Pontiac Silverdome partial implosion today!

[JBMcB]

My wife took the kids. The viewing lot was packed. The inner ring was supposed to come down [[the bit that held up the roof) but it didn't. I could hear the explosion from 6 miles away, and it was loud from here.

I've seen shows about imploding buildings - when this happens they generally leave the structure alone for a day before checking out what happened. Sometimes it only takes a few more small charges, or they'll tie the supports to a few bulldozers [[with a LONG cable) and pull it the rest of the way down.

It's not uncommon. The demolition guys work off of whatever blueprints are available, which might not include on-site changes made for some reason or another. The blueprints say you need at least X grade concrete for the supports, but you can only get Y grade concrete, so you use Y grade concrete. Now the supports are 20% stronger.