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Whoever rebuilds on the WTC site will assume an awesome responsibility.
By Philip Nobel
January 2002
However it is hidden, however it is channeled, construction is about
weight. With a rudimentary knowledge of structures, one can imagine the
weight of a building--casually measured by engineers in units of 1,000
pounds--and the opposing strength of the steel within it, braced against
bending and twisting, bolted or welded into a network that can support
itself. Whatever live loads get piled on, whatever predictable stresses
it encounters, a structure bears weight by bringing every pound back
down to its foundations.
I knew--first because I was told and later because I saw them
unpredictably stressed--that the strength of the twin towers was in
their skins; that each of the closely spaced mullions bordering the
narrow windows concealed a hard-working column loaded with the
accumulating weight of 110 floors; that the whole skein was bound
together laterally to form a steel tube, rigid but designed to bend in
the wind. Much of that was plain to see--it's hard to hide the structure
of a tall building--but in one place the structural logic went mad.
Remember the way the buildings opened up at the lobby floors, as the
minor columns in the facade were gathered into those distinctive
mega-columns like branches to a trunk or fingers to a hand? The
buildings' detractors noted--and note still--that the resulting walls of
ogive-arched windows were a fey conceit, a kind of desultory proto-Pomo
Gothic that was carried through in the self-conscious cloister of the
World Trade Center's lower outbuildings. I always thought they missed
the point by bringing art history to the problem; the treatment of the
tower bases was a bravura structural move of unbelievable power. After
distributing the unimaginable weight of each building into manageable
loads and bringing them almost to the ground--almost--what rational mind
would recombine those loads at the very point where they were heaviest
and then set it all off by stretching great panes of glass in between?
With a very human spark--joyous, perverse--the engineers made the
structure visibly uncanny. Twice.
There were other effects of the twin towers that forced one to choose a
response to the spectacle they created: their height (do I shrink or
soar?), their ubiquity (a blot or a totem?). But the structural dare
behind the funny Gothic stylings was the litmus test. It made the towers
more than just big; it put them, with long bridges and tall dams, in a
special exalted class of man-made things: to doubters, a hubristic
taunt; to believers, the technological sublime.
That touch of Babel doomed the towers--it made them a target. As we all
remember, last year on September 11 the towers burned, then collapsed,
and many, many people--how many we still don't know--lost their lives.
I'm taking the story back to this point because it has since become
clear that some people might forget. On the real estate front,
ominously, it has been business as usual. Just after the attacks Larry
Silverstein, the leaseholder for the World Trade Center, proposed a rote
rebuilding scheme, and a tasteful month or so later he quietly announced
the appointment of two accomplished but uninspiring New York architects,
David Childs and Alex Cooper. The proposal now on the table calls for
four 50-story buildings and space for a memorial. But it is wishful to
think that the memorial can be segregated from the big office buildings
that will surround it; the whole project, from conception to ribbon
cutting, sidewalk to skyline, will bear the burden of honoring the
people who died there--all but ten.
There is no reason to reflexively damn this first step. It will be a long
time before we see new buildings, and many around town feel that the
Silverstein plan might just be the first sacrifice on the altar of civic
opinion. But the current team (and other architects) should keep one
thing in mind: this is not your typical 16-acre development parcel.
People sometimes need images to understand large numbers, but respect
and superstition prevent us from describing the deaths as we would less
sacred tallies--stretching them across the country or piling them to the
moon. So let's try weight. Assume an average of 150 pounds per person
and round the dead to a safe 4,000: you'd get 600,000 pounds, the total
human load on the structures at the moment they fell. For those of you
who habitually scan past numerals, that's six hundred thousand pounds.
How heavy is that? Heavier than the weight of the standing towers.
Lighter than the weight on the shoulders of those who rebuild there.
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