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RE: WSJ's interview with WTC's designer

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I posted this a couple of times but apparently it didn't get delivered
(based on the discussions still going on about it and the fact that I didn't
get it at my AOL address). It could have been due to the size. So, I
massaged it a little bit and here it goes again. It's a cut and paste from
the WSJ site:

Twin Tower's Chief Engineer Stands Up for His Masterpiece

MANCHESTER, N.H. -- Until this past weekend, the principal engineer of the
World Trade Center had said little publicly about the total destruction of
his signature work.

But 73-year-old Leslie E. Robertson broke his silence at a gathering of
fellow structural engineers here, reviewing the project that he began as a
34-year-old wunderkind. What began as a matter-of-fact slide presentation
soon became an emotional experience.

Mr. Robertson began his review by flicking through slides of prefabricated
exterior panels being hoisted into place in the early 1970s. Gripping the
lectern, he faltered. "Oh boy," he said, bowing his head. He gathered
himself. "Next slide."

He used a laser pointer to highlight grim photos of Ground Zero: exterior
panels torn into jagged sections, twisted steel columns, towering piles of
rubble. The commentary continued, like a medical examiner detailing an
autopsy. "Here you see classical tension failure. Next slide. You can see
the columns displaced. Welds are sheared off. Classical failures. Next

Then came the question-and-answer period. "Is there anything you wish you
had done differently in the design of the building?" one engineer called out
abruptly. The room fell silent. Mr. Robertson paused and scratched his head.
"I guess I wish I had made it stand up" longer, he said, his voice trailing
off. "I mean, every man was
important … " He stood alone at the lectern and wept. Another
engineer, his voice breaking, called out: "I think you did a great job." The
audience burst into passionate applause.

On Sept. 11, Mr. Robertson was in Hong Kong and couldn't return to the U.S.
for several days. He gave his slide presentation at a long-planned meeting
of the National Council of Structural Engineers Association. His previously
scheduled topic -- the design of a building in Shanghai planned to be about
200 feet taller than the World Trade towers -- was moved to a later hour, to
be preceded by one deemed more of the moment: "The Design, Construction and
Collapse of the World Trade Center."

Mr. Robertson's views are much sought-after as architects, engineers,
contractors and scholars draw lessons from the performance of the World
Trade Center buildings in the face of jetliners smashing into them and fires
reaching 2,000 degrees Fahrenheit. The issues up for debate range from how
tall is too tall to the type of fireproofing to be applied to steel columns.

A team of engineers led by W. Gene Corley, senior vice president of
Construction Technology Laboratories Inc., Skokie, Ill., who investigated
engineering issues following the Oklahoma City bombing of 1995, will lead a
review of the Twin Towers' performance on behalf of the Federal Emergency
Management Agency. He says
an initial assessment indicated that the buildings "performed well," in that
they didn't collapse immediately. "That did give people enough time to get
out," he says. One tower stood for about 47 minutes after impact; another
stood for about an hour and 40 minutes.

Mr. Roberston says that he and his firm, Leslie E. Robertson Associates
RLLP, are cooperating with Mr. Corley's group. He also says he expects his
New York-based firm, along with others, will be named in liability suits
related to the buildings' collapse, as occurred after the 1993 bombing. He
says any potential suits would be meritless. He is proud of his and his
firm's work on the Trade Center, he says, noting that the towers were still
standing after roughly two-thirds of their columns, the main vertical
supports, had been destroyed on each building-face hit.

A native of Manhattan Beach, Calif., Mr. Robertson earned a science degree
at the University of California, Berkeley. After engineering jobs in
Venezuela and elsewhere, he says, he ran out of gas and money in Seattle on
a cross-country drive in 1958 and took a job with an engineering firm named
Worthington-Skilling. He joined that firm, he says, because it was the first
to offer him an advance.

Worthington-Skilling was then a small but growing regional firm. But a
partner, John B. Skilling, forged a relationship with architect Minoru
Yamasaki that woke things up in a big way. In the early 1960s, Mr. Yamasaki
won a competition to design the World Trade Center and hired the Seattle
firm to handle the engineering.

Mr. Robertson, who had never designed a building higher than 20 stories,
emerged as the engineer of record for the most high-profile project of its
day. He credits Mr. Yamasaki, who died in 1986, with assigning him the job,
though he says he wasn't afraid to play hardball. When an older engineer was
originally assigned to help lead the project, Mr. Robertson threatened to
stay home. "They dispensed with the older guy," he says.

Messrs. Robertson and Skilling came to a parting of the ways in 1983, when
the firm split to become Leslie E. Robertson RLLP, based in New York, and
Skilling Ward Magnusson Barkshire, based in Seattle. In subsequent years,
the engineering of the World Trade Center became the subject of a tug-of-war
over credit between partisans of Mr. Skilling, who died in 1998, and those
of Mr. Robertson, says Jon Magnusson, chairman and chief executive of
Skilling Ward. He calls the differences "unfortunate."

In any case, the project consumed more than 10 years of Mr. Robertson's life
and occupied his firm with maintenance issues until last Sept. 11.
Breathtakingly bold from a technical standpoint, the building of the towers
was studied by engineers world-wide. Innovations and advances included
everything from its externally braced tubular framing system to the use of
computerized punch-card system to order structural steel.

Since the destruction, Mr. Robertson says he has had trouble sleeping,
wondering if there had been a way to make the buildings stand for "those
extra minutes." He wonders about cylindrical trusses bracing the floors;
T-shaped trusses are easier to coat with fire protection. But the round
design was approved as part of the give-and-take of a construction project.
"I didn't like it," he said, but added that the design had performed well in
fires over the years.

Mr. Robertson said he has experienced a range of emotions -- anguish, doubt,
pride, guilt. But in the end, he said, the towers "stood up under conditions
far in excess of what they were designed for."


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