Miami Pedestrian Bridge, Part IX 33

[JAE]

A continuation of our discussion of this failure. Best to read the other threads first to avoid rehashing things already discussed.

Part I
thread815-436595

Part II
thread815-436699

Part III
thread815-436802

Part IV
thread815-436924

Part V
thread815-437029

Part VI
thread815-438451

Part VII
thread815-438966

Part VIII
thread815-440072


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[MikeW7]

"Gator ate it...."

 

[TheGreenLama]

Louis Berger, will we ever see what your superstructure review consisted of?

 

[jrs_87]

Has everyone here seen this?

https://www.youtube.com/watch?v=GMyvLeNOPOw

 

[3DDave]

I think many here know about his invention and many successful cable stayed bridges. It's why many are puzzled that he was working on a post-tension concrete structure. It doesn't solve the question about why people familiar with post tensioned concrete were climbing onto a bridge that was spalling off 100 pound chunks from the most heavily loaded portion, especially when they knew the FIGG hadn't done any like that before.

 

[jrs_87]

3DDave 10 Jun 19 21:39

Not trying to be facetious here; my wife thinks they were hypnotized.

 

[gwideman]

I originally created this image at an early stage in this thread, and not knowing the dimensions, I drew the wireframe outlines of #11 and #12 far too wide. Their width should not encompass the two pairs of white vertical pipes/sleeves, a detail which is rather critical. (I realize this wasn't the main point of jrs_87's post, I just don't want to perpetuate an incorrect impression about this crucial area.)

A much better version of this idea was posted by

24 Mar 18 23:47

 

[thebard3]

.

https://www.nbcmiami.com/investigations/Judge-Dema...

Wow. This thing has really turned into a mess. It sounds like Figg is ready to file for bankruptcy, which might have limited their liability a little bit, unless they destroyed and altered evidence like the article suggests. Also, I think the first video clip is kind of hilarious, with FIU seeming to think that they can escape all future lawsuits by relinquishing a $5M claim against MCM. I'm sure they would love to get off that easy.

Brad Waybright

It's all okay as long as it's okay.

 

[jrs_87]

Things are heating up:

https://www.miamiherald.com/news/local/community/miami-dade/article231428938.html

Note: At time of this post, article is being updated constantly by the Herald, is incomplete, and is poorly written.

 

[Vance Wiley]

Time required to install shoring ?
Does anyone have an idea of the time required to mobilize the transporters and get them under the structure so they could have prevented this collapse?
Where are they stationed - how fast can they travel, what set-up time is required - could they just have been driven back in a short time?
This might tell us when it became too late to do anything that would have saved the structure. Of course, there is the question of repairs - if one does not know why it is cracking, they do not know how to fix it.

 

[JStephen]

Step 1 would have been to stop traffic under it, whether they could shore it up in time or not. And that could have been done in about 5 minutes.

 

[MikeW7]

Does anyone have an idea of the time required to mobilize the transporters and get them under the structure

The SPMT's are assembled like an erector set from a bunch of smaller parts that each fit on a semi-sized flatbed. I reviewed the SW timelapse (Bridge-PG6-Mar 1-19-2018-1080.mp4) and it appears the first parts arrived on the 1st and they started the move the evening of the 9th. Most of the last two days were spent installing chains, instrumentation, etc. The move was completed the afternoon of the 10th, and the SPMTs were parked until the next day (11th) when the disassembly started. The very last load left the construction site a few hours before the collapse on the 15th.

 

[MikeW7]

I'm in the process of created videos for the multi-hour inspections that took place on the 13th and 14th. It wasn't just a case of a few people taking pictures for an hour or so - there were several crews at various times inspecting the deck (mostly at column 11-12 junction ), the underside of north pier-deck interface (by manlift), and walking on top of the north pier.

 

[Vance Wiley]

MikeW7 - Thanks.
That means basically a week to get shoring under the bridge - that is about the length of time the thing had sat unshored. The outcome was determined the minute it was set on the piers.
The progressive nature of the cracking developed over at least 2 days - maybe more. No crack monitoring established - no visual recognition of a failure in progress. And they all sat silent in the meeting.
Has NASA verified the existence of Black Holes of Intelligence? I'm thinking one developed at the March 15 meeting site.
I'll bet an attorney can find that they exist.

 

[Vance Wiley]

JStephen Step One - how true. And saved 6 lives and what - 12 injuries? And $42 million to date.

 

[MikeW7]

Vance Wiley - Kevin Hanson took his crack pictures within a few hours of the bridge being installed - you can watch his crew on top of the canopy in the Move 4 videos that started just as the SPMTs were removed: North view - SW view. My guess is that Hanson is the guy in the lime green shirt roaming the deck - the same shirt was observed on the guy wandering the deck on day of the collapse, and Hanson had to be dug out of rubble after the collapse, so he was probably the deck guy.

The reports coming out now said that Hanson was agitated/alarmed when he called his boss because of the gaping cracks that developed immediately when the rods were untensioned. The pictures he took (and sent to his boss) have never been released - court fight going on but last I heard a judge wants them released and added to the public record. In a story earlier this year his girlfriend said she didn't want him to go back on the bridge (he had to return the morning of the 14th - day before the collapse), I guess because of what he told her.

In the videos I've reviewed so far I didn't see anybody return to the bridge later that afternoon of the 10th or the next day (11th) but somebody was on the deck for a few frames on the 12th (in N view only - haven't looked at SW view yet). On the 13th and 14th there were crews on the deck on and off most of the day - will have videos up tonight, I hope.

 

[gwideman]

posts videos

That's some informative work you're doing. Any chance of adding some kind of date (or even better, date-time) overlay? That way we viewers could easily see how the inspections corresponded to other events in that critical week.

Also, you mentioned Hanson reporting cracks that developed immediately on untensioning. Do you have a source for that? Thanks.

 

[MikeW7]

Any chance of adding some kind of date (or even better, date-time) overlay?
...
Also, you mentioned Hanson reporting cracks that developed immediately on untensioning. Do you have a source for that? Thanks.

Tonight I plan on renaming videos so they start with Date, and in the video description I will add a time stamp at the end of the original video name, something like: video_name.mp4 starting at hhh.mmm.ss

I really have no way of adding a real-time time stamp to the video because they don't have an embedded clock.

FIU bridge worker took pictures of cracks before collapse | Miami Herald

 

[jrs_87]

‘It cracked like hell.’ Feds say engineers didn’t heed alarms before FIU bridge collapse

The Herald has re-written article:

https://www.miamiherald.com/news/local/community/miami-dade/article231428938.html

 

[gwideman]

FIU bridge worker took pictures of cracks before collapse | Miami Herald

Thanks MikeW7. But...

"When Kevin Hanson noticed that the thin cracks veining a crucial connection in the Florida International University bridge had opened into gaping fissures, he pulled out his phone and snapped a few photographs. It was March 10, 2018, the day the prefabricated bridge had been raised over a busy commuter road."

So far as I noticed, that article does not say that Hanson's pics were taken immediately after untensioning specifically. It might well be the case, and seems plausible, just doesn't seem explicit in this article.

 

[jrs_87]

OSHA report released today (115 pages):

https://www.osha.gov/doc/engineering/pdf/2019_r_03.pdf

The amount of detail is extreme and perhaps not typical for OSHA.