When it comes to conspiracy theories and polarized thoughts, few incidents trigger controversy like the 911 collapse of the World Trade Centre and a third building, known as Building WTC 7.
Principle Curator Ian Harvey wrote this story in 2020 about a group of engineers and architects and victim family members who say the scuience doesn’t support the finding of an investigation that claimed fire weakened the structural steel and triggered the floor-by-floor collapse.
It’s important to note that they don’t claim that any group or person deliberately set explosives or did something else to trigger the collapse of WTC7 just that from an engineering and science standard the findings do not hold true and that there was nothing wrong with the integrity of the design or construction of the building.
The Architects & Engineers for 9/11 has filed a Request for Correction with the National Institute of Standards and Technology (NIST) following a new and detailed four-year analysis by a team at the University of Alaska Fairbanks.
It says the World Trade Centre building 7 collapse was a “near-simultaneous failure of every column in the building” and dismissed the NIST finding that heat from the fire caused beams to “walk off” their moorings.
The Sept. 11, 2001 is tragedy of two hijacked planes hitting WTC 1 and WTC2 that morning sent debris tumbling onto WTC and NIST claimed that embers ignited a fire which then caused the 47-storey building to collapse on itself at 5.20 p.m. hours after the initial incident.
“We have filed a request for correction because the NIST report is wrong,” says Ted Walter, spokesperson for group of 3,000 engineers, scientists and architects, including more than a dozen Canadians which paid US$316,000 for the study. “From an engineering perspective it is imperative to understand how and why this building came down under design load conditions.”
The study says NIST made some fundamental errors in how engineers estimated the rigidity of the outside building frame and that the heat generated by the fire did not trigger “thermal movements” at a critical base plate support.
Further, the group, which includes families of those killed, asserts that the investigation is flawed and that the conclusions as to what happened must be based on “science and engineering” and accept that controlled demolition is a plausible cause. For expediency and because it was not hit by a plane, the study looked only at WTC 7 not the other two but AE911T has long claimed all three were subject to something beyond heat induced failure.
“The report notes that the outside frame was more flexible than the inside framing which is where the elevator shafts were,” says McMaster University professor emeritus of civil engineering, Robert Korol, a fellow of the Canadian Society of Civil Engineering one of two peers who reviewed the UAF study. “Under the conditions described the displacement of the outside steel would have been only 1 inch, not the 6.25 NIST claimed and not enough to cause failure.”
Further, he says, the debris from WCT1 which fell 943 feet to WCT 7 did not attain sufficient mass to cause structural damage to the steel in that building.
The bottom line, he says, is that the NIST report is flawed and of no value to future engineering or architectural learning.
The Alaska report adds new momentum to long standing claims by the AE911T that all three of the buildings should not have collapsed in the spectacular and deadly manner they did. Further, and Prof. Korol underlines this, there was nothing in the offices beyond basic desks, chairs, computers and paper that would be of a of such a combustible nature so as to feed a fire and raise the temperature to above 1,400C and melt the steel structure.
“We don’t even know if the steel was fireproofed,” says Prof. Korol.
The group makes no assertion as to why it may have been a “controlled demolition” and says its only interest is in ensuring that there’s no need to rethink the structural steel design of high rises because the design was not at fault.
UAF civil engineering professor Leroy Hulsey, principal investigator, his research assistants, Feng Xiao, now an associate professor at Nanjing University of Science and Technology and Zhili Quan, now a bridge engineer for the South Carolina Department of Transportation, found that the design standard of the building was no exceeded by the fire and that simultaneous and controlled demolition caused the structural steel to fail.
“Fires could not have caused weakening of displacement of structural members capable of initiating any of the hypothetical local failures alleged to have triggered the total collapse of the building,” the report states. “Not could any local failures, even if they had occurred, have triggered a sequence of failures that would have resulted in the observed total collapse.”
The NIST report held that lateral support beams buckled because of thermal expansion from the fire and because they had “nowhere to go” and thus deformed and weakened the structural integrity. Other failures were triggered when joists and means “walked off” their connections, NIST found.
It was also the first NIST finding of a high rise collapse from thermal deformation caused by fire which the 125-page Alaska report disputes.
It presents arguments showing it was a simultaneous global failure not a localized failure causing a domino effect.
Prof. Hulsey et al, argue that the collapse was straight down in a pancake fashion with about 2.25 to 2.5 seconds for free fall acceleration.
“In a typical building collapse (given a localized structural steel failure) WTC7 would be expected to axial rotation and bending of members, resulting in a disjointed, asymmetrical collapse at less than free-fall acceleration,” the report states.
An initial report in 2002 by The Federal Emergency Management Agency (FEMA) pointed to a steel member recovered from WTC 7 with corrosion from a combination of oxidation and sulfidation at 1,000°C, resulting in the formation of a liquid eutectic
“Researchers have hypothesized that the presence of thermate, which is a form of thermite incendiary that includes sulfur, would explain the sulfidation and formation of a liquid eutectic,” the report says noting FEMA found there weren’t enough combustibles to generate enough heat to weaken the steel and speculated diesel fuel stored in the basement was somehow being pumped through severed pipes and fed the flames. However, NIST later dismissed that hypothesis.
The study team undertook extensive computer and physical modeling, paying particular attention to the area around Column 79 which had been identified as the critical juncture of failure.
Their conclusion is that Columns 79, 80, and 81 did not fail at the lower floors of the building and were not subject heat above floor 30 because there were no fires there.
Even if they did, they would not trigger a horizontal progression of core column failures and the team was unable to find any other plausible cause for the progressive sequence of failures. ?