Thursday, August 02, 2007

Bridge Disaster

This horrific tragedy is going to attract the opinions of every engineer, would-be engineer, failed engineer, and random pundit. Okay, so I am one, too.

For I don't honestly know if this is an important observation, but check out this detail of satellite-recorded imagery from 1991, over Minneapolis:

This could be an artifact of splicing together a zillion photos taken from afar, but look at that loopy edge to the fated 35W Interstate bridge? I mean, the Cedar Street Bridge is right next to it, and it's straight as an uncooked noodle. Is anyone out there able to shed some light on this oddity?

I can't help but feel that this is some clue to the demise of the bridge. I saw the spot on CNN where, in 2001 or 2, one engineer's report on the bridge's structural system pointed out some sort of flaws. Here it is:
For the state transportation department, the University of Minnesota Civil Engineering Department reported that there were preliminary signs of fatigue on the steel truss section under the roadway, but no cracking. It said there was no need for the transportation department to replace the bridge because of fatigue cracking. But CNN did elaborate with the findings: the structure itself did not have a secondary support system should one level of support fail. In other words, the design of the bridge could have been augmented with supplementary, or secondary, support, just as insurance.

But I am no engineer, just an internet addict who should be working on that novel rewrite.

I can't access google maps from here for some reason. I would like to be able to compare their images with the TerraServer, above. I mean, maybe the site is jammed up from too many people trying to view the scene of the disaster, but for now I cannot get to that image from Bali.

Thanks, , for the posting of this and other images.

No comments: