Posted on 04/05/2005 9:48:56 PM PDT by SmithL
NEW YORK - Federal investigators said Tuesday the World Trade Center buildings probably would not have collapsed in the Sept. 11, 2001, attacks if fireproofing had adhered firmly to the columns and floors.
The National Institute of Standards and Technology also concluded that the average survivor took more than double the estimated time to descend emergency stairwells, and that better communication between emergency responders could have saved more lives.
The NIST, which issued three reports on the attacks, did not blame designers or builders for the buildings' collapse. However, Shyam Sunder, who led NIST's fire and safety investigation, said there are now better ways to ensure that fireproofing adheres to steel.
"Even with the airplane impact and jet-fuel-ignited multi-floor fires, which are not normal building fires, the buildings would likely not have collapsed had it not been for the fireproofing that had been dislodged," he said.
The reports are likely to spur debate about how to build safer skyscrapers. Some investigators and rescuers have advocated "fireproof" elevators and stronger stairwells in new high-rises. In theory, fireproof elevators could have taken firefighters to the upper floors and helped people get out faster.
The NIST findings were met with mixture of skepticism and praise from family members of Sept. 11 victims who attended a public hearing on the reports.
Laura Weinberg, whose husband Richard Aronow died in the attack, said she was disappointed with some of the conclusions about design features. "I think they've soft-pedaled the issue of spray-on fireproofing," she said.
But Allan Horwitz, whose son Aaron also died in the attacks, said he was "very pleased" with NIST's work. "It seems to me like they're doing everything they can to find out what happened, why it happened, and how we can prevent it from happening in the future," he said.
The report also found that in Tower 1, it took the average survivor 48 seconds to descend a flight of stairs. This was double the slowest evacuation time estimated in a current fire safety handbook used by engineers who design buildings, the report said.
The report said that some people delayed their evacuation by "milling" in offices, deliberating about what to do, or debating how to find a stairwell.
NIST said the times in the models are based on phased evacuations, not the full-scale evacuation that occurred in the towers. The evacuation models cited in the NIST report are used by architects to calculate how much capacity is needed in stairwells, elevators, and other exit routes.
In addition, the report found that the much-documented problems with radio communication and information-sharing among first responders probably "contributed to the loss of emergency responder lives."
The findings represent NIST's last step before issuing its final recommendations in June, the culmination of exhaustive research and testing that produced 10,000 pages of data.
The official World Trade Center death toll stands at 2,749, including those killed on the two jetliners that hijackers crashed into the buildings.
More lives on the head of the environuts.
The jihad against asbestos is partially responsible.
Soon after the attack, we heard a little about how al-Qaeda had done engineering studies to achieve maximum destructive effect, then we heard nothing more. I would like to see this followed up. Was the change from asbestos on the lower floors to asbestos-free fireproofing on the upper floors a factor in the terrorists' calculations?
And how many people would have died from the asbestos? How many people would have sued the heck out of everyone concerned?
That said, I don't get why these people are complaining. They were only supposed to stand for an hour after taking a hit from a fully loaded 707, the most common airliner of the time. They took hits from far larger airliners and still managed to stand for roughly their design spec time despite stresses far in excess of their design spec. I'd say the designers and the construction workers did an adequate job.
That said, everyone above the impacts was pretty much screwed when the JP4 ignited. When the cement itself is burning.... Their only hope at that point was either parachutes or aerial rescue off the roof, and nobody had either.
Quinn on 104.7 was on that pretty heavy for a while.
Odd, it's pretty clear that the planes did it.
Still wouldn't matter. Trusses are not engineeringly sound in fires. Firemen even state to never trust a truss. It had not inner stregth. The support came from the outer walls of the building. It took the hit, but could not survive the heat from the jet fuel.
And despite all that, the first tower to collapse stood for almost an hour - the second stood for well more than that.
These people have *no* grounds to complain that the WTC didn't function as designed - it functioned well beyond its limits.
The architects have repeatedly stated that they designed it to withstand the impact of a fully-loaded 707.
That said, some reports have estimated peak temperatures at the WTC during the fires at 1400C. I am unaware of any material available at the time of construction that could have been used to insulate the steel or concrete from thermal failure at this temperature.
And, yes, the fuel-air-explosive effect would have blown much of any theoretical fireproofing off the material it was protecting.
There may be "better" ways, but there is NO way any attached fireproofing will stay adhered to steel against a 500 mph spray of airplane parts.
The only thing that would have saved what was left of the towers, in my estimation, would have been a gargantuan active fire suppression system, such as tons and tons of baking soda pressurized by inert gas and water.
Doubt if such a system of that magnitude would ever be installed in a skyscraper.
Now that I read the article my take has changed on it.
- Only three (3) small bolts held each lightweight truss in place
- Two (2) at one end
- Only one (1) at the other end
Less high-strength bolts then fasten the front crossmember on your PU!
When each lightweight truss failed - it could no longer keep the outer perimeter verticle steel from bowing out - then each trusses next to it would fail on each side -
The WTC design was for one reason only - to save money on construction materials and labor and provide more leaseable floor space
The architect was a moron.
The engineers were morons.
Besides failure from dinky lightweight trusses - NYC had OKed cutting the number of elevators and the required solid walls around the elevators and stairs.
"More income" was the reason.
The City of NY and the engineers, architect, builders, Enviro-Nutzie groups, owner would have been tried and found negligent in many other countries.
NYC is not a city where you want to cut safety factors - There is plenty of "cutting" already.
My brother is a construction engineer and contractor - when the WTC got hit in 1993 - recall how long it took for employees to get out then? - I told him it would be hit again and both towers would fail -
For another example in lousy engineering - check out the Greenwich CT Thruway Mianus Bridge failure in the early 1980's - excusers said "time" was a factor - corrupt state (non)inspectors and an idiotic design were the cause -
Yet the old Brooklyn Bridge still stays up.
The Empire State Building took a big hit years ago - it still stands tall.
The WTC was built of bailing wire and cardboard and greed.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.