Report: Towers collapse shocks engineers Posted on Tuesday, September 11 @ 22:47:59 CEST by webmaster

  DETROIT, Sept. 11 (UPI) --
Architects that designed New York's World Trade Center Towers expressed shock Tuesday that the 110-story landmarks in Lower Manhattan collapsed after each tower was struck by a hijacked passenger jetliner.



The World Trade Center was completed in 1976 at a cost of $350 million and one of the towers had survived a 1993 attack by terrorists in an explosives-filled van that killed six people and injured more than 1,000 others.

Lee Robertson, the project's structural engineer, addressed the problem of terrorism on high-rises at a conference in Frankfurt, Germany, last week, Chicago engineer Joseph Burns told the Chicago Tribune.

Burns said Robertson told the conference, "I designed it for a (Boeing) 707 to hit it." "Fire melts steel," Burns told the Tribune, speculating that the impact from the planes had damaged sprinkler systems in both towers.

"You never know in an explosion like that whether they get cut off," Burns said. The World Trade Center was designed by architect Minour Yamasaki, whose Rochester Hills, Mich., firm, Minoru Yamasaki and Associates, is known for its sweeping use of glass.

Yamasaki, who died in 1986, also designed the McGregor Memorial Conference Center at Wayne State University, the Reynolds Aluminum building in Southfield, Mich., and the 30-story Consolidated Gas Co. Building in downtown Detroit.

Terrorists who carried out the 1993 attack on the symbol of America's financial prowess said they had wanted to bring the New York tower to the ground. Near Washington, part of the 6.5 million-square-foot Pentagon collapsed after the nerve center of U.S. military forces was hit by a plane, causing a huge fire.

High rises, office buildings, courts, city halls, museums, sports stadiums and other public buildings were closed coast-to-coast as a precaution. The Mall of America in Bloomington, Minn., the largest shopping mall in the United States, was evacuated after the morning attacks.

"While we have not received any threats we believe this is a prudent precaution," said Maureen Bausch, vice president of marketing and business development.

The Fitzgerald Theater in Minneapolis canceled a Talking Volumes Book Club event featuring author Salmon Rushdie. Rushdie, who was marked for death by Islamic fundamentalists several years ago, was unable to travel because of the nationwide ground stop that halted commercial air traffic ordered by the Federal Aviation Administration.