Interesting Bay Bridge Failure Article

Looks like the cross-sectional-area of the tie rods was far too small to act as a replacement of the cracked eye bar (whatever the alloy and heat treating of the tie rods). Once one tie rod fails, the other one on that side fails immediately and the whole lot gets catapulted away.

OTOH, I'm an electrical engineer by training ant a computer herder by trade...

Mark Rand

Interesting pictures. The crack probably grew slowly over the course of years, as a result of fatigue and corrosion. It's unlikely that it appeared suddenly.

The temporary repair probably failed because it wasn't very carefully designed in comparison to the bridge.

It's a testament to the design of the bridge that it's still standing with a failed eyebar. Other eyebar bridge designs have collapsed when a single bar fails:

Chris

They had a satellite channel program on how that bridge fell, and when I saw "eye-bar" and "Bay Bridge" it caught my interest immediately. But they were different designs, although they used the one common element. No single point of failure on the Bay bridge, even though one roadway panel did fall in the '89 quake, the whole thing stayed up. And I can see what they were trying do do with that patch, but it looks like somebody didn't do the sums. Just trying to patch things to make it last until the new span is ready(might be awhile given the economic climate out there).

Stan

Thanks for sending the link. Very interesting. My Dad and an Uncle were California State Division of Highways, District Engineers in opposite ends of the state. Both dont understand why the crack, which is old enough to have rusted, was not detected during inspection. They looked at the site and pictures and said that someone should have caught it much earlier.

Where the hell were the overpaid painters? A crack that big, had to be there longer than a paint cycle.

Because it will be taken down they have stopped painting it.

CP