omg-did you see this?

[filchthemildmanneredjanitor]

here?

This shit pisses me off. Here we are a really rich country and there are reports showing that the integrity of the bridge was questioned on at least two occasions during inspections. HOW COME NO ONE FIXED IT!

Good point, Leati. I get the impression public infrastructure is never the highest priority for US politicians, though. Not many votes lost in cutting corners until the bridge collapses/Hurricane Katrina overwhelms flood defences etc. etc. etc.

However, it is possibly just f*ck up rather than negligence. I used to work for a firm of civil/structural engineers. One of our senior guys inspected a car park. The owners only paid for a brief visual inspection and all seeemed fine. Unfortunately the next day the whole thing collapsed...

also remember the wobbly bridge? Designed and built at great expense by all manner of swanky architects and engineers none of whom appeared to have a clue it would be nigh on unusable...

Tis fixed now - but not very nice imho and contrary to the views of all those in the know. Looks like corrugated iron. Maybe nicer from the air when it looks like the famed "blade of light" but I don't tend to be up in the air so only see it from human height.

Ah, well, you see, margo, the wobby bridge was designed by Ove Arup IIRC. It was more an architect thing than an engineer thing. Engineers - good at making buildings stay up. Architects (and Ove Arup who are technically engineers) = good at coming up with exciting, visionary stuff that will probably have a few teething problems.

To be fair the wobbly bridge thing fell prey to human behaviour more than poor design.

Apparently no-one mentioned to the engineers that humans tend to fall into step when exposed to a regular rhythmic sound/movement. Which to be fair isn't really their domain.

Problem was that as the bridge moved slightly, people started walking at the same frequency as the bridge, which made the vibration stronger, which made more people walk in step... classic feedback loop. Killed off when they fitted whacking great dampers to soak up the vibration.

Two reports stated the bridge was "deficient." They just decided that despite the defiencies that the bridge would be okay.

apparatly, the architects behind the eye bridge at newcastle gateshead (Wilkinson Eyre?) were most put out when they saw the navigation markers under the bridge!!!! cos this stuff doesn't have to be functional now, does it!!

the bridge collapse is tragic. thoughts with those affected.

It was scheduled to be repaired in the year 2020. Apparently there are 80,000 other bridges that are deficient here in the US.

I'm on holiday in Minneapolis at the moment, and have watched the local news three times since last night and no one mentioned the report questioning the integrity of the bridge.

Oh Kevlar, that is no excuse, engineers should be well aware of the way people walk - Albert Bridge was built in Victorian times (obv.) and has a big sign telling soldiers to break step.

I remember learning in O-level Physics about soldiers needing to break step when crossing bridges, and about soldiers being used to test bridge designs by marching across in step. There was a famous bridge that disintegrated due to the wind through the valley blowing at its harmonic frequency. This is kindergarten stuff to bridge designers. No excuse for them not to know it.

But the Minneapolis bridge has been functioning for decades - surely the structural deficiencies are the sort that become apparent due to wear and tear, as well as perhaps not predicting the increased traffic flows over the years?

Othersideofthechannel,

Try CNN.

edam - totally agree. Engineers building a pedestrian bridge who don't understand how people walk should not be building a pedestrian bridge!

Ah, but Ove Arup are at the arty end of the profession, doing exciting creative stuff. So they say!