly submitted it to those who did. There wouldn't have been a 2 hour "special report" on it. Citicorp Center’s potentially disastrous design flaw stems from the tower’s unusual origins. I've used a PE (Professional Engineer) for exactly that reason - they "sell" trustworthiness, objectivity. Someone who has mod points today and has been involved with a union saw this and went 'how dare you badmouth unions', probably.
The architect of Citicorp Center was Hugh Stubbins, but most of the credit for this building is given to its chief structural engineer, William LeMessurier. I called the Texas licensing board asking how this is supposed to work and the person who answered pretty much said "yeah, you're screwed, unless you've been working as some other type of engineer". There's a reason job hopping is so common in senior management levels. So they built it to the regulations, but the regulations were flawed. Naturally when it did fail it would be at a time when both the upper and lower skywalks were heavily loaded with people, and the floor crowded below.
Actually no, the odds of collapse would be much lower, unless you are assuming that any storm capable of knocking down the building would automatically also cause a blackout that disabled the tuned mass damper that would otherwise allow it to survive. With no support at the corners it seems obvious* that the easiest way to cause a failure would be to apply force directed towards a corner.
The play centers on structural engineer William LeMessurier, who found flaws in the Citicorp Center that would have led to the collapse of that 59-story Manhattan skyscraper. It turns out that she was the student in LeMessurier’s story. You might niot have parsed the summary correctly. I taught on this exact case study for three semesters while attached as a Teaching Assistant to my university's Engineering Ethics course, which had the guy who literally wrote the book on the subject teaching there. I wonder if the emergency generators are in a basement that could flood? To DeCarolis’ surprise, one chapter of the book was devoted to the Citicorp Center (now called Citigroup Center). The DamnInteresting story doesn't even agree with itself, first giving credit to the professor: Uhhh, there was no error, it was wilful cutting costs by simplifying the design by the contractor. While it is true that the bolts were weaker than the welds would have been, they were strong enough to handle the forces the design specified. Can you, as a licensed software engineer, in good conscience release software under any license with such clauses, without totally violating your responsibilities and duties as an engineer? Then he explained how the peculiar geometry of the building, far from constituting a mistake, put the columns in the strongest position to resist what sailors call quartering winds--those which come from a diagonal and, by flowing across two sides of a building at once, increase the forces on both. The play centers on structural engineer William LeMessurier, who found flaws in the Citicorp Center that would have led to the collapse of that 59-story Manhattan skyscraper. ...Pogo dancing was current at the time, and apparently the failure occurred when people on the bridges, synchronized by the live music, were jumping up and down in unison.... Nope. They kept it SECRET so lots can be kept secret? This is less of an issue than you make it out to be. When LeMessurier called the student back, he related this with the pride of a master builder and the elaborate patience of a pedagogue; he, too, taught a structural-engineering class, to architecture students at Harvard. Robertson conceded the importance of keeping the damper running--it had performed flawlessly since it became operational earlier that year---but, because, in his view, its value as a safety device was unproved, he flatly refused to consider it as a mitigating factor. Arthur Anderson was a 100-year old brand worth $9.3 billion. LeMessurier recalls, "I gave him a lot of information, and I said, 'Now you really have something on your professor, because you can explain all of this to him yourself.'". Why not? This may challenge those who are against conspiracy theorists: 'The story you're telling would come out'.
Citicorp center - still standing. In other words, for every year Citicorp Center was standing, there was about a 1-in-16 chance that it would collapse. I've heard news reporting before on this subject. It pretty much just defines the label "Professional Engineer" to mean someone who has passed. About 2 weeks after that, a similar deck to what the PE designed failed, injuring 20. Elon Musk Unveils 'Cybertruck' Electric Pickup Truck, 250 Microsoft Employees Call on CEO To Cancel Police Contracts and Support Defunding Seattle PD, Trump Signs Executive Order Targeting Protections For Social Media Platforms, Submission: The Design Flaw That Almost Wiped Out an NYC Skyscraper, yes, I've used a Professional Engineer. Only the New Yorker story where LeMessurier supposedly talked directly to a male engineering student directly conflicts with the others.
But that’s only if the tuned mass damper, which keeps the building stable, is running.
It took several centuries but they think they've found the body (it was found under a staircase). The 100-year old firm that audited Enron was worth over nine BILLION dollars at the time.
The Fine Print: The following comments are owned by whoever posted them. He believed that the building was safe for occupancy in all but the most violent weather, thanks to the tuned mass damper, and he insisted that the damper's reliability in a storm could be assured by installing emergency generators. I also remember seeing an entire special on PBS about this incident. The cause proved to be straightforward enough: When the instrumentation experts from California installed their strain guages, they had neglected to hire union electricians. if a storm hit every two years, your method would give a probability of 0.393. Copyright © 2020 SlashdotMedia. 45–53. Built in 1977 to house the headquarters of Citibank, it is 915 feet (279 m) tall and has 59 floors with 1.3 million square feet (120,000 m ) of office space.
However, because of the unique design of the Citigroup Center… If this is the case, the building inspectors should have caught it and it was their error.
“The building was supposed to withstand winds of 100 mph or more, but because of those changes, it was in danger of collapse in winds of 70 mph.”. I promised to call back after my meeting and explain the whole thing.". by contrast, the event of a storm happening this year vs. a storm happening next year are closer to independent exactly because the blocks are bigger (a storm on Dec. 31 will make a storm on Jan. 1 more likely, but apart from that...). A new software PE has to be approved by an existing PE, but there are virtually no existing software PEs to approve the first generation. I thought the shredding was technically legal because it was presubponea. Regardless, she didn't find out about her contribution until 20 years later. A system that makes sure a failure doesn't occur a second time is better than nothing, but it's not as good as a system that makes sure the first failure doesn't happen. You are imagining this. Or, as I have seen in person, the grid power comes in the basement, and the generator feeds the basement cutover switch, but they put the generators on the roof, and the fuel on the roof of the parking structure (to reduce fire risk to the building), with a safe and reliable connection between the fuel and generators. Coincidentally, Texas was the first to offer that exam. “The Serene Secret” by Denville playwright Lee DeCarolis will receive a free staged reading at Dover Little Theatre tonight, tomorrow, and Sunday. Once he learned of the flaw, LeMessurier arranged for Citicorp Center to be repaired on weekends.
If you're nearby, maybe I can buy you lunch sometime. Problem was the design had the continuous rod bearing the full load, the change made the upper skywalk bear the load of the lower skywalk (and the people on it) when it was only supposed to be holding up people on the upper skywalk and nothing else. LeMessurier calculated that a storm powerful enough to take out the building hit New York every 16 years." I threw out his plans and re-designed it myself. I got my PE license with the computer engineering test, and I'd happily sign off on somebody taking the software engineering exam.
", No, the "lack of a tuned mass damper" was already presupposing that the POWER was out.
Under normal circumstances, the wind braces would have absorbed the extra load without so much as a tremor. It didn't matter to the buildings being connected if it was done using one support rod or two, from the standpoint of t. structural engineer here. It's now worth a few thousand, because nobody will ever hire them. 114 died, 216 were injured - many seriously.