Willravel

I've been glued to the HC/TLC/PBS since they started brining forward reports and specials about the subject. These is a lot of intersting speculation on these specials, and I'd reccoment to anyone to watch them.

Oh. Okay. Ty.

Calculations done by an independant research team. I'll get into that later.

No one really seems to know about building 7. It's actually a pretty big deal, despite the fact that no major news network has covered it.

Building 7 colapsed. Let's start here. According to every source available, fire colapsed this building. Chapter 5 of FEMA's World Trade Center Performance Study is what I used as the primary source of the information on what officiall happened. This question would appear to be the greatest in engineering history. In over 100 years of experience with steel frame buildings, fires have never caused the collapse of a single one, even though many were ravaged by severe fires. Indeed, fires have never caused the total collapse of any permanent steel structure.

What was done to answer this most important question? The only official body that admits to having investigated the curious collapse of Building 7 is FEMA's Building Performance Assessment Team (BPAT), which blamed fires for the collapse but admitted to being clueless about how fires caused the collapse.

People who have seen buildings implode in controlled demolitions are unlikely to be as challenged as FEMA's team in understanding the cause of Building 7's collapse. They will notice, upon watching the videos, that Building 7's collapse showed all of the essential features of a controlled demolition.

Despite having the appearance of a controlled demolition, is it possible that Building 7 could have been destroyed by some combination of damage from tower debris, fuel tank explosions, and fires? Let's consider the possible scenarios.

The evidence does not support the idea that Building 7 was damaged by fallout from the tower collapses, nor that there were diesel fuel tank explosions. Fires were observed in Building 7 prior to its collapse, but they were isolated in small parts of the building, and were puny by comparison to other building fires. Let's imagine, contrary to the evidence, that debris from the tower collapses damaged Building 7's structure, that diesel fuel tanks exploded, and that incredibly intense fires raged through large parts of the building. Could such events have caused the building to collapse? Not in the manner observed. The reason is that simultaneous and symmetric damage is needed to produce a collapse with the precise symmetry of the vertical fall of building 7. This building had 58 perimeter columns and 25 core columns. In order to cause the building to sink into its footprint all of the core columns and all of the perimeter columns would have to be broken in the same split-second.

Any debris from the towers impacting Building 7 would have hit its south side, and any columns damaged by it would almost certainly be perimeter columns on its south side. Any fuel tank explosion would only be able to damage nearby structure. The rapid fall-off of blast pressures with distance from the source would preclude any such event from breaking all of the columns in the building.

(Furthermore the very idea of a tank of diesel fuel exploding taxesthe imagination, since diesel fuel does not even begin to boil below 320 degrees F.) Fires have never been known to damage steel columns in highrise buildings, but if they could, the damage would be produced gradually and would be localized to the areas where the fire was the most intense.

No combination of debris damage, fuel-tank explosions, and fires could inflict the kind of simultaneous damage to all the building's columns required to make the building implode. The precision of such damage required to bring Building 7 down into its footprint was especially great given the ratio of its height to its width and depth. Any asymmetry in the extent and timing of the damage would cause such a building to topple.

Moving on th the rubble...Engineering is a science that melds theory and experience to create robust structures. Unintended structural failures are rare events that warrant the most careful scrutiny, since they test engineering theory.

That is why the NTSB carefully documents aircraft crash scenes, and preserves the aircraft remains, frequently creating partial reconstructions in hangers. If an investigation reveals a mechanical or design fault, the FAA usually mandates specific modifications of equipment or maintenance procedures system-wide, and future aircraft are designed to avoid the fault.

Unintended structural failures are less common in steel frame highrises than in aircraft. Being the only such building in history in which fire is blamed for total collapse, Building 7's remains warranted the most painstaking examination, documentation, and analysis.

Building 7's rubble pile was at least as important as any archeological dig. It contained all the clues to one of the largest structural failures in history. Without understanding the cause of the collapse, all skyscrapers become suspect, with profound implications for the safety of occupants and for the ethics of sending emergency personnel into burning buildings to save people and fight fires.

There was no legitimate reason not to dismantle the rubble pile carefully, documenting the position of each piece of steel and moving it to a warehouse for further study.

No one was thought buried in the pile, since, unlike the Twin Towers, Building 7 had been evacuated hours before the collapse.
The pile was so well confined to the building's footprint that the adjacent streets could have been cleared without disturbing it.

Yet, despite the paramount importance of the remains, they were hauled away and melted down as quickly as possible. The steel was sold to scrap metals vendors and most was soon on ships bound for China and India. Some of the smaller pieces and a few token large pieces of steel marked 'save' were allowed to be inspected at Fresh Kills landfill by FEMA's BPAT volunteers.

This illegal evidence destruction operation was conducted over the objections of attack victims' family members and respected public safety officials. Bill Manning, editor of the 125 year old Fire Engineering Magazine, wrote in an article condemning the operation:
"Did they throw away the locked doors from the Triangle Shirtwaist fire? Did they throw away the gas can used at the happy land social club fire? ... That's what they're doing at the World Trade Center. The destruction and removal of evidence must stop immediately."

Dr. Frederick W. Mowrer, an associate professor in the Fire Protection Engineering Department at the University of Maryland, was quoted in the the New York Times as saying:
"I find the speed with which potentially important evidence has been removed and recycled to be appalling."

Officials running the "cleanup operation" took pains to make sure the structural steel didn't end up anywhere but in blast furnaces. They installed GPS locater devices on each of the trucks hauling loads from Ground Zero at a cost of $1000 each. One driver who took an extended lunch break was dismissed.

So now we're all wondering about FEMA...The only government entity that purported to examine the collapse of Building 7 was the Building Performance Assessment Team (BPAT) composed of volunteer engineers selected and supervised by FEMA (Federal Emergency Management Agency).

In May of 2002, BPAT published their World Trade Center Building Performance Study. Chapter 5 of the report is devoted to Building 7. The report makes unsubstantiated claims and uses a variety of deceptive techniques to make the total collapse of Building 7 due to fires seem less implausible than it is. A copy of Chapter 5 marked up by an anonymous author exposes many of these deceptions. http://www.wtc7.net/articles/FEMA/WTC_ch5.htm

None of which (furnature, carpets, paper, AIRPLANE FUEL) had the ability to create the heat necessary to melt the steel frame to the extent that the building would colapse, let alone colapse straight down.