'Epoxy creep' factor in Big Dig deathBy Andrew Miga, Associated Press Writer | July 10, 2007
WASHINGTON --A materials failure called "epoxy creep"
was a major factor in the Big Dig highway tunnel ceiling
panel collapse that killed a woman a year ago, federal
investigators said Tuesday.
The accident could have been avoided if any of the
agencies involved in the tunnels' construction and
design had considered the possibility of epoxy slowly
pulling away from the tunnel roof, investigators with
the National Transportation Safety Board said.
Milena Del Valle, 39, was crushed to death on July 10,
2006, when 12 tons of concrete ceiling panels fell from
the roof of the Interstate 90 connector tunnel as she
and her husband drove toward Logan Airport. The panels
had been fasted to the concrete tunnel roof with bolts
anchored in epoxy.
Bruce Magladry, director of the NTSB's Office of Highway
Safety, described "epoxy creep" as the tendency of some
epoxies to slowly give way under constant pressure.
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