Talk:Construction of the World Trade Center

FA milestone
1400th FA Buc 20:41, 22 May 2007 (UTC)

Geotechnical work
I can't believe I'm the first to talk on a FA page; how did it make FA without discussion? Anyway, I am wondering if the author(s) have any sources which describe the geotechnical work of the project, notably, the foundation. The fact that there is a foundation and that slurry walls were used in construction are mentioned, but as a geotechnical specialist, I think a few more details would make this article more comprehensive, like the type of foundation. I was not able to find anything useful in the references I looked in, but if you have something I missed, I would be happy to try to write a few sentences on it. Basar 08:19, 10 July 2007 (UTC)
 * About all I found was:


 * George J. Tamaro Jr., P.E., F.ASCE, H.ASCE...was the fellow who engineered the slurry walls.
 * Most of the rest I saw were related to the reconstruction of the existing walls.--MONGO 09:51, 10 July 2007 (UTC)
 * Some detailed sources on geotechnical aspects may be available. Though, I'm pretty sure they require someone going to a large university library and looking through old journals and possibly material on microfilm.  That's how I found material on 1993 bomb damage and repairs, but the place I went didn't have that much available for engineering topics.  Someday, I may go look somewhere else, once I get through the other WTC articles and other stuff I'm working on.  Of course, since you have expertise, maybe you can have better luck finding sources. --Aude (talk) 19:08, 10 July 2007 (UTC)
 * PS. there was some discussion on the peer review page.--Aude (talk) 19:08, 10 July 2007 (UTC)
 * Fair enough. Cheers. Basar 19:22, 10 July 2007 (UTC)

Here's a list of sources that I would look for.

It would definitely be worth the effort to get hold of these, but not sure when I'll get a chance to do so. If anyone else can find these or other sources, and add to the article, please do so. --Aude (talk) 19:27, 10 July 2007 (UTC)


 * Yes, I have found some of those sources on the website: Apparently you were correct to concentrate on the excavation methods as the foundation seems to be very un-interesting; I was expecting an elaborate deep foundation system. Apparently it is just a spread footing cast on rock. I looked for a natural place in the article to integrate that, but I am not sure where it should go. I did, however, add a sentence from one of those sources on why slurry walls were used instead of conventional methods. Basar 00:51, 11 July 2007 (UTC)


 * I suggest not linking to that site. Those articles might be okay, but the site is not exactly a reliable source.  Personally, I'd rather trek to the library and get these articles myself.  If you want to include those articles as refs, but without the link, that's okay and sometime in the next week or so, maybe I can go verify them. I don't know if the publisher would let me post copies of them somewhere, but maybe if I asked. --Aude (talk) 01:03, 11 July 2007 (UTC)

Room for improvement?
Not bad, but this needs a copy-edit and a peer review, I think. I found several sentences that read awkwardly and needed re-wording. So there's definitely an issue with the grammar and flow. Thoughts?— Wackymacs 08:55, 10 July 2007 (UTC)
 * It has had a peer review and is a Featured Article...see links to such actions in the tags at the top.--MONGO 09:44, 10 July 2007 (UTC)
 * I know it's a Featured Article. It doesn't mean it's "perfect" though - it also doesn't mean it shouldn't be improved. I can see plenty of places where a re-word and grammar work is needed. — Wackymacs 09:53, 10 July 2007 (UTC)
 * It's the encyclopedia that anyone can edit - get to it Wackymacs!!!! 81.156.127.109 09:55, 10 July 2007 (UTC)
 * Wackymacs...the first edit you did was fine. I had a little problem wiht the second, but the last three added some inaccuracies to the article. There was also one passage that read less easily after your change than before.--MONGO 10:42, 10 July 2007 (UTC)
 * I think it's a matter of personal opinion - and maybe an interest conflict. You obviously seem very protective of this article as you're very proud of it. Reverting back again. Discuss more. — Wackymacs 11:20, 10 July 2007 (UTC)
 * I fixed one mistake but the rest is valid and I see no problems. Please copy & paste into here what you're having problems with if anything. Thanks — Wackymacs 11:25, 10 July 2007 (UTC)

(reindent)I've reverted back to MONGO. Wackymacs has introduced grammatical error "Governor Robert B. Meyner objected the plan, resenting that" for "Objections to the plan came from New Jersey Governor Robert B. Meyner, who resented that" and purposeful ambiguity "with some of its upper floors used as a hotel" for possibly misleading clarity "with the upper floors used as a hotel." The other changes appear to be a matter of preferred word choice, rather than any dispute of fact, which is poor justification for the introduced problems. - BanyanTree 11:39, 10 July 2007 (UTC)
 * Unfortunately you reverted to the wrong version, since my first edit to this article was valid: "founded" sounds much better than "set up" (I changed a few other words and removed redundant commas). To be fair, this is a featured article and so it should represent the best writing quality on Wikipedia. Sorry about the other edits, I did rush them. — Wackymacs 12:13, 10 July 2007 (UTC)

Wire-walking guy
The French guy who walkedon the wire between the two towers did it while the WTC was still being built, I seem to remember. is this worth mentioning in the text? 81.156.127.109 09:58, 10 July 2007 (UTC)
 * If you can find a reference for it, sure. — Wackymacs 10:07, 10 July 2007 (UTC)
 * Not sure it has anything to do with the construction, unless it was in regards to the builders having the guy walk the tightrope for publicity purposes.--MONGO 10:38, 10 July 2007 (UTC)
 * yeah i remember seeing a pic and the tiles at the top of the tower aren't on yet hence not being built completely. i think there is an article on wikipedia about it. 121.127.192.166 10:59, 10 July 2007 (UTC)
 * Philippe Petit is the article, and he did it in 1974 so it's not relevant to the article. - BanyanTree 11:27, 10 July 2007 (UTC)
 * A mention of this guy (whose name escaped me) was the first thing I looked for in the article. He is definitely worth a "see also"; I'll add him as such. BrainyBabe 17:03, 10 July 2007 (UTC)
 * [[File:Bad Title Example.png]] as you can see the tower isn't done yet 203.129.63.34 04:52, 13 July 2007 (UTC)

Move page to "construction of the world trade center"
because right now the title is kind of ambiguous because it could be calling the towers buildings. 121.127.192.166 10:58, 10 July 2007 (UTC)

I was just about to post this. Do it now, it's ambiguous! --84.92.214.184 14:06, 10 July 2007 (UTC)

Yeah, because it's unclear whether this means the construction of the towers or the "building" itself, as in the noun. Make Wikipedia a better place. Macphisto12 14:24, 10 July 2007 (UTC)

Yes change the name to "Construction of the World Trade Center", it makes it much clearer. --Differentgravy 14:24, 10 July 2007 (UTC)

There needs to be a new survey 203.129.52.63 01:51, 11 July 2007 (UTC)

Requested move

 * The following discussion is an archived discussion of the . Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section. 

Building of the World Trade Center → World Trade Center (Construction) — logical to start article with name of center. Makes searching for all World Trade Center articles easier, eg the post 9/11 details are in "Word Trade Center Site" — bär lin er Talk 13:35, 10 July 2007 (UTC)


 * This is a subarticle of the main article - World Trade Center. It is linked there.  Not all subarticles start with "World Trade Center", such as Collapse of the World Trade Center, 7 World Trade Center, and the other buildings - 6 World Trade Center, 5 World Trade Center, 4 World Trade Center, Marriott World Trade Center, and the new buildings Freedom Tower, 150 Greenwich Street, etc.  We also have a navigation box that we can use to link articles together - WTC navigation.  Also, a poll isn't necessary.  A discussion will suffice. --Aude (talk) 13:50, 10 July 2007 (UTC)

"Building" is slightly ambiguous, "Construction" would be much clearer. --Differentgravy 14:26, 10 July 2007 (UTC)
 * But this article is about more than just the construction of...so the current title is more accurate...World Trade Center (Construction) is not acceptable.--MONGO 15:12, 10 July 2007 (UTC)

Survey

 * Feel free to state your position on the renaming proposal by beginning a new line in this section with  or  , then sign your comment with  . Since polling is not a substitute for discussion, please explain your reasons, taking into account Wikipedia's naming conventions.


 * Support Should definitely be re-named, "building" is rather ambiguous really. — Wackymacs 15:24, 10 July 2007 (UTC)
 * Oppose: although would support "construction of the World Trade Center". Reginmund 17:44, 10 July 2007 (UTC)
 * Support "Construction of the World Trade Center" - seems the obvious location - PocklingtonDan (talk) 20:14, 10 July 2007 (UTC)


 * Oppose I do not think the alternate wording accurately describes the breadth of material presented in the article. Basar 19:25, 10 July 2007 (UTC)
 * Oppose The proposed title makes it sound like World Trade Center is a Construction (since Californication is an album and Madonna is an entertainer). I would somewhat support moving to Construction of the World Trade Center.  The article is indeed about much more than just the construction, but I don't think the word building covers planning and designing it, and it introduces some ambiguity as to the subject of the article.  17Drew 21:03, 10 July 2007 (UTC)
 * Comment - there seems to be more support for a move to 'Construction of the World Trade Center' - I'd support that. --Merbabu 10:06, 15 July 2007 (UTC)
 * Comment. I'd support a move to 'Construction of the World Trade Center', which is a much better title than 'World Trade Center (Construction)', which seems to indicate an existing building rather than construction of a building. – Marco79 12:05, 15 July 2007 (UTC)

Discussion

 * Any additional comments:

The date of the beginning of construction (1969) must be wrong. Perhaps it refers to the construction of the towers after the site had been prepared. In 1961 I worked in Lower Manhattan (2 Lafayette St) not far from the site and my lunch hours were made hell by the construction workers sitting on sidewalks all around and commenting on any woman who passed by. Either in the two years there or at UC Berkeley 1963-65 I was taught about PERT charts and the example used was the World Trade Center construction - every beam was tracked from its fabrication to its delivery at the site. No truck to that site could enter Manhattan until another had left. I cannot cite a source for this beyond my own memories but doubtless it exists.216.151.21.130 18:00, 10 July 2007 (UTC)
 * In March 1965, the Port Authority began acquiring property and demolishing existing structures. Groundbreaking was on August 5, 1966, with site preparations taking place over many years. Actual construction of the North Tower began in August 1968 and the South Tower in 1969.  Though, when the Port Authority acquired PATH, they acquired the Hudson Terminal building, which was demolished at some point.  Maybe that's what you remember.  The Singer Building, once located where One Liberty Plaza is today, was also demolished.  The Washington Market was also demolished at some point in the years before the WTC was constructed.  Around 1960, One Chase Manhattan Plaza was constructed.  These were all very major projects that could make lunch hour hell.  Could it be one of these projects that you remember? --Aude (talk) 18:14, 10 July 2007 (UTC)


 * The above discussion is preserved as an archive of the . Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.

It was requested that this article be renamed but there was no consensus for it be moved. --Stemonitis 14:59, 16 July 2007 (UTC)

Masonic symbolism
Some claim the two towers represent Jachin and Boaz, used in Masonic symbolism with the Washington Square Arch. 

"All Masonic lodges have these two pillars at some location in their architecture. In the earliest Lodges, they were said to represent far more ancient pillars, supposedly erected by “the children of Lamech.” On those ancient pillars -- one of brick, one of stone -- were said to be engraved all the then known sciences to preserve them from destruction “by fire or inundation.” As such, they symbolized the esoteric importance of the knowledge of the builder's (mason’s) art, to be guarded and preserved by future faithful craftsmen. Simply put, according to Masonic legend, “the children of Lamech” were the inhabitants of Atlantis. This information, passed down from that prior highly advanced civilization, is supposed to form the basis of the Masonic secrets “from the ancient times."

"Shortly before the American Revolution, these original representations of “ancient, preserved knowledge” were replaced in Masonic lodges with two brass pillars, representing two similar pillars originally erected at the entrance to King Solomon's Temple in Jerusalem -- the Pillars of Jachin and Boaz. The new Masonic pillars took on the symbolic attributes of “establishment” and “strength,” cleverly concealing their continuing representation of the great catastrophe which had destroyed a previous epoch of “high civilization,” beneath additional layers of almost impenetrable (for most non-members) new symbolic interpretation."

Requested move-2
Building of the World Trade Center → Construction of the World Trade Center — From a previous requested move, it seems as if this would be supported more. It sounds the least ambiguous. —Reginmund 00:34, 10 August 2007 (UTC)

Survey

 * Feel free to state your position on the renaming proposal by beginning a new line in this section with  or  , then sign your comment with  . Since polling is not a substitute for discussion, please explain your reasons, taking into account Wikipedia's naming conventions.


 * Support: The current name sounds vague. The new name is much better. Chris! my talk 23:52, 11 August 2007 (UTC)
 * The request above noted that this is about "more than just the construction", which is why the article used to be at Design and construction of the World Trade Center. That makes more sense to me, and I would support it, but I don't think I can support the proposed title. Dekimasu よ! 03:13, 13 August 2007 (UTC)

It was requested that this article be renamed but there was no consensus for it be moved. --Stemonitis 09:10, 15 August 2007 (UTC)

Fair use rationale for File:East-side-wtc.png
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BetacommandBot 06:11, 27 October 2007 (UTC)

Steel description flawed
The reference 49 description of A36 steel erroneously ascribes it characteristics of varying yield strength from 36 to 100,000 PSI. This is incorrect - it has yield strength of at minimum 36 KSI (36,000 PSI) for plates and sections less than 1 inch thick and 32 KSI over 1 inch thick. Can someone who has better access to primary sources determine what steels were used in the outer column structures, so we can correct this? I could just fix this A36 comment, but there'd be an information gap left anyways. Thanks. Georgewilliamherbert (talk) 21:53, 30 January 2008 (UTC)

New section on anticipation of aircraft impact
I've added a section that we worked out over at the article on the collapse of the World Trade Center. It can probably be expanded but here's what we've got so far.--Thomas Basboll (talk) 13:59, 14 April 2008 (UTC)

Gravity load
In the lead and again in the body mention is made of the gravity load of the columns. Wording currently implies that the core shared a part of the load. The core actually supported 50% of the load while the perimeter columns supported 20%. It either needs rewording to make clear that the core carried most of the load or have the percentages included. Suggestions? Wayne (talk) 14:22, 22 April 2008 (UTC)


 * You are confusing ooad distribution with demand-to-capacity. Both the fire and perimeter carried 50% each, and under gravity load alone (no wind), the core was loaded to 50% of capacity whereas the perimeter was loaded to 20% capacity. Abdullah Ali 4z5 (talk) 13:56, 26 November 2023 (UTC)

Proposal to remove date-autoformatting
Dear fellow contributors

MOSNUM no longer encourages date autoformatting, having evolved over the past year or so from the mandatory to the optional after much discussion there and elsewhere of the disadvantages of the system. Related to this, MOSNUM prescribes rules for the raw formatting, irrespective of whether a date is autoformatted or not). MOSLINK and CONTEXT are consistent with this.

There are at least six disadvantages in using date-autoformatting, which I've capped here:

Removal has generally been met with positive responses by editors. Does anyone object if I remove it from the main text (using a script) in a few days’ time on a trial basis? The original input formatting would be seen by all WPians, not just the huge number of visitors; it would be plain, unobtrusive text, which would give greater prominence to the high-value links. Tony  (talk)  12:53, 23 July 2008 (UTC)


 * The suggested changes are okay with me. Please go ahead with the changes. --Aude (talk) 16:24, 23 July 2008 (UTC)

WHY?
Why is the World Trade Center still here? It's been demolished, and is gone forever, so thus it needs to be removed from Wikipedia, as it no longer exists. Please remove this article. Thank you.--75.0.33.123 (talk) 11:13, 4 September 2011 (UTC)

In response to your question, why is this article still here? Short answer is because these buildings once existed. People worked lived and played at this site, sadly also died at this site. In order to know what was once at this site the memory must be kept alive for future generations to better understand. — Preceding unsigned comment added by 73.195.64.86 (talk) 17:42, 9 July 2016 (UTC)

link to WTC main page
Hi, can you add in the header a link to the main article (World_Trade_Center)? Somehow I landed to Construction_of_the_World_Trade_Center, but from this article there is no easy direct link to the more general article about WTC... 116.6.52.162 (talk) 02:04, 6 November 2012 (UTC)

Lose Of Construction Documents And Records Pertaining to the Construction of The WTC by the Port Authority of NY & NJ on September 11th. 2001.
I have been working and nearing completion on a book about the former twin towers construction in the 1960's. In my research I was baffled by the fact that currently to date the Port Authority of NY & NY which build these great buildings has very little in the way of documents or articles even photographs pertaining to its construction. I was informed that The Port Authority of NY & NJ closed its library located in the North Tower of the former twin towers in 1995 and later subsequently lost what remained after the attacks of September 11th. 2001. Apparently their archives was also located within the Library. A few documents have surfaced over the years but not much in the way with loads of information. To date the Port Authority of NY & NJ only has approximately thirty photographs in different stages of construction. I have over three hundred unpublished photographic slides that will be part of my book showing excavation at the site to the slurry wall construction and then steel up to completion of the twin towers. Sadly I have made the decision to cut my book short for lack of information and years of fruitless research. Speaking on a more positive note, they say a picture is worth a thousand words and I can't wait to publish and show the world my now very rare and scares photographs of these beautiful buildings no longer existing while during their birth.

NIST also seems to have lost test results. The architect of the whole project was asked once about the possibility of a plane impact - "like a mosquito hitting a screen door". If he still is around, or his records, he might be able to back up his claim. Maybe NIST could redo its tests from data it had, and probably also lost. 2601:181:8301:4510:B99A:E75A:D1C4:7867 (talk) 02:23, 18 September 2016 (UTC)

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Regarding the ironworkers quoted in Gay Talese's book
I'm opening this discussion in regards to this text about ironworkers saying the Twin Towers were flimsy, which was recently deleted from this article and collapse of the WTC article. I will check the book in question later today to see the context of this quoted text. This may be a useful thing to include, but at the same time it's the opinion of a few workers, so that's why I'm opening this discussion. epicgenius (talk) 14:51, 28 August 2019 (UTC)
 * Its merely the comments of some guys used to working on heavier steel structures of an earlier period, particularly bridges that needed to support massive loads and span large distances between supports, so to their eyes, some of the steel of the towers seemed comparatively flimsy. This doesn't mean is was. However, the comments made by the engineer Hamburger could use further evaluation.--MONGO (talk) 15:26, 28 August 2019 (UTC)
 * Per my comments on epicgenius's talkpage, the open-web truss composite floor system was an unusual one that would have appeared flimsy to ironworkers who were used to heavy noncomposite WF-section (wideflange) framing systems. The system enjoyed brief popularity in the 1970s and 1980s, but has mostly been abandoned in favor of stiffer systems. Open-web joists or bar joists are nowadays mainly reserved for roof systems, where deflection margins are more generous, and floors usually employ composite decking with WF sections instead of trusses, which are perceived as less bouncy and are easier to fireproof. I don't think the observation is odd in that context, but it's anecdotal, hardly an authoritative engineering opinion. In any case, I'm curious about whether new text was added to the 2014 re-issue of the 1964 book. It sounds like something from a new introduction - if so, intros are usually broad reflections on context rather than authoritatively-sourced factual material. Acroterion   (talk)   16:56, 28 August 2019 (UTC)
 * Appears be an addendum titled "Afterward" in the earlier published book. All I can find with a google search easily where Hamburger stated the construction was "flimsy" was in a page posted by Stanford University a few months after the attacks. --MONGO (talk) 21:11, 28 August 2019 (UTC)
 * Yes, the cite in question is from the new chapter added in the 2014 edition. Talese follows up on the people (and their sons) he discusses in the 1964 book. Many of them worked on the WTC; three of the themes of the book, which the new chapter continues, is how ironworkers (*never* "steelworkers", as they point out to Talese) a) work on a variety of projects around the country and world, constantly moving to the next one (a bridge this year, a skyscraper next), b) get exposure to every aspect of the construction process through varying roles, and c) have their brothers, sons, and nephews (and, in the Mohawks' case, tribemembers) follow in the career. All three are relevant to the WTC discussion in the chapter.


 * The 1964 book itself is considered a classic in two ways: Beyond being a best-selling account of the Verrazano bridge's construction, it's an early example of New Journalism; Talese is one of the great practitioners of the genre, along with Tom Wolfe and Theodore White.


 * Hamburger is cited multiple times in both this article and Collapse of the World Trade Center. Ylee (talk) 01:26, 29 August 2019 (UTC)


 * Does Talese give any context for the ironworker's statement vis-a-vis my comments on the comparatively novel floor structure up the page?  Acroterion   (talk)   01:34, 29 August 2019 (UTC)


 * Not in such detail. Here is the full quote, with some more text:


 * "Hardly any of the Verrazano alumni took much pride in constructing the first Twin Towers, being appalled by the lightness of the floor beams they were directed to connect, the lack of interior support columns, the seeming fragility of the entire construction, and the hasty pace they were instructed to follow in adding to the skyline two tubular towers that suggested from afar a pair of elongated bird cages. "Flimsy" was how Iannielli had characterized the construction to me during one of our later meetings; and "flimsy" was also the word used by Ronald O. Hamburger, a member of a team of structural engineers assessing the performance of the World Trade Center during the terrorist attacks, the ensuing fires, and ultimately the demolition. "The floor trusses were relatively flimsy ... the trusses just fell apart." It was pointed out by other engineers that the buildings were about 90 percent "air," designed to achieve the utmost in rentable floor space and flexibility, unencumbered by columns, explaining why the rubble in the wake of the collapse was only a few stories high."


 * Talese next talks to an ironworker who worked on the new WTC, whose late father and grandfather worked on the Verrazano bridge and old WTC. In two paragraphs he says that he cannot speak on the old WTC, but discusses how the new tower's cement core and outside welded columns and beams makes the building very strong, and that the oldtimers who worked on both WTCs are very proud of the new one, implying in contrast to their feelings about the old. I can provide the full text of the two paragraphs if you'd like. Ylee (talk) 05:25, 29 August 2019 (UTC)
 * Modern skyscrapers all strive to maximize space so the mostly air issue would apply to virtually all late 1950s skyscrapers up to today. Secondly, heavier doesn't necessarily equate to greater structural stability. The WTC were built with modern designs of their times and were considered somewhat revolutionary for their time. While the opinions of ironworkers are fascinating they're not engineers and I find a few comments by one qualified engineer to be the only thing that might be worthy of inclusion. Even that sounds more like an off the cuff remark that never made it into the engineering record in the form of a peer reviewed paper.--MONGO (talk) 06:49, 29 August 2019 (UTC)
 * All buildings are about 90% air. After all, it's the air-filled parts that are useful to people. I think the main point is as I had expected - the trusses were not well regarded. For what it's worth from the point of view of Wikipedia (which is not much since it's my personal opinion/interpretation), the trusses were a bad idea, used to increase spans to eliminate interior columns. The nature of the trusses, along with their long spans, created unique structural reactions after the aircraft impacts and fires. I would like to see an engineering discussion of that design choice. Since about 1990 the building industry has found ways to obtain log-span columnless interior spaces by using regular steel with composite decks rather than composite truss structures. In New York State, all buildings containing trusses, wood or steel, must be placarded as such at the entrance for firefighter reference.
 * There has been an accumulation of events that have since been incorporated into structural engineering practice, in which designers are required to provide structural redundancy, minimizing single-point-of-failure collapse. The old style of skyscraper construction with short spans and heavy steel was naturally more redundant than core-and perimeter buildings like WTC 1 and 2. WTC 7 had its own single point of failure mode in a different way. This came to a head first in bridges, where several bridge failures changed how bridges are designed, and since the Murrah Building bombing in Oklahoma City and the WTC attacks, they have found their way into building design. I haven't run across a source that details all these design practice trends in one place.  Acroterion   (talk)   12:10, 29 August 2019 (UTC)

Steel strength
An editor just added a referenced note about the steel strength increasing with height. This was probably done to further reduce the mass of the upper parts of the structure, and because it would be too expensive to use a high grade for the heavy lower columns, but I might be committing OR to add that clarification. Can somebody find a citation for that informed analysis?  Acroterion   (talk)   13:34, 20 August 2022 (UTC)
 * I tried to find a citation for this but was not successful. In the process, I stumbled upon more than a hundred sources that may be useful, though they don't answer your specific question. These sources are listed under footnote 3 in . Unfortunately, I don't know if any of these sources confirm the facts that were recently added to this article. – Epicgenius (talk) 17:28, 22 August 2022 (UTC)

Number of workers who died building the WTC
Currently, the article states that 60 workers died during the construction of the World Trade Center, citing this PBS source. However, I have noticed a few potential issues:
 * The PBS source does not cite any sources for this figure; literally every other statistic on that webpage has a source, except for the number of workers who died.
 * I was unable to corroborate this figure in any other source. I previously consulted several books that discuss the construction of the WTC (specifically Gillespie (1999) and Glanz & Lipton (2003), but these books don't seem to cite the fact that 60 workers died.
 * This number seems extremely high, and I would have expected that a megaproject with that many deaths would have received extensive coverage. The WTC originally consisted of 6 buildings, including the low-rise structures; this would mean that, on average, 10 people died while constructing each building. By comparison, five workers died while constructing the Willis Tower, which was completed at roughly the same time. Even at the Empire State Building (which was completed four decades before the WTC, when safety standards were lower, and which was built within a matter of months), between 5 and 15 workers are estimated to have died. If sixty people did die while building the WTC, there probably was a reason for the death rate being that high, a reason that I have not been able to ascertain.

For these reasons, I would like to remove the claim that 60 workers died during the WTC's construction. Epicgenius (talk) 17:14, 7 April 2023 (UTC)
 * [Disclaimer: Brought this to Epicgenius' attention off-wiki.] My thinking here is either PBS typoed "6" or that for whatever reason they're using some very broad definition that includes deaths from natural causes in any company working on the project, although even there 60 would seem rather high. Either way, it's a tertiary source and is expected to reflect what's in the secondary sources, so if it doesn't, it isn't reliable (at least with respect to that claim). --  Tamzin  [ cetacean needed ] (she&#124;they&#124;xe) 21:28, 7 April 2023 (UTC)

Framed Tubes
The twin towers were not constructed using framed tubes. This is one reason why it failed. 69.112.10.127 (talk) 01:31, 8 September 2023 (UTC)
 * Source for your assertions?  Acroterion   (talk)   01:36, 8 September 2023 (UTC)

Steel panel weight
there is no way that panels with such widely varied plate thicknesses can have a constant weight of 22 tons. Abdullah Ali 4z5 (talk) 14:32, 26 November 2023 (UTC)
 * Please provide a reliable source for your claim that the thicknesses varied that widely. While it's true that panels of different sizes should have different weights, we're talking about a single size of panel measuring 10 by 36 feet across. The weight of panels of the same dimensions should be constant or else you'd have a quality control issue. – Epicgenius (talk) 02:41, 27 November 2023 (UTC)
 * It's literally in the preceding par
 * agra
 * "The perimeter structure was constructed of prefabricated modular pieces, which consisted of three columns, three stories tall, connected by spandrel plates. The perimeter columns had a square cross section, 14 inches (36 cm) on a side, and were constructed of welded steel plate. The thickness of the plates and grade of structural steel varied over the height of the tower, ranging from 36,000 to 100,000 pounds per square inch (260 to 670 MPa). The thickness of the steel plates decreased with height because they were required to support lesser amounts of building mass and wind loads on higher floors." Abdullah Ali 4z5 (talk) 05:44, 27 November 2023 (UTC)
 * You are right, my bad. I didn't notice that this article actually did say that the panel widths varied that widely, and that the sources cited say that, too. As for the 22-ton claim, this source actually says "up to 22 tons" (not uniformly 22 tons) and "either two or three stories high" (not two and a half stories high). I apologize for my confusion, and thanks for bringing this up. I have fixed this now. – Epicgenius (talk) 14:19, 27 November 2023 (UTC)