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  1. chris snyder

    Bridge Collapse in Genoa, Italy

    RandomTaskkk: "Cable snaps in one or other of the right hand stays (perhaps closest, hard to say?)" Yeah.. it happens so fast.. I can't single step the video, but kept clicking back to 00:37 from 00:38, and it looks like a truck/bus passes by the "closer" right side stay, then there's an almost...
  2. chris snyder

    Miami Pedestrian Bridge, Part VIII

    Unrelated to the FIU bridge, but compare the reactions and closures after finding a cracked beam in this SF structure to not even closing the road under the FIU span with MAJOR cracks. Another article said the total shutdown was "out of an abundance of caution" - caution was completely missing...
  3. chris snyder

    Miami Pedestrian Bridge, Part VIII

    Just saw this about OSHA fines. Still thinking how Navarro Brown wasn't hooked to safety harness, and the other worker hooked up when he heard/felt movement. I can't imagine people working up there with those big cracks at 11/12/deck without ensuring they were hooked up safely...
  4. chris snyder

    Miami Pedestrian Bridge, Part VIII

    I always thought that message from Pate was kind of goofy. When I first heard it, I thought it was from some burnout (forgive me for being judgemental) because there was no "drive" or authority to it like I'm used to hearing from senior engineers. I'm still not sure what to make of it...
  5. chris snyder

    Bridge Collapse in Genoa, Italy

    "Stays on the eastern span of the bridge had been remade, with huge costs," said Royer Carfagni, the Parma University lecturer, "But it was thought that the problem was not critical on the western span, which is the one that collapsed." Does anyone know why the east span stays were rebuilt, or...
  6. chris snyder

    Miami Pedestrian Bridge, Part VIII

    to TME: I just thought about WHO was supposed to inspect this bridge? When I put in underground electric service, the city inspector came out to make sure the trench was 18" deep, then did a final when completed... very simple job with two inspections. Assuming this bridge had a typical...
  7. chris snyder

    Bridge Collapse in Genoa, Italy

    This article talks about corruption in construction (almost halfway down). Has a lot of photos.. updated today with a lot of victims. "There were also concerns the Italian mafia could have contributed to the bridge's collapse by their construction companies being involved in maintenance work -...
  8. chris snyder

    Bridge Collapse in Genoa, Italy

    thebard3: "The link is Italian language for anyone who can read it" Attached is translation It may explain why the cables are flanked on the "concrete stays" of the NW tower. A different article said concrete stays are a unique feature, but I don't understand the point of doing it (so the...
  9. chris snyder

    Miami Pedestrian Bridge, Part VIII

    to RickyTickyTavi: First photos (~2/24/18, pre-move, after shoring removed, only supported at ends as in practice) showed a small diagonal crack on east side of #11 that continued north along the deck. In these photos, that crack expanded and #11 appears to have moved north about 1/2" - #12 was...
  10. chris snyder

    Miami Pedestrian Bridge, Part VIII

    Unreal. A clear indication to do some serious analysis of the forces at that connection. I wonder if #1-2 cracked at all.. they'd already tightened those rods and it held. Won't do it now, but will go back and see how this fits with GreenLama's theory - these cracks show initial step of...
  11. chris snyder

    Miami Pedestrian Bridge, Part VIII

    Good job - I wouldn't even know who to contact. This answers a question I had from the long, detailed article. The docs the engineers looked at are still available to the public.. when article said ~"docs not available except to those close to the investigation" it meant those that Miami...
  12. chris snyder

    Miami Pedestrian Bridge, Part VIII

    About documentation. This was the best/detailed article. http://www.staugustine.com/news/20180616/fiu-had-grand-plans-for-signature-bridge-but-design-had-key-mistake-experts-say It sounds like they made a basic public records request for the 2000 pages of calculations. "The Herald obtained...
  13. chris snyder

    Miami Pedestrian Bridge, Part VIII

    Tomkat: I can't answer your question about cold joint strength (details outside my field), but it's been discussed. I'd assumed #11/12 slid off the end of deck after breaking at cold joint, but recently someone posted a different view of #12's end that shows it broke below the cold joint...
  14. chris snyder

    Miami Pedestrian Bridge, Part VII

    I didn't know if this was typical, but noticed the small pieces, as if an "explosion" occurred... also small pieces in the rubble where #9 punched through the canopy. Still wondering why ~5 ft is missing from #11 with rebar/PT rod/duct and PVC pipes still intact. As discussed here, the...
  15. chris snyder

    Miami Pedestrian Bridge, Part VII

    One other thing (bugged me since someone asked "What happened to the cage?") - is this a welded or wired assembly, and is this the rebar MOJOJOHN said would shear when #11 moved north? Is hard to imagine the cage lifting or shearing without affecting the lower rod anchor (seems cage moving out...
  16. chris snyder

    Miami Pedestrian Bridge, Part VII

    Interesting video above. I saw a bit about the fall begin ~30:00, about #12 breaking from deck ~31:35, and more about the fall ~40:00. I didn't watch entire video, so missed explanation of exploding concrete. I may watch all later - the author brings up some good points but it takes time to get...
  17. chris snyder

    Miami Pedestrian Bridge, Part VII

    Rebar was running the length of #12 (spec of lower area above at 21 May 18 21:37) and likely held #12 together across the cold joint as (I suspect) #12 broke loose at the top of the upper anchor plate (in photo above at 21 May 18 18:40) along crack 6 where it meets crack 2 above (6 Jun 18...
  18. chris snyder

    Miami Pedestrian Bridge, Part VII

    TheGreenLama, I like the sequence - especially the crack pattern. Will think on it more. I must be wrong about #11 walking up #12 and going east... only 2 pieces of rebar on that side of #12 are slightly bent. I still wonder if the #11/12/deck joint (brittle concrete?) could literally...
  19. chris snyder

    Miami Pedestrian Bridge, Part VII

    Now I understand what you meant by ~"this wouldn't happen unless #11 got longer" #10/11 drops a bit just before collapse, which is why this man theorizes shearing at #11/12/deck wasn't the cause. He explains/stops it at 13:50. https://www.youtube.com/watch?v=RGfcJECoXXg I think I see the...
  20. chris snyder

    Miami Pedestrian Bridge, Part VII

    Miami-Herald is still pushing to get records released. Judge "Cooper refused to dismiss the case and instead gave federal investigators two weeks to decide whether they want to defend themselves in a Florida courtroom before he rules." Interesting that the author said cracks were noted "just...
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