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Dismissing the exemplary
performance record of high-rise steel structures in "pure"
fires, attendees of a government-sponsored workshop on fire
safety voted for a blue-ribbon committee to develop an integrated
methodology for performance-based design of fire protection
of steel frames. The recommendation topped a wish list that
included an interest in developing models for structural performance
under fuel loads, with a multihazard design approach.
With
looming cutbacks, "what you do [at this workshop
on fire safety for structural steel in high-rise buildings]
will help us focus on issues critical to the construction
industry." Bement |
Action on the list might be slow.
"What you do here will help us focus on issues critical
to the construction industry," said Arden L. Bement Jr.,
director of the National Institute of Standards & Technology,
which sponsored the Feb. 5-6 workshop in Gaithersburg, Md.
Bement is seeking ways to cut staff and delay research to
absorb budget cuts.
Some attendees think research into
fire protection of structural steel high-rises should not
be a priority. According to a recent NIST-sponsored survey
by Hughes Associates Inc., of the 17 buildings four stories
or taller that suffered structural damage from fires not a
consequence of terrorist attacks since 1970, only two had
steel frames.
The
terrorist attacks on Sept. 11, 2001, "accelerated
the effort and importance" of NISTs interest
in structure-fire interaction, which predates 9/11
Grosshandler |
The study also looked at the four
steel frames of the World Trade Center, destroyed by attacks
on Sept. 11, 2001. But "our interest in structure-fire
interactions predates 9/11," said William L. Grosshandler,
chief of the fire research division at NISTs Building
and Fire Research Laboratory. "The events of 9/11 [only]
accelerated the effort and importance" of the labs
pre-9/11 plan, he said.
Sept. 11 should not and cannot
be a standard for design, said Jonathan C. Siu, principal
engineer for Seattles Dept. of Planning and Devel-opment.
"Do we want to change code requirements based on one
data point?" he asked.
Each year, 3,000 people die in
building fires that cause $5 billion in damage, said Grosshandler.
But he later noted that most deaths are in residential buildings
and not high-rises. And few deaths are caused by steel high-rise
collapses, said others.
The 50 attendees included nine
from fire-protection materials suppliers, eight from NIST,
seven from fire protection engineering firms and seven from
associations and code councils. There also were five structural
engineers, two public owners, three academics and five from
the Civil Engineering Research Foundation, organizer of the
$75,000 workshop.
Several attendees claimed a pure
fire catastrophe is an accident waiting to happen, thanks
to recently reduced requirements for passive fire protection.
They call for improvements in fire modeling and structural
response, made possible by advances in computing power.
"With development of performance-based
codes, there has been a return to explicit discussion of objectives...and
performance requirements," said Frederick W. Mowrer,
a professor of fire protection engineering at the University
of Maryland, College Park. "We need to adapt current
performance methods for natural hazards for better application
to fire," he said.
The groups other recommendations
are to determine "precision and bias" of existing
fire-resistance test methods; to define performance objectives
for fireproofing materials and systems; to review and assess
trends to reduce passive fire protection; and to develop and
correlate models with fire test data.
In its vote for action, the group
showed little interest in determining whether current codes
are adequate. In reaction to that, one structural engineer
warned: "If you want to do advanced fire engineering,
you need to show the need and economic basis for it and the
real increase in safety. If not, the effort is doomed to fail."
Those calling for change seem to
advocate developing a new engineering discipline that would
involve fire protection and structural engineers. Currently,
architects specify fire protection and life safety systems.
There were no design architects in attendance.
"It is important to keep in
mind that society has a finite amount of resources to devote
to improving overall building safety," said Robert J.
Wills, a regional director in the Birmingham, Ala., office
of the American Iron & Steel Institute. "Our ultimate
goal should be to allocate resources in a focused, rational
manner that will lead to real improvements in life safety
and property protection."
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