Tuesday, July 10, 2007

Bad glue

From the Boston Globe: "Fast-drying epoxy used in Big Dig let bolts slip over time"

Investigators for the National Transportation Safety Board said today that part of a Big Dig tunnel collapsed a year ago because the wrong epoxy was used to secure the ceiling, allowing bolts to slip or "creep" over time.
Honestly, I can't see the justification to using epoxy at all. If you're going to hold up heavy tiles, a bolt is better (risk of shear) but a cross-connection is best (risk of fracture). But epoxy? You're just crossing your fingers it doesn't deteriorate over time.

2 comments:

Anonymous said...

And the panels could have been much lighter. My understanding is that they were strictly cosmetic (not structural).

Anonymous said...

They realy should have used CRAZY GLUE or GORILLA GLUE