query.nytimes.com/gst/fullpage.html?res=
September 20, 2001
A NATION CHALLENGED: THE SKYSCRAPERS;
Engineers Say Buildings Near Trade Center Held Up Well
By ERIC LIPTON AND JAMES GLANZ
Though buildings near the World Trade Center show evidence of damage like blown-out windows or gashes on their facades, none appear to be slumping, leaning or subsiding, and none are in danger of imminent collapse, engineers said yesterday after a detailed series of inspections.
Isolated structural repairs will be required on at least three large office buildings: Bankers Trust, 30 West Broadway and 3 World Financial Center. Many others, like 22 Cortlandt Street, will require more modest exterior repairs, as well as extensive work to windows, heating or ventilating systems, or other damaged parts.
But it is unlikely that any of these or other nearby buildings will need to be demolished, said Richard Tomasetti, president of LZA/Thornton-Tomasetti, the engineering firm the city hired for the assessments.
''All of them, in my opinion, there's no reason in the world that they can't be saved,'' Mr. Tomasetti said. ''I can't tell you what the owners will decide for the few buildings with limited structural problems, but these buildings don't need to come down.''
Two reporters from The New York Times obtained a copy of the city's preliminary assessment of 195 buildings in the area yesterday, and were allowed to view structures in and around what has come to be called ground zero. The contrasts there evoked the capricious power of an earthquake, with structurally sound buildings standing across the street from smoking mounds of rubble five or six stories high.
Through much of the area south of Park Place, north of Albany Street and west of Broadway, there are stretches where hundreds of windows facing the towers have been blown out. Roofs have been damaged from falling debris, including airplane parts found on the Federal Office Building at 90 Church Street and another building across Barclay Street, at 100 Church Street. Other building exteriors are singed by fire or just caked with soot.
But the preliminary results of the city's detailed building-by-building assessment of the area support the conclusion that while damage to facades and interiors is occasionally severe and plainly visible, many of the buildings could be occupied in several weeks to several months. There is no evidence that any buildings have been compromised structurally in a way that would require demolition.
In part, the survey suggests, that is because the twin towers collapsed almost straight downward, a circumstance that the engineers said might have reduced the death toll from the terrorist attack.
''It's like controlled demolition,'' said Matthys Levy, a founding partner at Weidlinger Associates, a structural engineering firm in New York. Mr. Levy, the co-author of ''Why Buildings Fall Down'' (Norton, 1992), said the collapse of the towers was ''an uncontrolled demolition project, but it acted like a controlled demolition project.''
If the buildings had tipped or tumbled sideways instead, Mr. Levy said, ''you would have seen tremendous damage outside the zone, and you would have had those buildings possibly collapse.''
The eight-page Department of Buildings survey of 195 structures in and around the World Trade Center complex again and again reports ''building is safe'' or ''minor cleanup required'' or ''O.K. to occupy.'' Buildings with those kinds of findings include 4 World Financial Center, occupied in large part by Merrill Lynch & Company. and 75 Park Place, the home to the city's Office of Management and Budget.
Even 1 Liberty Plaza, a building with more than 50 stories across the street from 4 World Trade Center, which is partially collapsed, is listed as ''structurally sound, including facade,'' despite rumors during the last week that it was nearing collapse. (The 4, 5 and 6 World Trade Center buildings are largely wrecked and will have to be demolished, an engineer said.)
The Millenium Hilton Hotel is also structurally sound, the survey says, though it is missing some front windows and its lower facade is damaged.
These assessments do not mean that tenants will necessarily be able to move back soon. The 75 Park Place building needs an extensive cleanup, as does 4 World Financial Center, where employees may not able to return for two to three months, a Merrill Lynch spokesman said.
Engineers also cautioned that after the main structural questions have been addressed, a wide range of other cleanup and repair work would remain, including repairing or replacing heating, cooling and ventilation systems; replacing hundreds of windows; restoring electricity and installing or repairing fire alarms and security systems.
''Merrill Lynch will not put one person back into any of our buildings until we are absolutely sure that they will be safe,'' said Rich Silverman, a Merrill Lynch spokesman.
John F. Hennessy III, the chairman of Syska and Hennessy, a engineering firm that specializes in mechanical and electrical systems, said the problems inside the buildings were likely to be similar to those encountered after the 1993 bombing of the trade center.
''One of the big problems there was getting the building clean because there was a tremendous amount of smoke that went through the building,'' said Mr. Hennessy, whose firm worked on the trade center after the bombing and has been hired to rebuild systems in the interior of the Pentagon.
The appearance of the residential buildings where thousands of people live south of Gateway Plaza in Battery Park City supports Mayor Rudolph W. Giuliani's assertions that they have suffered no major damage, although dozens of windows on the east facade of Gateway Plaza have been blown out.
On the northern edge of Battery Park City near the Embassy Suites Hotel and the movie theater, there is no apparent structural damage.
A handful of buildings have not been inspected thoroughly yet, including three on Cedar Street, in part because of their proximity to the center of the impact zone.
The effort to assess the damage to the 195 buildings in the area has involved about 100 engineers making the inspections, officials said. On average, about 2,000 workers, using everything from large cranes to metal cutters, are at the site each day, removing debris and preventing damaged facades from tumbling. For example, a beam from one of the World Trade Center towers pierced the facade of 3 World Financial Center, and workers have tied it down until it can be safely removed.
The building assessment and cleanup effort is led by Michael Burton, executive deputy commissioner, of the city's Department of Design and Construction, in cooperation with the Port Authority of New York and New Jersey and private sector consultants.
The command center of the project is on the second floor of Public School/Intermediate School 89, at the intersection of Chambers and West Streets. Boxes of hard hats and goggles sit in the entrance hallway.
Six major construction companies in the New York region have been recruited to help with the work: Tully Construction, Amec Construction Management, Bovis Lend Lease, Turner Construction, Plaza Construction and Tishman Construction. LZA/Thornton-Tomasetti Group is overseeing the individual building assessments. Mueser Rutledge, another engineering consulting company, is working to ensure that the massive underground walls that surround the World Trade Center complex and hold back the Hudson River are not compromised.
This work is under way as firefighters continue to douse smoldering debris. In a classroom at the school used by the engineers and city officials as a meeting room, bins of colored building blocks sat on shelves and children's books sat abandoned. A large spiral notebook propped up in one corner had been carefully lettered with this message:
''Jack be nimble,
Jack be quick,
Jack jump over the candlestick.''
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