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Big Dig's legacy being undone by bolts

By Asociated Press
Published January 1, 2007

BOSTON - The legacy of the most expensive highway project in U.S. history is being defined not by the underground leaks that plagued it or the quintupling of its price to more than $14.6-billion.

No, it comes down to the hundreds of bolts, each weighing less than a pound, that were glued into the concrete tunnel roof to hold up the 4,600-pound concrete ceiling panels.

That's the focus of legal wrangling over the death of a woman killed when several panels collapsed one night.

A review of records and interviews with investigators by the Associated Press has found that:

-The bolts, about 5/8 of an inch in diameter and 6 to 8 inches long, according to various sources, had not been inspected since the tunnel opened to traffic in January 2003.

- Inspections after the July 11 accident showed many of the bolts had failed.

- Pressure to finish work while keeping costs low may have clouded contractors' judgment on which materials and methods to use.

Engineers who did not work on the project have criticized the use of bolts fastened with epoxy to secure heavy ceiling panels. "In my opinion, that is a big 'no,' " said Jai Kim, a civil engineering professor at Bucknell University.

Lee Mattis, principal engineer at CEL Consulting, a California firm that specializes in the design and testing of bolts used with epoxy, said they are usually used in sidewalks or walls. Crews rarely install them overhead, he said. "The installation presents some real problems because you are trying to force material up into a hole, and because of gravity, it wants to fall out," Mattis said.

Attorney General Tom Reilly said project manager Bechtel/Parsons Brinckerhoff knew when the tunnel was being built that there were problems with the bolt-and-epoxy system but used that design anyway. Five bolts that had been tested during construction came loose after a ceiling panel was suspended from them.

"The clock was ticking. The fuse was lit. It was just a matter of time until this tragedy occurred," Reilly said.

[Last modified January 1, 2007, 00:30:14]