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Here is the test of the article:

In assessing the rubble of the World Trade Center, architects, engineers and
scholars are finding lessons that could affect the future of skyscrapers --
from their height to the width of interior stairwells.

Designers, for instance, are now looking at the building codes of Britain
and some Asian countries that require separate stairways and freight
elevators for rescue personnel, along with widening landings, all to avoid
crowded scenes that investigators say hampered rescue efforts in the
100-story World Trade towers.

Also attracting some interest: so-called refuge floors. Required by building
codes in China, the Philippines and elsewhere, the open-air floors are
spaced 10 to 12 floors apart, allowing inhabitants to breathe while waiting
for rescue personnel. Stairwells are required to open onto the floors, which
were conceived in part to avoid scenes such as occurred during the 1993
World Trade Center bombing when office workers smashed windows to escape
smoke drawn up through the building from a "chimney effect" caused by the
blast. The challenge, says T.J. Gottesdiener, a managing partner of
architectural firm Skidmore, Owings & Merrill LLP, "is separating what is
appropriate from what is a reaction." His firm had no role in building the
World Trade towers.

The deliberations come despite a widely held belief that designing buildings
to withstand the impact of airplanes is a waste of resources that are better
spent elsewhere, including on airport security. Despite the recent attack,
many designers don't believe high-rise buildings themselves will become less
desirable or useful.

0See plans for the International Financial Center in Shanghai.

"Are we not going to build buildings with five sides anymore because they
hit the Pentagon?" asks Carol Willis, an architectural historian and
director of the Skyscraper Museum, in New York. "We're asking the wrong
questions."

Still, some lessons are obvious. The attack dealt a fatal blow to fledgling
attempts to revive the monumentalist school of American architecture last
seen with the completion of Chicago's Sears Tower in 1974. Nascent plans --
in Chicago, Donald Trump's plans for the Sun-Times property, as well as a
much-discussed 2,000-foot tower in Miami -- are less likely to proceed,
certainly on such a grand scale. So, too, does even the idea of rebuilding
the World Trade Center towers to their former height. "I don't think,
frankly, we're going to build back the Trade Center to 110 floors," Mr.
Gottesdiener says. "People won't be comfortable there."

Still, some developers are trying to proceed with business as much as usual
as they can muster. The developer of the Miami project, Guillermo Socarras,
is still trying to arrange financing, according to a spokesman, who added,
"he's not going to allow 19 or 19,000 terrorists to change a project he's
worked on for three years."

Other lessons will be less noticeable -- and will take longer to have
effect. Two teams of engineers will review the so-called performance of the
Pentagon and the Trade Center and surrounding buildings and issue a report
to the Federal Emergency Management Agency and other interested parties. The
review will explore the buildings' overall resistance to collapse from the
moment of collision, as well as the effects of the fire. The report, which
won't be ready for 18 months or so, will likely result in recommended
changes in model buildings codes. Possible areas under review include the
strength of columns and beams, and the number and width of stairwells.

At a conference of structural engineers held last weekend at a rustic New
Hampshire inn, engineers puzzled over the problems posed by the destruction
of support columns after the two jetliners collided into the towers. They
also studied the effect of burning jet fuel on fire-proofing systems, and
the subsequent "progressive collapse," when the steel columns finally gave
way.

Among other issues, engineers said, the fire grew hot faster, burned far
hotter and stayed hot longer than the 1,400 degrees and higher found in
standard "time-temperature" tests used to rate protection materials.
Engineers said the standards themselves, which approximate the heat of
burning desks, carpets and paper, may have to be changed.

If there is one thing to be considered a failure in the Trade Center's
design, it was that "people in the floors above the crash had limited
ability to escape," said Ron Hamburger, chief structural engineer for ABS
Consulting, New York, and a member of the performance-review team. Mr.
Hamburger's firm should know. The firm had offices on the 91st floor of the
North Tower. Employees found two stairwells blocked by debris, but all 16
escaped safely down a third.

The towers were believed to have been the first to rely on "shaft-wall"
interior cores, made of gypsum-based wallboard instead of harder materials,
masonry or reinforced concrete. The shaft-wall design was considered a
breakthrough at the time, favored for its fire resistance and air-tight
qualities. A question today is whether abandoning shaft-wall construction is
worth the additional weight and cost.

Leslie E. Robertson, who directed the structural design of the Trade Center,
said he would be "astonished" if codes are changed to require harder
interior cores. The proper response, he says, "is not making buildings
resistant to the airplane, but to keep the airplane from running into it."


> -----Original Message-----
> From: Rbengrguy(--nospam--at)aol.com [mailto:Rbengrguy(--nospam--at)aol.com]
> Sent: Wednesday, October 10, 2001 10:02 AM
> To: seaint(--nospam--at)seaint.org
> Subject: WSJ
>
>
> Attention  SEAINT LIST
>
> I've just received word  that
>
> Wednesday's Wall Street Journal reports on Les Robertson's talk
> at the NCSEA meeting. Plus other structural stuff. Well worth
> getting a copy...
>
> ( I haven't seen it  -  but have to  get a copy)
>
> Bob   Johnson
> SEAOI
> 203  N.  Wabash    Suite 2010
> Chicago,   IL  60601
>
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