See other 9/11 Articles
Title: Why the towers fell: Two theories [by a civil engineer]
Source:
[None]
URL Source: http://www.vermontguardian.com/commentary/032007/TwinTowers.shtml
Published: Mar 1, 2007
Author: William Rice
Post Date: 2007-04-17 16:30:39 by honway
Ping List: *9-11* Subscribe to *9-11*
Keywords: None
Views: 13701
Comments: 196
Why the towers fell: Two theories By William Rice William Rice, P.E., is a registered professional civil engineer who worked on structural steel (and concrete) buildings in Boston, New York, and Philadelphia. He was also a professor at Vermont Technical College where he taught engineering materials, structures lab, and other building related courses, Posted March 1, 2007 Having worked on structural steel buildings as a civil engineer in the era when the Twin Towers were designed and constructed, I found some disturbing discrepancies and omissions concerning their collapse on 9/11. I was particularly interested in the two PBS documentaries that explained the prevailing theories as determined by two government agencies, FEMA and NIST (National Institute of Science and Technology). The first (2002) PBS documentary, Why the Towers Fell, discussed how the floor truss connectors failed and caused a “progressive pancake collapse.” The subsequent 2006 repackaged documentary Building on Ground Zero explained that the connectors held, but that the columns failed, which is also unlikely. Without mentioning the word “concrete,” the latter documentary compared the three-second collapse of the concrete Oklahoma City Murrah Federal Building with that of the Twin Towers that were of structural steel. The collapse of a concrete-framed building cannot be compared with that of a structural steel-framed building. Since neither documentary addressed many of the pertinent facts, I took the time to review available material, combine it with scientific and historic facts, and submit the following two theories for consideration. The prevailing theory The prevailing theory for the collapse of the 110-story, award-winning Twin Towers is that when jetliners flew into the 95th and 80th floors of the North and South Towers respectively, they severed several of each building’s columns and weakened other columns with the burning of jet fuel/kerosene (and office combustibles). However, unlike concrete buildings, structural steel buildings redistribute the stress when several columns are removed and the undamaged structural framework acts as a truss network to bridge over the missing columns. After the 1993 car bomb explosion destroyed columns in the North Tower, John Skilling, the head structural engineer for the Twin Towers, was asked about an airplane strike. He explained that the Twin Towers were originally designed to withstand the impact of a Boeing 707 (similar in size to the Boeing 767). He went on to say that there would be a horrendous fire from the jet fuel, but “the building structure would still be there.” The 10,000 gallons of jet fuel (half capacity) in each jetliner did cause horrendous fires over several floors, but it would not cause the steel members to melt or even lose sufficient strength to cause a collapse. This is because the short-duration jet fuel fires and office combustible fires cannot create (or transmit to the steel) temperatures hot enough. If a structural steel building could collapse because of fire, it would do so slowly as the various steel members gradually relinquished their structural strength. However, in the 100-year history of structural-steel framed buildings, there is no evidence of any structural steel framed building having collapsed because of fire. Let’s assume the unlikelihood that these fires could weaken all of the columns to the same degree of heat intensity and thus remove their structural strength equally over the entire floor, or floors, in order to cause the top 30-floor building segment (South Tower WTC #2) to drop vertically and evenly onto the supporting 79th floor. The 30 floors from above would then combine with the 79th floor and fall onto the next level down (78th floor) crushing its columns evenly and so on down into the seven levels below the street level. The interesting fact is that each of these 110-story Twin Towers fell upon itself in about ten seconds at nearly free-fall speed. This violates Newton’s Law of Conservation of Momentum that would require that as the stationary inertia of each floor is overcome by being hit, the mass (weight) increases and the free-fall speed decreases. Even if Newton’s Law is ignored, the prevailing theory would have us believe that each of the Twin Towers inexplicably collapsed upon itself crushing all 287 massive columns on each floor while maintaining a free-fall speed as if the 100,000, or more, tons of supporting structural-steel framework underneath didn’t exist. The politically unthinkable theory Controlled demolition is so politically unthinkable that the media not only demeans the messenger but also ridicules and “debunks” the message rather than provide investigative reporting. Curiously, it took 441 days for the president’s 9/11 Commission to start an “investigation” into a tragedy where more than 2,500 WTC lives were taken. The Commission’s investigation also didn’t include the possibility of controlled-demolition, nor did it include an investigation into the “unusual and unprecedented” manner in which WTC Building #7 collapsed. The media has basically kept the collapse of WTC Building #7 hidden from public view. However, instead of the Twin Towers, let’s consider this building now. Building #7 was a 47-story structural steel World Trade Center Building that also collapsed onto itself at free-fall speed on 9/11. This structural steel building was not hit by a jetliner, and collapsed seven hours after the Twin Towers collapsed and five hours after the firemen had been ordered to vacate the building and a collapse safety zone had been cordoned off. Both of the landmark buildings on either side received relatively little structural damage and both continue in use today. Contrary to the sudden collapse of the Twin Towers and Building #7, the four other smaller World Trade Center buildings #3, #4, #5, and #6, which were severely damaged and engulfed in flames on 9/11, still remained standing. There were no reports of multiple explosions. The buildings had no pools of molten metal (a byproduct of explosives) at the base of their elevator shafts. They created no huge caustic concrete/cement and asbestos dust clouds (only explosives will pulverize concrete into a fine dust cloud), and they propelled no heavy steel beams horizontally for three hundred feet or more. The collapse of WTC building #7, which housed the offices of the CIA, the Secret Service, and the Department of Defense, among others, was omitted from the government’s 9/11 Commission Report, and its collapse has yet to be investigated. Perhaps it is time for these and other unanswered questions surrounding 9/11 to be thoroughly investigated. Let’s start by contacting our congressional delegation. William Rice, P.E., is a registered professional civil engineer who worked on structural steel (and concrete) buildings in Boston, New York, and Philadelphia. He was also a professor at Vermont Technical College where he taught engineering materials, structures lab, and other building related courses.
Post Comment Private Reply Ignore Thread
Top • Page Up • Full Thread • Page Down • Bottom/Latest
Comments (1-22) not displayed.
.
.
.
#23. To: BeAChooser (#20)
Don't say anything about that McBeef guy either.
Bunch of internet bums ... grand jury --- opium den ! ~ byeltsin
[From BAC #18] http://www.nae.edu/nae/bridgecom.nsf/weblinks/CGOZ-58NLCB?OpenDocument "Reflections on the World Trade Center, Leslie E. Robertson, ... snip ... The lead structural engineer reflects on the rise and fall of the World Trade Center towers." [The same NAE source quoting Robertson] Yes, no doubt I could have made the towers braver, more stalwart. Indeed, the power to do so rested almost solely with me. Robertson was not even a partner in Skilling's firm. Robertson was an employee. The power to take an action, or to not take an action, rested with Skilling's firm. Should the partners of the firm have decided that something Robertson wanted to do would not be done, Robertson would have had three choices: (1) do as his employer wanted; (2) quit; (3) get fired. It is unrealistic for the employee to assert that the power to act rested almost solely with the employee. The power rests with the employer.
[BAC #18 quoting] ... no study of the impact of a 600-mile-an-hour plane ever existed. [BAC #20] The source for this is Paul Thompson’s Complete 9/11 Timeline. ROTFLOL! This is false. The calculation was done by Skilling (and only Skilling) and he was not one of the principle designers of the Towers. Nevertheless, and for the record, the towers did handle the impact of a 707 sized plane travelling almost that fast. http://wtc.nist.gov/media/Public%20Transcript%20021204%20Final1_withlinks.pdf Transcript of NIST Public Meeting in New York City – February 12, 2004 Table of Contents Jim Hill, National Institute of Standards and Technology ......... 1 Shyam Sunder, National Institute of Standards and Technology ..... 2 Public Comment Session I ........................................ 12 Sally Regenhard, Skyscraper Safety Campaign ..................... 12 Patricia Lancaster, New York City Department of Buildings ....... 15 Jim Tidwell, International Code Council ..........................17 Robert Solomon, National Fire Protection Association ............ 18 Jack Murphy, New York City Fire Safety Directors Association .... 19 Bill Bowen ...................................................... 21 James Quintiere, University of Maryland ......................... 23 Abolhassan Astaneh-Asl, University of California, Berkeley ...... 25 Lawrence Shapiro, W.R. Grace & Company .......................... 27 Tim Vellrath, Vellrath Engineering .............................. 29 * * * Dr. Sunder: Good morning. Jim has already introduced me as the lead investigator for the federal building and fire safety investigation of the World Trade Center disaster, and I will take this time this morning to explain to you our overall goals, our objectives, and where we are in terms of status and progress on the investigation. * * * I want to start first by talking about data collection because this is a very, very important aspect of what we're trying to do. We've collected a very large amount of data and information from a whole host of organizations: The building owners, the designers, the City of New York, both the fire department, the police department, and numerous other organizations that support this, including suppliers of materials, such as fireproofing. We have a few requests for materials that are lost, currently pending, or not yet located. We are making every effort to recreate that information, since much of it was lost when the buildings collapsed, especially those that deal with the buildings themselves. We, at this point, believe that we have received all of the essential information for us to do a credible investigation. And we have said that for the past three months, while we continue to work the problem of the few Page 5 Transcript of NIST Public Meeting in New York City - February 12, 2004 4 pieces of information that we still seek. And in doing so, we've received considerable cooperation from a whole host of organizations, including survivors and victim's families. I'm going to touch on a number of aspects of our investigation which I think it’s worth for the public to know at this point in time. First of all the issue with regard to the safety of the towers in an aircraft collision. Buildings are not designed to withstand the impacts of fuel laden commercial airliners. However, in the case of the World Trade Center, it was a consideration. The structural safety of the towers in an aircraft collision was considered in the original design. We have some documents from 1964 that suggest that. There's another document a month later that considers an aircraft impact at the 80th floor of one of the towers. When you put those two together, the events of September 11th look strikingly similar. The analysis that was reported from that time indicated that such collision would result in only local damage which could not cause collapse or substantial damage to the buildings. We now know that the buildings withstood the initial impact of the aircraft. The loss of life would have been far greater had the buildings collapsed upon impact. The large size of the buildings, the 208 x 208 feet floor plan area, and the dense exterior grid of columns, enabled the buildings to withstand the initial impact of the airplanes. But when you go beyond the initial impact to look at fire safety and life safety, we find that there are some contradictory views. There are two views on whether or not the effect of jet fuel and the subsequent - and the aircraft contents with regard to fire safety was considered or not. One view suggested that the fuel would dump into the building and there would be a horrendous fire. The second view suggested that possibly the fuel load and the fire damage may not have been considered. These are the opinions of people who should know what was done at that time. With regard to life safety, there are two views, again, on what would be the effect on occupant life safety. One view, which considered the fires, suggested that - one view which did not consider the fire suggested that the aircraft impact would not have endangered the lives and safety of occupants not in the immediate area of impact. Another view, which considered the fires, which took that into account, recognized that a lot of people would be killed, even though the building structure would still stand. We are still hopeful that we'll have further information available from wherever it resides, from the public, from people who know, to help us to better understand these different perspectives. And if we can get documents, that would be even better. * * *
[BAC #20] The source for this is Paul Thompson’s Complete 9/11 Timeline. ROTFLOL! This is false. The calculation was done by Skilling (and only Skilling) and he was not one of the principle designers of the Towers. Nevertheless, and for the record, the towers did handle the impact of a 707 sized plane travelling almost that fast. Until after the construction of the WTC was completed, Leslie Robertson had not yet risen to the level of junior partner in he engineering firm of John Skilling. Robertson was an employee, not a partner. Robertson eventually became a partner, but that did not happen until after construction was completed. A series of articles from Engineering News Record from 1964 to 1971, refer to either John Skilling or Leslie Robertson. I have boldfaced each name in each instance and have left no instance unquoted from the linked source. Robertson did not receive a mention until 1971. Prior to that there are repeated references to John Skilling, but nary a mention of Robertson. http://911research.wtc7.net/mirrors/guardian2/wtc/eng-news-record.htm SOME ARTICLES FROM ENGINEERING NEWS RECORD. ----- Architects are Minoru Yamasaki & Associates of Birmingham, Mich., and Emery Roth & Sons, of New York City. Structural engineers are Worthington, Skilling, Helle & Jackson, of Seattle. July 9, 1964 ----- The concept was explained to the New York Architectural League by John Skilling, a partner in Worthington, Skilling, Helle and Jackson, of Seattle, consulting structural engineers on the World Trade Center (see p. 124). April 2, 1964 ----- Walls resist wind. In designing the record-height towers against wind, Worthington, Skilling, Helle and Jackson adopted a scheme that does not rely on the core at all to take wind. Each tower will act as a vertical, cantilevered hollow tube. The giant Vierendeel trusses forming the loadbearing exterior walls will provide the required rigidity and strength to resist wind. All the horizontal shear will be resisted by the sides of the building parallel to the wind, and most of the overturning moment will be taken by the exterior walls normal to the wind. For economy in resisting the stresses, the wall columns will be made of high-strength steels, as indicated in the diagram above. April 2, 1964 ----- Minoru Yamasaki and Associates, Birmingham, Mich., and Emery Roth & Sons, New York City, are the Architects. Worthington, Skilling, Helle and Jackson, of Seattle, are, the consulting structural engineers; Jaros, Baum and Bowles, of New York City, the consulting mechanical engineers; and Joseph R. Loring and Associates, New York City, the consulting electrical' engineers. These firms were assisted in the design by the World Trade Center Planning Division under the direction of Malcolm P. Levy, and the PNYA engineering department, John M. Kyle,' chief engineer. January 23, 1964 ----- Fig . World Trade Center's towers will rise 1,350 ft in New York January 23, 1964 ----- To maintain uniform column and spandrel dimensions, structural engineers Worthington, Skilling, Helle & Jackson, of Seattle, specified a variety of steel strengths and sections to resist varying stresses throughout the frame. February 2, 1967 ----- Monti on management. Monti operates from the 10th floor of a building overlooking the WTC site. Although he concentrates most of his attention in areas where things go wrong, he maintains constant communication with the main contractors, with the architects and with the engineering consultants, Skilling, Helle, Christiansen, Robertson, Seattle, on structural design; Joseph Loring & Associates, New York City, on electrical work, and Jaros, Baum & Bolles, New York City, on mechanical. February 11, 1971 ----- ============== http://www.skyscrapersafety.org/html/article_11092001.html ----- In 1963, the firm entered a competition held by the Port Authority of New York and New Jersey to build in New York City what would be the tallest buildings ever constructed-the two towers of the World Trade Center. It was one of eight engineering firms-most of them large partnerships in New York-asked to submit proposals. Although the firm's tallest building up to that point was the twenty-story I. B.M. Building in Seattle, the architect of that building was Minoru Yamasaki-the same architect the Port Authority had selected for the World Trade Center. At a meeting to present the firm's proposal to the architect and developers, John Skilling, one of the four partners, used only a drawing pad, an easel, and some markers to make his pitch. ----- What Skilling proposed was a pure tube structure. His design was consistent with the general principles at work in the new generation of high-rises, but he carried the concept of the tube building farther than it had ever been taken before. (Or since: the Sears Tower, in Chicago, which replaced the World Trade towers as the world's tallest building in 1973, is also a tube building, but it is actually a cluster of nine smaller tubes.) The Twin Towers would be perforated steel boxes surrounding a hollow steel core. The outer box would be two hundred and eight feet on each side, and made of fourteen-inch-wide steel columns that were spaced on forty-inch centers-much closer than the fifteen-to-thirty-foot spaces that separate most supporting columns in a building. Like the cast-iron buildings of the previous century, the exterior walls would be load-bearing; unlike most skyscrapers, which hide their supporting columns, the Twin Towers would proudly wear their structure on their sleeves. Because there were so many load-bearing columns around the perimeter of each building, the engineers could completely eliminate all columns within the office space. Joining the outside tube to the inner core were state-of-the-art lightweight floor trusses that spanned sixty feet from core to exterior walls on two sides, and thirty-five feet on the other two sides. Yamasaki liked the design because it reminded him of a bamboo tube, an important totem for him. The Port Authority liked the design because, among other things, the towers would offer the single largest expanse of column-free office space in Manhattan-a realtor's dream. Skilling's firm got the commission, and Robertson, then thirty-five, moved to New York to open a new office, and to supervise the structural aspects of the building's construction. In 1983, the Seattle office and the New York office split, becoming two separate firms. Skilling (who died in 1998) and Robertson later argued about who was more responsible for the structure of the towers. "These are guys with big egos, and things got a little testy between them regarding who was ultimately responsible for the design," says Jon Magnusson, the chairman and C.E.O. of the Seattle-based firm, which is now called Skilling Ward Magnusson Barkshire. "Skilling said, 'It was me,' Robertson said, 'It was me,' but I think the truth is that both of them made a significant contribution." ----- http://911research.wtc7.net/wtc/analysis/design.html John Skilling John Skilling was the head structural engineer for the World Trade Center. In a 1993 interview, Skilling stated that the Towers were designed to withstand the impact and fires resulting from the collision of a large jetliner such as Boeing 707 or McDonald Douglas DC-8. Our analysis indicated the biggest problem would be the fact that all the fuel (from the airplane) would dump into the building. There would be a horrendous fire. A lot of people would be killed, ... The building structure would still be there. A white paper released on February 3, 1964 states that the Towers could have withstood impacts of jetliners travelling 600 mph -- a speed greater than the impact speed of either jetliner used on 9/11/01. The buildings have been investigated and found to be safe in an assumed collision with a large jet airliner (Boeing 707-DC 8) traveling at 600 miles per hour. Analysis indicates that such collision would result in only local damage which could not cause collapse or substantial damage to the building and would not endanger the lives and safety of occupants not in the immediate area of impact. ----- Frank Demartini's Statement Frank A. Demartini, on-site construction manager for the World Trade Center, spoke of the resilience of the towers in an interview recorded on January 25, 2001. The building was designed to have a fully loaded 707 crash into it. That was the largest plane at the time. I believe that the building probably could sustain multiple impacts of jetliners because this structure is like the mosquito netting on your screen door -- this intense grid -- and the jet plane is just a pencil puncturing that screen netting. It really does nothing to the screen netting. Demartini, who had an office on the 88th floor of the North Tower, has been missing since the 9/11/01 attack, having remained in the North Tower to assist in the evacuation. 6 Demartini had first worked at World Trade Center when Leslie E. Robertson Associates hired him to assess damage from the truck bombing in 1993. Like All Skyscrapers, the Twin Towers Were Over-Engineered One aspect of engineering that is not widely understood is that structures are over-engineered as a matter of standard practice. Steel structures like bridges and buildings are typically designed to withstand five times anticipated static loads and 3 times anticipated dynamic loads. The anticipated loads are the largest ones expected during the life of the structure, like the worst hurricane or earthquake occurring while the floors are packed with standing-room-only crowds. Given that September 11th was not a windy day, and that there were not throngs of people in the upper floors, the critical load ratio was probably well over 10, meaning that more than nine-tenths of the columns at the same level would have to fail before the weight of the top could have overcome the support capacity of the remaining columns. There is evidence that the Twin Towers were designed with an even greater measure of reserve strength than typical large buildings. According to the calculations of engineers who worked on the Towers' design, all the columns on one side of a Tower could be cut, as well as the two corners and some of the columns on each adjacent side, and the building would still be strong enough to withstand a 100-mile-per-hour wind. 7 Also, John Skilling is cited by the Engineering News Record for the claim that "live loads on these [perimeter] columns can be increased more than 2000% before failure occurs." ----- The WTC’s structural engineer, Skilling Helle Christiansen Robertson, called the member a floor truss on the drawings. "All sizes of all members of all trusses were provided in the drawings," says Robertson, currently LERA’s director of design. ============== Engineers blame collapses on fires Burning jet fuel's heat softened steel supports of WTC towers, they say; Sprinklers disabled, outmatched By Edward Gunts Sun Architecture Critic Originally published September 13, 2001 ... Worthington, Skilling, Helle and Jackson - the predecessor to Hooper's firm - was the structural engineer for the World Trade Center. Minoru Yamasaki was the lead architect. Engineers from the firm said eight years ago that the World Trade Center was designed to withstand the impact of a Boeing 707 crash, because they knew a smaller plane had crashed into the Empire State Building. But even then, they warned that it wouldn't be safe from a subsequent fire. "Our analysis indicated that the biggest problem would be the fact that all the fuel [from the jet] would dump into the building," lead structural engineer John Skilling told The Seattle Times in 1993. "There would be a horrendous fire. A lot of people would be killed. Skilling's scenario proved to be remarkably prescient. -----
[From BAC #18] http://www.nae.edu/nae/bridgecom.nsf/weblinks/CGOZ-58NLCB?OpenDocument "Reflections on the World Trade Center, Leslie E. Robertson, ... snip ... The lead structural engineer reflects on the rise and fall of the World Trade Center towers. ... snip ... It was assumed that the jetliner would be lost in the fog, seeking to land at JFK or at Newark. To the best of our knowledge, little was known about the effects of a fire from such an aircraft, and no designs were prepared for that circumstance. Indeed, at that time, no fireproofing systems were available to control the effects of such fires." What would a jetliner be doing trying to land in Manhattan??? It has no place to land in New York county, Richmond county, Kings county, or Bronx county. It would have to be seeking to land in Queens county on Long Island (JFK nee Idlewild, or LaGuardia), or over in Newark in New Jersey. The plane that hit the Empire State building got lost in the fog during WW2, and before all the jetliners had radar and could fly in the fog using instruments. There is not much chance of a jetliner getting lost and trying to land at Penn Station, Port Authority Bus Terminal, or on top of Madison Square Garden. Maybe there is a Bermuda Triangle formed by the train station, the bus station, and the garden. Even so, there is not much chance for a jetliner to get caught between Penn Station and MSG. It seems someone forgot about the invention of radar.
It is a White Paper from 1964. Groundbreaking occurred two years later in 1966. http://wtc.nist.gov/media/Public%20Transcript%20021204%20Final1_withlinks.pdf Transcript of NIST Public Meeting in New York City - February 12, 2004 Shyam Sunder, National Institute of Standards and Technology the lead investigator for the federal building and fire safety investigation of the World Trade Center disaster: We have some documents from 1964 that suggest that. The impact scenario that was considered is a Boeing 707 traveling at 600 miles an hour. There's another document a month later that considers an aircraft impact at the 80th floor of one of the towers. http://en.wikipedia.org/wiki/World_Trade_Center Construction Groundbreaking for the construction of the World Trade Center was on August 5, 1966. In 1970, construction was completed on One World Trade Center, with its first tenants moving into the building in December, 1970. Tenants first moved into Two World Trade Center in January 1972. http://en.wikipedia.org/wiki/White_paper A white paper is an authoritative report. White papers are used to educate customers, collect leads for a company or help people make decisions. They can also be a government report outlining policy.
I am not responsible to look for your Hormel samples on other threads or sites. The only things to be learned from researching your spam at other sites is to learn your Bozo count or why you were banned. It does seem that you have a fan club over at FU. http://www.freedomunderground.org/view.php?v=3&t=3&l=24&aid=23539#7 [Dakmar #7] ok, everyone wants BeAChooser to post here say Aye! [continental op #8] Absolutely. BRing him over I'll murder the bastard. ect,ect ect... [continental op #21] I always got time for bealooser. Drag the rat over here. I'll annihilate him.
Leslie Robertson was the coffee and donut boy for the real players, Skilling & Co. They sent him to NY to slop around in the mud, while in Seattle, they got the awards and had dinner. He is the only one alive from that time, I believe. He is jealous, vindictive that he never got the acclaim the others did. I think he eventually left to start his own company. Robertson now is only protecting what matters most, himself, money and his so called reputation.
Mark "I was real close to Building 7 when it fell down... That didn't sound like just a building falling down to me while I was running away from it. There's a lot of eyewitness testimony down there of hearing explosions. [..] and the whole time you're hearing "boom, boom, boom, boom, boom." I think I know an explosion when I hear it... — Former NYC Police Officer and 9/11 Rescue Worker Craig Bartmer
To be fair, Engineering News Record said, "Leslie E. Robertson, was the WTC's project manager." In the world of reality TV, on The Apprentice WTC, Skilling would have been Donald Trump and Robertson would have been the Project Manager.
I can't help that Sunder occasionally is unclear when he speaks. He said the towers collapsed in 9 and 11 seconds and that is demonstrably FALSE. What he meant is that the first pieces of material were observed to strike the ground 9 and 11 seconds after the collapse began. And the ONLY document they have does not say that the towers were DESIGNED for a 600 mph impact. It was a WHITE PAPER, not a design document, that only says the tower would survive a 600 mph impact. Which is not surprising, if it was DESIGNED to survive a 180 mph impact ... given the safety factors used by designers of buildings in those days and the dearth of tools with which they could model impacts in those days.
--------------------------------------------------------- Aren't you lucky. You get to receive one of the 15 posts I'm allowed each day.
Being a partner versus being the lead structural engineer on a project is more a matter of having the MONEY to become a partner, not whether one controls the detailed design of a given project. You are just throwing out a red herring, because I proved by posting numerous credible sources that state unequivocally that Robertson, not Skilling, was the lead structural engineer on the project and indeed one of the most influential members of the design team. It is a FACT that Robertson lived and worked in NYC which is where the design team was located. Skillings was still in Seattle and could not possibly have led the design team effectively. He may have conceptualize the design he wanted at the beginning, but it was Robertson and his team which made it a reality. And it would be Robertson, not Skilling, who would know the details of the design. Skilling was probably out marketing for new work for his company while his man worked the problem. That's what the CEOs of most firms do, by the way.
--------------------------------------------------------- Aren't you lucky. You get to receive one of the 15 posts I'm allowed each day.
http://en.wikipedia.org/wiki/Design_and_construction_of_the_World_Trade_Center "On September 20, 1962, the Port Authority announced the selection of Minoru Yamasaki as lead architect, and Emery Roth & Sons as associate architects.[26] Yamasaki came up with the idea of twin towers. To meet the Port Authority's requirement to build 10 million square feet of office space, the towers would each be 110-stories tall. Yamasaki remarked that the "obvious alternative, a group of several large buildings, would have looked like a housing project".[27] Yamasaki's design for the World Trade Center was unveiled to the public on January 18, 1964, with an eight-foot model.[27] So there is NO POSSIBLE WAY that any White Paper from 1964 affected the DESIGN. You don't know what you are talking about nolu_chan.
--------------------------------------------------------- Aren't you lucky. You get to receive one of the 15 posts I'm allowed each day.
The employee receives a salary. The partners in the company split the corporate profits. The partners decide what the corporate employees do or refrain from doing. If the employee does not like their decision he can quit or be fired. More BAC nonsense.
So there is NO POSSIBLE WAY that any White Paper from 1964 affected the DESIGN. Yamasaki was the architect. He did not do the engineering. The design of the building did not end with the display of an 8-foot model. But if you say so... After the design was BAC-complete, engineering concepts were explained to the New York Architectural League by the Big Boss Structural Engineer, John Skilling, a partner in Worthington, Skilling, Helle and Jackson. From Engineering News Record The concept was explained to the New York Architectural League by John Skilling, a partner in Worthington, Skilling, Helle and Jackson, of Seattle, consulting structural engineers on the World Trade Center (see p. 124). April 2, 1964
Right. Demolition of the buildings on the site did not even begin until 1966. Looking at all those old buildings is what enabled the engineers to do their work. ~rme~ Robertson was an employee of Skilling and company. The architect conceptualizes the design of the building. The building contractors and all those construction workers made it a reality. On March 25, 1966, four years after the enactment of the authorizing legislation, demolition finally began on 26 vacant buildings on the World Trade Center site.
And you think they wait to determine what the underlying major structure is until AFTER the Architect unveils the DESIGN to the public? ROTFLOL! Here are some signs from the same article that the design was well underway much earlier than 1964. "The exterior walls will comprise giant Vierendeel trusses, designed to act like huge cantilevered hollow tubes. They will be pre-assembled in units two stories high and about 10 ft wide, spliced at mid-height of the columns and midspan of the deep spandrel beams. The closely spaced columns will consist of 14-inch-sq hollow box sections, providing high torsional and bending resistance. ... snip ... July 9, 1964" Well clearly the design was well underway by July 1964. "Four New York City construction companies will independently review construction techniques planned for the two 110-story towers at the World Trade Center ... snip ... April 16, 1964" Gee, in April 1964 they are already awarding bids to construction folks to REVIEW construction techniques. So they must know what they were going to build. "The Port of New York Authority will. pay architects Minoru Yamasaki & Associates and Emery Roth & Sons an extra $800,000 over the initial $1.5-million fee for designing the World Trade Center in New York City. The new contract covers further design refinements for the superstructure of the twin 110-story towers, studies of integration of the PATH railroad station into the project. October 15, 1964" Hmmm ... in October 1964, they were already awarding more money for REFINEMENTS of the design. "HOW COLUMNS WILL BE DESIGNED FOR 110-STORY BUILDINGS ... snip ... April 2, 1964" Gosh, according to that article in April 1964 they already have all the major dimensions that we know about the structure ... the size of its members ... the response to loads ... the variations in steel strength over the height. So what did Skillling really do? "NEW YORK'S 110-STORY TOWERS ... Most local designers and builders want to know more about the New York World Trade Center and its sky-shattering heights (ENR Jan. 23, p. 33), but they generally like what they've seen so far. ... snip ... James Ruderman, consulting structural engineer "The structural design of the tower buildings shows a commendable job of rethinking, where ideas were given a lot of thought and not just treated routinely." ... snip ... January 30, 1964." Oh my gosh ... in January of 1964 a structural engineer is commenting on the structural design. He must have had something to comment on. Here's a real puzzler for you, NC. The White Paper written by Skilling that you are making such a big deal about was released February 3, 1964. So if the concept was just being explained to Skilling in APRIL of that year, how did he manage to do a detailed analysis to show that the structure could survive a 600 mph commercial jet impact back in February? Hmmmmmmm???? I anticipate that question will go just as unanswered as my question about what kept the molten steel molten 6 weeks after the collapse ... or my question about whether that photo of debris proves Steven Jones is a liar. ROTFLOL!
--------------------------------------------------------- Aren't you lucky. You get to receive one of the 15 posts I'm allowed each day.
No moron. You said at #34, "So there is NO POSSIBLE WAY that any White Paper from 1964 affected the DESIGN." A whole bunch of things could, and most certainly did, change in the design after 1964. What I said at #36 was, "The design of the building did not end with the display of an 8-foot model." In your idiocy, you asserted that prior to the White Paper in 1964, the design had been COMPLETED. Now in a bait and switch, in order to try to extract your sorry butt from your display of gross public dumb, you assert, "some signs from the same article that the design was well underway much earlier than 1964." Referring to the White Paper of February 3, 1964, you blathered at #18, "This was a back of the envelope calculation done AFTER the design was complete." That the design was UNDERWAY prior to 1964 would in no way support your prior claim that "there is NO POSSIBLE WAY that any White Paper from 1964 affected the DESIGN." Also, at #18, you did not say the design was UNDERWAY prior to the White Paper, you explicitly stated the White Paper was "done AFTER the design was complete." [BAC upper case emphasis.] AFTER 1964, Robertson's original engineering design plan had to be scrapped because tests in 1965 showed the buildings would sway beyond the limits of human tolerance. As Glanz and Lipton wrote in the New York Times, "Even today, Robertson has no trouble conjuring what two towers full of seasick office workers would have meant: 'A billion dollars right down the tube.' So he went back to work." The Height of Ambition: Part Four * * * Using exterior columns rather than interior ones for lateral stiffness not only increased the building's floor space; it also let Robertson reduce the total amount of structural steel in the building by at least 30 percent. The steel in the tightly spaced columns became as thin as a quarter-inch toward the top, where it had less load to carry. Robertson had succeeded in achieving his main goals for these exotic steel trees. But in designing what would become the feathery branches of those trees -- the floors -- he pushed even further toward lightweightness and cost savings. Rather than the massive beams or heavy framings that serve as horizontal floor supports in virtually every large steel office tower, Robertson chose bar-joist trusses -- airy, weblike networks of thin steel bars and angle irons topped with corrugated decking. Those trusses, which spanned as much as 60 feet, had two critical roles: they held up the concrete floors, and they provided lateral support to the exterior columns, keeping them from buckling under the load they carried. According to Robertson's figures, the trusses worked as well as heavy traditional girders and beams in performing those roles under ordinary circumstances. What he did not take into account was the extraordinary conditions of an intense, violent fire. Girders and beams would be far superior under those circumstances. Thin steel elements heat up and soften faster than thick ones. But in recent conversations, Robertson has said that architects generally handle anything dealing with fire in building projects, not engineers, so he did not think about this reduction in safety. Robertson and the Port Authority made another choice that proved fateful decades later. They chose not to use thick masonry or cement to encase the three escape stairways in each tower but rather light sheets of gypsum. Although the gypsum was extremely resistant to fire, and less likely than masonry to crack when the building swayed in the wind, it would work only if it remained intact -- and it was much more susceptible to being shaken loose or damaged by an explosion or any other kind of unexpected impact. There was another factor that Robertson had to take into account: the swaying motion of his buildings. The lightweight steel skeletons would not only put people unnaturally high in the air, as all skyscrapers do. They would let the buildings sway back and forth in the wind, like the biggest, leafiest trees ever planted. Heavy masonry-clad high-rises like the Empire State Building had never had to deal with this problem. For that reason, engineers had never measured how much swaying motion humans could stand before they became dizzy, seasick, frightened or disoriented. To answer that question, Robertson turned to an expert in human perception in Eugene, Ore. -- a spot as far removed from the New York press as he could find. Paul Hoffman, a psychologist, agreed to perform a secret series of experiments to find out just how much swaying motion was too much. Hoffman purchased a small office building in downtown Eugene and in the summer of 1965 put an ad in the local paper offering free eye checkups at a ''vision research center.'' But it was actually an elaborate ruse: the optometrist who conducted the eye exams was one of Hoffman's employees, Paul R. Eskildsen. And as each patient stared at triangles projected on the wall, a hidden technician would trigger a giant set of hydraulics underneath the room that heaved it back and forth like a big saltshaker. ''This is a strange room,'' one patient said, according to Eskildsen's detailed notes. ''I suppose it's because I don't have my glasses on. Is it rigged or something? It really feels funny.'' Patient after patient reacted the same way -- becoming dizzy and confused soon after the eye exam began. Humans, Hoffman discovered, were much more sensitive to motion than anyone had realized. A few inches of sway over 5 or 10 seconds set off psychophysical alarm bells. ''The people who were most surprised of all were the engineering firm and the Port Authority,'' Hoffman says. First, Port Authority officials trooped out to Eugene. Old photos show them milling around the little optometrist's office, looking flummoxed. Then they insisted on redoing the experiments by swinging a makeshift office on cables inside one of the Lincoln Tunnel's ventilation towers on Manhattan's West Side. ''It was a big packing crate, is what it was, that they had dolled up to look like an office,'' says Eskildsen, who traveled to New York for the new round. ''I had two guys outside who pushed the room. It was hilarious.'' About 40 Port Authority officials rode in the contraption. The results were the same. Wind-tunnel experiments in Fort Collins, Colo., confirmed that Robertson's initial design would sway far beyond those human tolerances, says Jack Cermak, then a professor of civil engineering and the director of the wind-tunnel laboratory at Colorado State University. Even today, Robertson has no trouble conjuring what two towers full of seasick office workers would have meant: ''A billion dollars right down the tube.'' So he went back to work. * * * But Robertson still had one more set of structural calculations to perform. Lawrence Wien, who was continuing his fight against the towers, had begun to remind New Yorkers publicly of a Saturday morning in July 1945, when a B-25 bomber, lost in the fog, barreled into the 79th floor of the Empire State Building. Most of the 14 people who died were incinerated by a fireball created when the plane's fuel ignited, even though the fire was quickly contained. The following year, another plane crashed into the 72-story skyscraper at 40 Wall Street, and yet another one narrowly missed the Empire State Building, terrifying sightseers on the observation deck. Wien and his committee charged that the twin towers, with their broader and higher tops, would represent an even greater risk of midair collision. They ran a nearly full-page ad in The Times with an artist's rendition of a commercial airliner about to ram one of the towers. ''Unfortunately, we rarely recognize how serious these problems are until it's too late to do anything,'' the caption said. The Port Authority was already trying to line up the thousands of tenants it would need to fill the acres of office space in the towers. Such a frightful vision could not be left unchallenged. Robertson says that he never saw the ad and was ignorant of the political battle behind it. Still, he recalls that he addressed the question of an airplane collision, if only to satisfy his engineer's curiosity. For whatever reason, Robertson took the time to calculate how well his towers would handle the impact from a Boeing 707, the largest jetliner in service at the time. He says that his calculations assumed a plane lost in a fog while searching for an airport at relatively low speed, like the B-25 bomber. He concluded that the towers would remain standing despite the force of the impact and the hole it would punch out. The new technologies he had installed after the motion experiments and wind-tunnel work had created a structure more than strong enough to withstand such a blow. Exactly how Robertson performed these calculations is apparently lost -- he says he cannot find a copy of the report. Several engineers who worked with him at the time, including the director of his computer department, say they have no recollection of ever seeing the study. But the Port Authority, eager to mount a counterattack against Wien, seized on the results -- and may in fact have exaggerated them. One architect working for the Port Authority issued a statement to the press, covered in a prominent article in The Times, explaining that Robertson's study proved that the towers could withstand the impact of a jetliner moving at 600 miles an hour. That was perhaps three times the speed that Robertson had considered. If Robertson saw the article in the paper, he never spoke up about the discrepancy. No one else issued a correction, and the question was answered in many people's minds: the towers were as safe as could be expected, even in the most cataclysmic of circumstances. There were only two problems. The first, of course, was that no study of the impact of a 600-mile-an-hour plane ever existed. ''That's got nothing to do with the reality of what we did,'' Robertson snapped when shown the Port Authority architect's statement more than three decades later. The second problem was that no one thought to take into account the fires that would inevitably break out when the jetliner's fuel exploded, exactly as the B-25's had. And if Wien was the trade center's Cassandra, fire protection would become its Achilles' heel. * * * [nc - there are at least a few more problems. Robertson's assertion of being unaware of the Wein ad and the political battle is not credible. Perhaps Robertson performed only an imaginary study consisting of nothing more than some propaganda released to the press, or he blew smoke at the architect. A prominent article in the New York Times explained that Robertson's study proved that the towers could withstand the impact of a jetliner moving at 600 miles an hour. There can be no credible assertion of unawareness by all concerned in the building of the WTC and no correction was issued. Robertson's three decades late assertion that he considered only a plane going 180 mph is not credible.] Compare with BAC drivel at #18
I have concluded that the only purpose BAC has here is to derail all 9-11 discussions with spam filled posts and outrageous claims. He's the Donald Segretti showing up to sabotage an open forum and make it his agenda. I put him on Bozo, but his impact on these threads is still seen, as he sucks out the oxygen from the conversation. I tend to skip any thread in which he participates actively, and I suspect that is one of his objectives, since disruption is his primary goal.
Yes, diversion/disruption appears to be his main objective. One way to counter it is to know when to quit replying to his replies. When you have made a point that effectively answers all his previous objections, that is the time to quit. The entire thread is there for people to absorb, if they take the time, and if the "knock-out" reply is enough, the thoughtful people will see it. Even if the readers don't "get it" in real-time, they can go back through the archives and see for themselves who was right and who was wrong. Sure, he will crow a NON SEQUITUR that he "won" if he gets in the last word. In the case of the invasion and occupation of Iraq, everyone knows now that he was wrong about everything. You have to be patient, but the truth will out.
Another aspect people overlook is all the mechanical floors were not the truss design but conventual heavy girder contruction to support the mechanicals of each 1/3 of the towers.
Mark "I was real close to Building 7 when it fell down... That didn't sound like just a building falling down to me while I was running away from it. There's a lot of eyewitness testimony down there of hearing explosions. [..] and the whole time you're hearing "boom, boom, boom, boom, boom." I think I know an explosion when I hear it... — Former NYC Police Officer and 9/11 Rescue Worker Craig Bartmer
It doesn't matter what one posts to "IT". Wether you provide links, pictures or paragraphs. Thats why I have never provided any links to "IT". Why feed "IT" any info that "IT" could split hairs with.
Mark "I was real close to Building 7 when it fell down... That didn't sound like just a building falling down to me while I was running away from it. There's a lot of eyewitness testimony down there of hearing explosions. [..] and the whole time you're hearing "boom, boom, boom, boom, boom." I think I know an explosion when I hear it... — Former NYC Police Officer and 9/11 Rescue Worker Craig Bartmer
You're right. There's no shortage of examples. And it doesn't matter if someone has real life experience in matters pertinent to the tower collapse incident, he/she/it will try to discredit them. In that attempt, there may be a link included to prove his/her/its point, and in quoting from that link only the "convenient" information is told; but when an important part of the information from that link is brought out that he/she/it didn't mention, it results in more ridicule. Moreover, he/she/it also adamantly and openly refuses to answer ANY other glaring pertinent inconsistencies and/or questions concerning 9/11 You're not the only one. But like you said, it's to little avail...
No matter how noble the objectives of a government; if it blurs decency and kindness, cheapens human life, and breeds ill will and suspicion - it is an EVIL government. Eric Hoffer
The design of the major structural elements of the towers surely had to have been completed by February 1964. Otherwise, Skilling could not possibly have completed an analysis of the structure's ability to survive a high speed plane crash that he published a White Paper about on February 3, 1964. You can't have it both ways NC. Either the White Paper is simply nonsense based on an incomplete design or the design (as far as what would be necessary to determine the resistance of the towers to plane impact) was completed by February 3, 1964. And since it must have taken some time to do the analysis that is claimed and write the White Paper, that would imply the design was essentially finished before January 1964. But he didn't change the essential structure during that revision. The revision must have consisted of very few changes because the articles you linked and quoted from 1964 and earlier show design details (size of columns, spacing, steel strengths, etc) that agree quite well with the final design. And indeed, the article you quote doesn't say the revision involved changes in the major structure. Your article is telling us that contrary to what the CT community has been saying, the WTC tower design was MORE vulnerable to fire than other steel skyscrapers (which usually uses girders and beams)? Well ... perhaps that explains why they were the first skyscrapers to collapse due to fire. Oh my goodness ... yet another difference between the WTC tower design and most other skyscraper designs. One that again makes the towers MORE vulnerable to fire if a plane crash has occurred. Are you finally admitting that it was Robertson's design ... not Skilling's. Good for you. Again, what YOU posted says Robertson did look at the tower's performance for a low speed plane lost in fog, not a high speed impact. And one more point ... this points out that Robertson, like Skilling, did an analysis AFTER the design was done. Crash of planes into the towers was apparently not a DESIGN LOAD so it is incorrect to claim that the towers were DESIGNED for even this plane crash. It's just fortuitous for them that calculations showed the towers would survive a plane impact. Otherwise, they might have had to redesign the whole tower. Right? New technologies? That doesn't sound like he just added thickness to steel members or increased the steel strengths, does it? Let's see ... what could they be talking about? Maybe the outrigger space frame which linked the outside wall to the services core? No ... that was part of the initial concept. Wait! I know what they are talking about. http://www.nae.edu/nae/bridgecom.nsf/weblinks/CGOZ-58NLCB "A viscoelastic damping system was invented and patented to ameliorate the wind-induced dynamic component of building motion by dissipating much of the energy of that motion . . . acting more or less like shock absorbers in an automobile. With these dampers, we could control the swaying motion without having to use large quantities of structural steel. This was the first time engineered dampers were used to resist the wind-induced swaying motion of a building." Now my question to you is this. Do you think those viscoelastic dampers significantly affected the resistance of the towers to plane impact? Or increased it's fire resistance? Or affected the way the tower would collapse once fire did its thing? No? Then I don't know why you even bring this up in this debate other than muddy the waters and keep folks from seeing the essential issues. Fine. If you want to claim that no study of the tower's resistance to aircraft impact was performed, that's ok with me. Because I thought it is the CT community that insists the towers were DESIGNED to survive multiple high speed plane crashes. What are you going to do, NC ... just ignore the real mystery here? The link YOU PROVIDED tells us that the concept for the towers was just explained to Skilling in April of 2004. Yet he published his White Paper (where you claim he did a design analysis of the towers) in February 3, 1964. Impossible? Yes.
--------------------------------------------------------- Aren't you lucky. You get to receive one of the 15 posts I'm allowed each day.
Exactly where have I diverted the discussion, roughrider? The subject of this thread is why the towers fell. ALL my posts have concerned that subject in one way or another. You just don't like the fact that I showed that you and the others here really don't understand the issues, science, engineering, facts or even logic. Then you should have quit back on post #1 when I took the subject article of this thread apart and brought into real doubt the qualifications of its supposed author. Tell you what, roughrider, since you insist we stay on topic. Why don't you respond to my criticisms of the article in post #1. You can start by providing proof that Rice is who he says he is. Show us his resume. Tell us where he got his degree. Who did he work for while working in the field? Show me anything from Vermont Technical College that actually proves he worked or works there. I'm curious, roughrider. Since you are such a master of logic, can you explain how Skillings could have done a definitive analysis of the towers resistance to plane impact that he published in February 1964 if the design wasn't done by then? For that matter, does the claim that the concept of the design was first explained to Skilling in April 1964 make any sense if he published a White Paper analysis of the towers resistance to aircraft impact in February 1964? Or is it time for you to quit? ROTFLOL!
--------------------------------------------------------- Aren't you lucky. You get to receive one of the 15 posts I'm allowed each day.
No, Kamala, here's why you never provide links to what you claim. http://www.fire.nist.gov/fds/docs/fds_tech_guide_4.pdf In the acknowledgments section it states "The Fire Dynamics Simulator has been under development for almost 25 years." In Chapter 2 it states that "Version 1 of FDS was publicly released in February 2000". Gee ... that was before the WTC project, wasn't it. ROTFLOL! And that's just the latest of MANY examples.
--------------------------------------------------------- Aren't you lucky. You get to receive one of the 15 posts I'm allowed each day.
Says the guy who claimed real life experience with regards to structures and then said "EVERYTHING is stronger in compression than in tension" when talking about steel structural elements. Which is completely false. ROTFLOL! You will not find the truth about 9/11 if you start from a foundation of misinformation and lies. You will only end up discrediting the attempt to get that truth.
--------------------------------------------------------- Aren't you lucky. You get to receive one of the 15 posts I'm allowed each day.
Actually, it was the architects and engineers, per a white paper and an unchallenged article in the New York Times, by which questions about the safety of the soon to be built WTC were addressed to assuage the public. They claimed that the building would withstand a hit by a Boeing 707 at 600 mph. Maybe they lied, or maybe they actually designed the WTC to sustain a hit by the largest jetliner then in the sky going at 600 mph. It is only repeating what was said contemporaneously and publicly. Either they did it or they lied about doing it.
[BAC #46 to roughrider] Exactly where have I diverted the discussion, roughrider? BAC constantly invents "facts" or distorts facts and attributes statements or arguments to the other party which were not made, and he can proceed to argue against a flawed argument of his own manufacture, making believe he is arguing against something said by the other party. Let me explain how bareback rider changes and diverts the conversation with a big lie. This is just typical BAC. [BAC at #45 to nolu_chan] "The link YOU PROVIDED tells us that the concept for the towers was just explained to Skilling in April of 2004. (sic -1964) Yet he published his White Paper (where you claim he did a design analysis of the towers) in February 3, 1964. [BAC at #46 to roughrider] "For that matter, does the claim that the concept of the design was first explained to Skilling in April 1964 make any sense if he published a White Paper analysis of the towers resistance to aircraft impact in February 1964?" Here we have another BAC BIG LIE. NO SOURCE ever asserted that "the concept of the design was first explained to Skilling in April 1964." In my #26, I quoted an article demonstrating that Skilling presented his design in 1963: ----- What Skilling proposed was a pure tube structure. His design was consistent with the general principles at work in the new generation of high-rises, but he carried the concept of the tube building farther than it had ever been taken before." This is just the way BAC operates. The concept was explained to the public in January 1964 and according to BAC it was first explained to the chief structural engineer in April 1964 - only in BAC world.
And it did. At least close to a 600 mph impact by a comparably sized plane. Nope. They didn't. We have proof. The towers survived the impact. Nope. They did not. The lead structural engineer states that the structure was designed for a 180 mph impact. The ANALYSIS that was done to see it might survive a 600 mph impact was done AFTER the design of the major structural elements. I think I proved that. You tried to pull a fast one here, NC, AND YOU GOT CAUGHT.
--------------------------------------------------------- Aren't you lucky. You get to receive one of the 15 posts I'm allowed each day.
You never answered my post. Well?
The buildings have been investigated and found to be safe in an assumed collision with a large jet airliner (Boeing 707—DC 8) traveling at 600 miles per hour. Analysis indicates that such collision would result in only local damage which could not cause collapse or substantial damage to the building and would not endanger the lives and safety of occupants not in the immediate area of impact. 4 http://911research.w >http://tc7.net/wtc/analysis/d esign.html
#24. To: BeAChooser (#18)
#25. To: BeAChooser, Kamala, honway (#20)
#26. To: BeAChooser, Kamala, honway (#20)
Fig . Proposed skyscrapers will dominate the skyline of downtown Manhattan.
Fig . Floorbeams will span from exterior columns to elevator-core walls.
Fig . Structural consultant John Skilling.
Fig . Architects Richard (left) and Julian Roth and Minoru Yamasaki.
#27. To: BeAChooser (#18)
#28. To: BeAChooser (#18)
This was a back of the envelope calculation done AFTER the design was complete.
Buildings are not designed to withstand the impacts of fuel laden commercial airliners. However, in the case of the World Trade Center, it was a consideration. The structural safety of the towers in an aircraft collision was considered in the original design.
#29. To: BeAChooser (#18)
I've provided links to back my assertion up over and over in previous threads here at 4um (not to mention uncounted times at LP). If you weren't paying attention, NC, that's your problem.
#30. To: nolu_chan (#28)
#31. To: Kamala, BeAChooser (#30)
Leslie Robertson was the coffee and donut boy for the real players, Skilling & Co. They sent him to NY to slop around in the mud, while in Seattle, they got the awards and had dinner.
#32. To: nolu_chan, ALL (#25)
Buildings are not designed to withstand the impacts of fuel laden commercial airliners. However, in the case of the World Trade Center, it was a consideration. The structural safety of the towers in an aircraft collision was considered in the original design. We have some documents from 1964 that suggest that. The impact scenario that was considered is a Boeing 707 traveling at 600 miles an hour.
#33. To: nolu_chan, ALL (#26)
Until after the construction of the WTC was completed, Leslie Robertson had not yet risen to the level of junior partner in he engineering firm of John Skilling. Robertson was an employee, not a partner. Robertson eventually became a partner, but that did not happen until after construction was completed.
#34. To: nolu_chan, ALL (#28)
"This was a back of the envelope calculation done AFTER the design was complete."
It is a White Paper from 1964. Groundbreaking occurred two years later in 1966.
#35. To: BeAChooser (#33)
Being a partner versus being the lead structural engineer on a project is more a matter of having the MONEY to become a partner, not whether one controls the detailed design of a given project.
#36. To: BeAChooser (#34)
Yamasaki's design for the World Trade Center was unveiled to the public on January 18, 1964, with an eight-foot model.[27]
http://911research.wtc7.net/mirrors/guardian2/wtc/eng-news-record.htm
#37. To: BeAChooser (#33)
It is a FACT that Robertson lived and worked in NYC which is where the design team was located. Skillings was still in Seattle and could not possibly have led the design team effectively. He may have conceptualize the design he wanted at the beginning, but it was Robertson and his team which made it a reality.
http://www.greatbuildings.com/buildings/World_Trade_Center_History.html
#38. To: nolu_chan, ALL (#36)
"Yamasaki's design for the World Trade Center was unveiled to the public on January 18, 1964, with an eight-foot model.[27]"
[BAC] - So there is NO POSSIBLE WAY that any White Paper from 1964 affected the DESIGN.
Yamasaki was the architect. He did not do the engineering.
The design of the building did not end with the display of an 8-foot model.
The concept was explained to the New York Architectural League by John Skilling, a partner in Worthington, Skilling, Helle and Jackson, of Seattle, consulting structural engineers on the World Trade Center (see p. 124).
April 2, 1964
#39. To: BeAChooser (#38)
http://tinyurl.com/2vm8fu
The New York Times, Sunday Edition
September 8, 2002
The Height of Ambition: Part Four
By JAMES GLANZ and ERIC LIPTON
#40. To: all (#0)
(Edited)
#41. To: Paul Revere (#40)
#42. To: nolu_chan (#39)
#43. To: roughrider (#41)
#44. To: Paul Revere (#40)
I have concluded that the only purpose BAC has here is to derail all 9-11 discussions with spam filled posts and outrageous claims. He's the Donald Segretti showing up to sabotage an open forum and make it his agenda.
I put him on Bozo
#45. To: nolu_chan, ALL (#39)
In your idiocy, you asserted that prior to the White Paper in 1964, the design had been COMPLETED.
Referring to the White Paper of February 3, 1964, you blathered at #18, "This was a back of the envelope calculation done AFTER the design was complete."
AFTER 1964, Robertson's original engineering design plan had to be scrapped because tests in 1965 showed the buildings would sway beyond the limits of human tolerance. As Glanz and Lipton wrote in the New York Times, "Even today, Robertson has no trouble conjuring what two towers full of seasick office workers would have meant: 'A billion dollars right down the tube.' So he went back to work."
What he did not take into account was the extraordinary conditions of an intense, violent fire. Girders and beams would be far superior under those circumstances. Thin steel elements heat up and soften faster than thick ones.
They chose not to use thick masonry or cement to encase the three escape stairways in each tower but rather light sheets of gypsum. Although the gypsum was extremely resistant to fire, and less likely than masonry to crack when the building swayed in the wind, it would work only if it remained intact -- and it was much more susceptible to being shaken loose or damaged by an explosion or any other kind of unexpected impact.
Wind-tunnel experiments in Fort Collins, Colo., confirmed that Robertson's initial design would sway far beyond those human tolerances,
Still, he recalls that he addressed the question of an airplane collision, if only to satisfy his engineer's curiosity. For whatever reason, Robertson took the time to calculate how well his towers would handle the impact from a Boeing 707, the largest jetliner in service at the time. He says that his calculations assumed a plane lost in a fog while searching for an airport at relatively low speed, like the B-25 bomber. He concluded that the towers would remain standing despite the force of the impact and the hole it would punch out.
The new technologies he had installed after the motion experiments and wind-tunnel work had created a structure more than strong enough to withstand such a blow.
Robertson's assertion of being unaware of the Wein ad and the political battle is not credible. Perhaps Robertson performed only an imaginary study consisting of nothing more than some propaganda released to the press, or he blew smoke at the architect.
#46. To: roughrider, Paul Revere, nolu_chan, ALL (#41)
Yes, diversion/disruption appears to be his main objective.
One way to counter it is to know when to quit replying to his replies.
When you have made a point that effectively answers all his previous objections, that is the time to quit.
#47. To: Kamala, roughrider, ALL (#43)
Kamala to roughrider - It doesn't matter what one posts to "IT". Wether you provide links, pictures or paragraphs. Thats why I have never provided any links to "IT". Why feed "IT" any info that "IT" could split hairs with.
[Kamala] - The FDS software was so full of bugs it was a joke. None of this computer software was tested or existed before the WTC research project.
#48. To: innieway, Paul Revere, ALL (#44)
And it doesn't matter if someone has real life experience in matters pertinent to the tower collapse incident, he/she/it will try to discredit them.
Moreover, he/she/it also adamantly and openly refuses to answer ANY other glaring pertinent inconsistencies and/or questions concerning 9/11
#49. To: BeAChooser (#45)
If you want to claim that no study of the tower's resistance to aircraft impact was performed, that's ok with me. Because I thought it is the CT community that insists the towers were DESIGNED to survive multiple high speed plane crashes.
#50. To: BeAChooser, roughrider, Paul Revere, ALL (#46)
"In 1963, the firm entered a competition held by the Port Authority of New York and New Jersey to build in New York City what would be the tallest buildings ever constructed-the two towers of the World Trade Center. It was one of eight engineering firms-most of them large partnerships in New York-asked to submit proposals. Although the firm's tallest building up to that point was the twenty-story I. B.M. Building in Seattle, the architect of that building was Minoru Yamasaki-the same architect the Port Authority had selected for the World Trade Center. At a meeting to present the firm's proposal to the architect and developers, John Skilling, one of the four partners, used only a drawing pad, an easel, and some markers to make his pitch.
At #34, BAC quoted Wikipedia stating Yamasaki presented his design to the public in January 1964: "Yamasaki's design for the World Trade Center was unveiled to the public on January 18, 1964, with an eight-foot model."
In my #36, I quoted an April 2, 1964 article which documented an explanation of the concept BY John Skilling: "The concept was explained to the New York Architectural League by John Skilling, a partner in Worthington, Skilling, Helle and Jackson, of Seattle, consulting structural engineers on the World Trade Center."
The concept was not explained TO JOHN SKILLING in April 1964. Speaking to the New York Architectural League in April 1964, the concept was explained BY JOHN SKILLING.
#51. To: nolu_chan, ALL (#49)
They claimed that the building would withstand a hit by a Boeing 707 at 600 mph.
Maybe they lied,
or maybe they actually designed the WTC to sustain a hit by the largest jetliner then in the sky going at 600 mph.
#52. To: BeAChooser (#51)
"You tried to pull a fast one here, NC, AND YOU GOT CAUGHT."
#53. To: BeAChooser (#51)
(Edited)
A white paper released on February 3, 1964 states that the Towers could have withstood impacts of jetliners travelling 600 mph -- a speed greater than the impact speed of either jetliner used on 9/11/01.
Like All Skyscrapers, the Twin Towers Were Over-Engineered One aspect of engineering that is not widely understood is that structures are over- engineered as a matter of standard practice. Steel structures like bridges and buildings are typically designed to withstand five times anticipated static loads and 3 times anticipated dynamic loads. The anticipated loads are the largest ones expected during the life of the structure, like the worst hurricane or earthquake occurring while the floors are packed with standing- room-only crowds. Given that September 11th was not a windy day, and that there were not throngs of people in the upper floors, the critical load ratio was probably well over 10, meaning that more than nine-tenths of the columns at the same level would have to fail before the weight of the top could have overcome the support capacity of the remaining columns.
There is evidence that the Twin Towers were designed with an even greater measure of reserve strength than typical large buildings. According to the calculations of engineers who worked on the Towers' design, all the columns on one side of a Tower could be cut, as well as the two corners and some of the columns on each adjacent side, and the building would still be strong enough to withstand a 100-mile-per-hour wind. 7 Also, John Skilling is cited by the Engineering News Record for the claim that "live loads on these [perimeter] columns can be increased more than 2000% before failure occurs." 8
#54. To: BeAChooser (#51)
Post 53 and the information at the link in it sez you are busted, booby.
#55. To: nolu_chan (#50)
Seems to me that BAC has a reading comprehension problem. Not surprised, I would imagine many believers of the government theory are similarly challenged.
This is just the way BAC operates. The concept was explained to the public in January 1964 and according to BAC it was first explained to the chief structural engineer in April 1964 - only in BAC world.
God is always good!
"It was an interesting day." - President Bush, recalling 9/11 [White House, 1/5/02]
#56. To: BeAChooser (#51) (Edited)
Why the bloody hell would they use a sped close to the V1 of the aircraft? (The gear and flaps up stall speed) The model best suited to use to engineer to withstand impact of an aircraft would be cruise speed. The Vno and or Vmo would be much more logical a standard to use in engineering models. (Vno-Normal Operating Speed, Vmo-Maximum Operating Speed)
#57. To: BeAChooser (#51)
nud·nik also nud·nick(ndnk)
n. Slang
An obtuse, boring, or bothersome person; a pest.
#58. To: nolu_chan, ALL (#50)
It's sad that you resort to this sort slimy language and innuendo. It is an indication that you know your arguments and assertions are without any real merit. Robertson was, according to numerous credible sources, the lead structural engineer. Not Skilling. Skilling just owned the company. He was not the project manager ... the person most intimately familiar with the design and most influential in determining the loads to which it was designed. Robertson was. Robertson was at the location where the design team worked ... NYC. Not Skillings. Robertson says the towers were DESIGNED for a low speed plane impact. Skillings did an ANALYSIS (even he called it that in his 3 PAGE White Paper) of a high speed plane impact. There is a difference between design and analysis. The analysis showed the towers would survive the crash. But that is not unexpected if the towers were designed for a low speed impact, given the sort of safety factors involved in design. To claim the towers were designed for a high speed impact is simply dishonest. To claim they were designed for the fire that would follow a plane impact is dishonest. So do you want to make those claims, NC? Thank you for catching that. I badly misread that quote. I'm embarrassed to have made that mistake. You see, I have no problem admitting when I'm clearly wrong. How about you? And never the less, Skillings white paper is dated February 3 1964. It's difficult to imagine that he'd have been able to do an ANALYSIS on anything less than an already completed design and conclude the towers would survive. It's difficult to believe that he was able to complete and document such a complex analysis in less than a month. Thus, it's difficult to believe that the major structural elements weren't already designed by January 1st 1964. Now here is another source for consideration: http://wtc.nist.gov/pubs/NISTNCSTAR1-1.pdf "For the design of the WTC towers, which began in 1962, the Port Authority in May 1963 instructed the architect and engineers to prepare their designs of WTC 1 and WTC 2 to comply with the NYC Building Code."
Let me explain how bareback rider changes
Speaking to the New York Architectural League in April 1964, the concept was explained BY JOHN SKILLING.
---------------------------------------------------------
Aren't you lucky. You get to receive one of the 15 posts I'm allowed each day.
#59. To: BeAChooser (#58) (Edited)
And when your words are shown not to have merit and to be erroneous, you pretend that that did not happen. People get angry and frustrated with you because you do not dialog in good faith. You are brainlessly and reflexively defending everything and anything the current administration says happened 9-11. If you were dialogging in good faith, you would not be so black and white in your alleged opinions. BAC, the designated 4UM false flag op cheerleader.
"It's sad that you resort to this sort slimy language and innuendo. It is an indication that you know your arguments and assertions are without any real merit."
#60. To: Ferret Mike (#59)
Damn, that hurts to watch, especially since my kid is the captain of the school cheerleading squad. lol
A new truth movement friendly digg type site: Zlonk it!
#61. To: Critter (#60)
Yep. I feel sorry for that girl at the end particularly. ;-)
#62. To: BeAChooser (#58)
You see, I frankly don't care what this report said unless you can explain away all of the above. Because the proof is in the pudding. Bush was right. This report was wrong. And didn't you know? Aligyrl got the boot. BeAChooser posted on 2004-05-13 00:53:27 ET http://libertypost.org/cgi-bin/readart.cgi?ArtNum=24590&Disp=26&Trace=on#C26 So, do you still believe the severely and conclusively debunked Saddam/al Qaeda connection? You sure like conspiracy theory when it involves the death of Ron Brown or this ridiculous and debunked connection between Saddam and al Qaeda.
26. To: wbales1 (#25) Explain the presence of al-Zarqawi in Baghdad after 9/11. Explain his being allowed to conduct operations from Baghdad, including the assassination of our ambassador to Jordan. Explain his connection to the al-Qaeda camp in Northern Iraq ... a camp where it was proved after the war they were working with ricin. Explain his trip to Europe after visiting this camp when he visited two al-Qaeda cells (one in England, one in France) that when later broken up were found to be planning ricin attacks on civilians. Explain the al-Qaeda captured in Jordan that just confessed to planning a chemical attack (which included the use of VX) and who say that al-Zarqawi was the mastermind behind the plot and that they trained for the attack IN IRAQ. Explain Kay's conclusion that WMD components were transported from Iraq to Syria right before the war based on Iraqi interrogations and other data (such as photos and sources within Syria). Explain the murders of so many Iraqi scientists that were seen to be cooperating with Kay's effort to locate the WMD. Explain the intercepts (some played by Powell) that suggest Iraqis had nerve agents and wished to hide them. Explain the VX counteragents found in the possession of the Iraqi military. Explain the just discovered document that suggests Atta did indeed meet with Iraq intelligence just before 9/11. Explain the coincidence in location and time between the first anthrax case and the hijackers. Explain the CIA's list of 50 al-Qaeda / Iraq linkages that was published by the Weekly Standard. etc. etc. etc.
#63. To: Ferret Mike, nolu_chan, ALL (#59)
You seem to be the one doing the cheerleading (for NC) here. That is, unless you'd like to make a real contribution to the discussion. Tell us, FM, how did Skillings do an analysis to end all analyses (that's what the CT community claims ... right?) and document it on February 3, 1964, if the design wasn't completed until later in 1964 as nolu_chan would have us believe?
BAC, the designated 4UM false flag op cheerleader.
---------------------------------------------------------
Aren't you lucky. You get to receive one of the 15 posts I'm allowed each day.
.
.
.
Comments (64 - 196) not displayed.
Top • Page Up • Full Thread • Page Down • Bottom/Latest