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I -40 Hernando Desoto Bridge at Memphis shutdown

Started by Wayward Memphian, May 11, 2021, 04:30:05 PM

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edwaleni

Quote from: kalvado on August 05, 2021, 03:27:35 PM
Quote from: edwaleni on August 05, 2021, 03:12:19 PM
Quote from: US71 on August 04, 2021, 08:28:47 PM
https://dailymemphian.com/section/business/article/23295/hernando-desoto-bridge-inspection-ardot

ARDOT officials have yet to explain how multiple inspections missed the potentially catastrophic crack that closed the bridge in May.

I thought they had a whole press conference on it. The guy said he inspected the bridge and signed the documents falsely and was fired.

What we haven't heard is the changes in the process ARDOT was taking on to protect against a repeat occurrence.
I wonder if that is available anywhere.
And if that is really the case, things should escalate quite a bit, as inspection report is submitted to FHWA, so feds could take an issue with overall situation.

The press conference said they were aligning their new bridge inspection process to the federal standards going forward. Ijust haven't seen what that entails.


Scott5114

This article suggests that the bridge inspector that was fired didn't see the crack because the typical inspection process involved viewing the cracked beam from underneath the bridge, an angle that a photo from the inspector's iPad showed the crack wasn't evident from.

https://arktimes.com/arkansas-blog/2021/07/21/one-cracked-bridge-one-person-fired-a-troubling-rush-to-judgment-raises-major-questions-about-bridge-inspections

Basically, ArDOT is looking for a scapegoat to cover up the fact that the standard procedure put in place by management couldn't have caught this crack.
uncontrollable freak sardine salad chef

kalvado

Quote from: Scott5114 on August 05, 2021, 03:58:31 PM
This article suggests that the bridge inspector that was fired didn't see the crack because the typical inspection process involved viewing the cracked beam from underneath the bridge, an angle that a photo from the inspector's iPad showed the crack wasn't evident from.

https://arktimes.com/arkansas-blog/2021/07/21/one-cracked-bridge-one-person-fired-a-troubling-rush-to-judgment-raises-major-questions-about-bridge-inspections

Basically, ArDOT is looking for a scapegoat to cover up the fact that the standard procedure put in place by management couldn't have caught this crack.
Scapegoa thing is pretty obvious. But inspector's explanation still incomplete.
They couldn't see the beam from the truck - well. maybe yes maybe not. beam was cracked on 3 sides, and inner face should be visible in the situation they are describing.
"went down every third cable"  - OK, again the same question: that is the work over the beam, looking at the crack...
Somewhat plausible explanation is that the crack lingered on one side for 6 years and then suddenly expanded. Not that I believe in that, but as a possible situation. Well, hopefully rust analysis will tell at least a part of the story.

bwana39

#328
Quote from: kalvado on August 05, 2021, 07:17:04 PM
Quote from: Scott5114 on August 05, 2021, 03:58:31 PM
This article suggests that the bridge inspector that was fired didn't see the crack because the typical inspection process involved viewing the cracked beam from underneath the bridge, an angle that a photo from the inspector's iPad showed the crack wasn't evident from.

https://arktimes.com/arkansas-blog/2021/07/21/one-cracked-bridge-one-person-fired-a-troubling-rush-to-judgment-raises-major-questions-about-bridge-inspections

Basically, ArDOT is looking for a scapegoat to cover up the fact that the standard procedure put in place by management couldn't have caught this crack.
Scapegoa thing is pretty obvious. But inspector's explanation still incomplete.
They couldn't see the beam from the truck - well. maybe yes maybe not. beam was cracked on 3 sides, and inner face should be visible in the situation they are describing.
"went down every third cable"  - OK, again the same question: that is the work over the beam, looking at the crack...
Somewhat plausible explanation is that the crack lingered on one side for 6 years and then suddenly expanded. Not that I believe in that, but as a possible situation. Well, hopefully rust analysis will tell at least a part of the story.

As I understand it the inspector believed the snooper type truck they had could not go to inspect the area where the crack was. That to deploy it there was contrary to the safety protocols for the vehicle. (I am not sure how or why, but it is what he said.) My initial thought was it was too wide or tall to go out that close to the pier (IE the shortest cable) and could not reach back from the next safe access opening. The hows are is just speculation on my part.

I never got the impression that the inspector ever said he falsely signed a document. He said that he didn't actually inspect this particular element closely. Then ARDOT extrapolated that he falsely signed the document because it said he had fully inspected the bridge.  As an aside, he was not qualified to be outside the traffic lanes except for in the inspection truck. He was not authorized to get onto the structure to inspect it.

The spot it was being inspected from was probably  too far away and likely gave a view angle that failed to make the damage visible. He probably inspected it exactly how he was shown how to do it by the previous inspector. He is not going to say anything. One would guess as long as he keeps from implicating others, he will likely be protected from prosecution. 

Like I said before, the word says the guy who spotted it was looking downward to make sure there was no marine traffic before he spit. Finding it was a bigger coincidence than missing it ever was.
Let's build what we need as economically as possible.

kalvado

Quote from: bwana39 on August 05, 2021, 11:22:22 PM
Quote from: kalvado on August 05, 2021, 07:17:04 PM
Quote from: Scott5114 on August 05, 2021, 03:58:31 PM
This article suggests that the bridge inspector that was fired didn't see the crack because the typical inspection process involved viewing the cracked beam from underneath the bridge, an angle that a photo from the inspector's iPad showed the crack wasn't evident from.

https://arktimes.com/arkansas-blog/2021/07/21/one-cracked-bridge-one-person-fired-a-troubling-rush-to-judgment-raises-major-questions-about-bridge-inspections

Basically, ArDOT is looking for a scapegoat to cover up the fact that the standard procedure put in place by management couldn't have caught this crack.
Scapegoa thing is pretty obvious. But inspector's explanation still incomplete.
They couldn't see the beam from the truck - well. maybe yes maybe not. beam was cracked on 3 sides, and inner face should be visible in the situation they are describing.
"went down every third cable"  - OK, again the same question: that is the work over the beam, looking at the crack...
Somewhat plausible explanation is that the crack lingered on one side for 6 years and then suddenly expanded. Not that I believe in that, but as a possible situation. Well, hopefully rust analysis will tell at least a part of the story.

As I understand it the inspector believed the snooper type truck they had could not go to inspect the area where the crack was. That to deploy it there was contrary to the safety protocols for the vehicle. (I am not sure how or why, but it is what he said.) My initial thought was it was too wide or tall to go out that close to the pier (IE the shortest cable) and could not reach back from the next safe access opening. The hows are is just speculation on my part.

I never got the impression that the inspector ever said he falsely signed a document. He said that he didn't actually inspect this particular element closely. Then ARDOT extrapolated that he falsely signed the document because it said he had fully inspected the bridge.  As an aside, he was not qualified to be outside the traffic lanes except for in the inspection truck. He was not authorized to get onto the structure to inspect it.

The spot it was being inspected from was probably  too far away and likely did give a view angle that failed to make the damage visible. He probably inspected it exactly how he was shown how to do it by the previous inspector. He is not going to say anything. One would guess as long as he keeps from implicating others, he will likely be protected from prosecution. 

Like I said before, the word says the guy who spotted it was looking downward to make sure there was no marine traffic before he spit. Finding it was a bigger coincidence than missing it ever was.
This is the illustration to the story - truck cannot extend an arm beyond being parallel to the bridge. I do buy that.
Now, although most images show a crack on the outside face of the beam, story is that beam is cracked on 3 faces. And even with arm motion restricted as shown, inner face is still visible from the bucket.

Rothman

Yeah, I find it hard to believe that someone bending over the railing to spit had a better view than an inspector in a bucket truck.

I have heard other horror stories about lackluster inspections (e.g., inspecting bearings on Hudson River crossing bridges with nothing more than a sledgehammer and spray paint), but none involved inspectors being unable to view elements of the bridge.
Please note: All comments here represent my own personal opinion and do not reflect the official position(s) of NYSDOT.

kalvado

Quote from: Rothman on August 06, 2021, 06:36:38 AM
Yeah, I find it hard to believe that someone bending over the railing to spit had a better view than an inspector in a bucket truck.

I have heard other horror stories about lackluster inspections (e.g., inspecting bearings on Hudson River crossing bridges with nothing more than a sledgehammer and spray paint), but none involved inspectors being unable to view elements of the bridge.
Going off-topic.. but how would you use spray paint in inspection? Crack penetration test?

edwaleni

Just my 2 cents. 

Perhaps they should train their inspectors on bridge dynamics to some degree.

Obviously no one with a mechanical or civil engineering degree wants to inspect bridges, but training the inspectors on where each bridge fluctuates through its cycles would be appropriate.

All bridges "breath" during their duty cycles and they breath during temperature changes. You would expect inspections to be looking at where those cycles create stress over time.

kalvado

Quote from: edwaleni on August 06, 2021, 11:40:01 AM
Just my 2 cents. 

Perhaps they should train their inspectors on bridge dynamics to some degree.

Obviously no one with a mechanical or civil engineering degree wants to inspect bridges, but training the inspectors on where each bridge fluctuates through its cycles would be appropriate.

All bridges "breath" during their duty cycles and they breath during temperature changes. You would expect inspections to be looking at where those cycles create stress over time.
And I don't think there was an actual expectation of crack in the problematic location. Moreover, looks like there is some lack of understanding of WHY that particular location failed.
Sp such training would be of limited, if any, help...

Wayward Memphian

My two cents is that this seems to align with the last major high water event an decade ago and two more in between then and now


Flood Categories (in feet)
Major Flood Stage:   46
Moderate Flood Stage:   40
Flood Stage:   34
Action Stage:   28
Low Stage (in feet):   5
Historic Crests
(1) 48.70 ft on 02/10/1937
(2) 48.03 ft on 05/10/2011
(3) 45.80 ft on 04/23/1927
(4) 41.37 ft on 03/04/2019 (P)
(5) 40.76 ft on 03/14/1997 (P)
(6) 40.50 ft on 02/22/1950
(7) 40.50 ft on 05/08/1973
(8) 40.32 ft on 03/07/1975
(9) 40.18 ft on 05/22/1961
(10) 39.59 ft on 01/08/2016

Rick Powell

Quote from: Wayward Memphian on August 10, 2021, 10:42:53 AM
My two cents is that this seems to align with the last major high water event an decade ago and two more in between then and now

Ordinarily, what happens down below with flood waters affects the bridge foundation more than the "superstructure" where the crack was found. And the Mississippi is considered to be a slow-moving river among the range of water crossings (typically, mountain streams are a lot more fast-flowing and can cause more damage in a shorter amount of time). Scour of the underlying foundation elements is usually the primary concern in flooding events.

edwaleni

Trains Magazine wrote a mocking paragraph on how it took so long to fix the DeSoto Bridge, when the Union Pacific was able to repair/replace a bridge due to a forest fire in a remote area in no less than 32 days.



"DOT does not stand for Done on Time"

Now compare UP's response to the sad case of the Hernando DeSoto Bridge, which carries Interstate 40 over the Mississippi River at Memphis. A May 11 inspection of the bridge revealed what inspections going back to 2016 had not: A large crack in the bottom of a critical steel support beam. The bridge was shut down immediately and officials from the Tennessee and Arkansas departments of transportation began drawing up repair plans.

Some 82 days later, the I-40 bridge was reopened to traffic – coincidentally on Aug. 1, the same day as UP's Dry Canyon Bridge. Yes, state highway crews and contractors took more than twice as long to make repairs that seem a lot less involved. (Don't take my word for it. See this Tennessee DOT video with oddly cheerful music.)

Rothman

Wonder what contract mechanism UP used to build the bridge.  They didn't use in-house crews, did they?
Please note: All comments here represent my own personal opinion and do not reflect the official position(s) of NYSDOT.

froggie

#338
One could argue there are vast differences between the UP bridge and the I-40 bridge.  First, I-40 had a nearby alternative route (congested as it is).  According to UP press releases, most of their train traffic had to reroute via Salt Lake City, several hundred miles away.  Second, the impact of the Dry Canyon Bridge to UP's operations was far more significant than the I-40 bridge loss was to Memphis and through traffic, so UP had a vested financial interest in repairing the bridge as soon as possible.

Regarding Rothman's comment, UP press releases suggest it was a mix of in-house and contractors who repaired the bridge.  I wouldn't call it a full replacement since about half the spans were repairable.


Decades ago, this sort of thing on I-40 WOULD have been handled by in-house DOT crews to repair highway bridges.  But the trend over the past few decades has moved away from in-house support and towards private consulting/construction firms.  I'm not certain that has been for the better.

armadillo speedbump

The Trains article was a stupid comparison of apples and oranges.  But given how often the author has poorly twisted his politics into his other articles, I'm not surprised.

bwana39

#340
Quote from: armadillo speedbump on August 12, 2021, 10:13:11 AM
The Trains article was a stupid comparison of apples and oranges.  But given how often the author has poorly twisted his politics into his other articles, I'm not surprised.

The apples were a for profit corporation. The oranges was multiple governmental agencies.  The fact is that the profit / loss motivation was far greater for UPRR than for the regional transportation grid. I agree had there been a total shutdown of traffic that the urgency might have been greater. That said, they didn't seem to piddle. They worked around the clock. The biggest delays were for the engineering and fabrication. After they got started it went seeming smoothly. UPRR did not have the engineering issues as they replicated the previous emplacement.

I think there is one issue worth noting: Micro engineering. I don't feel it came into play as much on the HDB as it does in routine road construction and maintenance.  I am not talking in the realm of mechanical engineering as much as the level of detailing in civil engineering. The railroads as a whole are just replicating the tried and true science proven through years of experience. In roadbuilding it seems to be all about re-inventing the wheel at each repetitive minute detail.  Over a hundred million dollars to engineer less than 20 miles of freeway in a mostly rural area. at Marshall tx.
Let's build what we need as economically as possible.

US71

Like Alice I Try To Believe Three Impossible Things Before Breakfast

kalvado


US71

Like Alice I Try To Believe Three Impossible Things Before Breakfast

armadillo speedbump

#344
Quote from: bwana39 on August 12, 2021, 11:48:45 AM
Quote from: armadillo speedbump on August 12, 2021, 10:13:11 AM
The Trains article was a stupid comparison of apples and oranges.  But given how often the author has poorly twisted his politics into his other articles, I'm not surprised.

The apples were a for profit corporation. The oranges was multiple governmental agencies.  The fact is that the profit / loss motivation was far greater for UPRR than for the regional transportation grid. I agree had there been a total shutdown of traffic that the urgency might have been greater. That said, they didn't seem to piddle. They worked around the clock. The biggest delays were for the engineering and fabrication. After they got started it went seeming smoothly. UPRR did not have the engineering issues as they replicated the previous emplacement.

I think there is one issue worth noting: Micro engineering. I don't feel it came into play as much on the HDB as it does in routine road construction and maintenance.  I am not talking in the realm of mechanical engineering as much as the level of detailing in civil engineering. The railroads as a whole are just replicating the tried and true science proven through years of experience. In roadbuilding it seems to be all about re-inventing the wheel at each repetitive minute detail.  Over a hundred million dollars to engineer less than 20 miles of freeway in a mostly rural area. at Marshall tx.

Um, no.  Those 2 bridges have completely different designs, which makes repair efforts completely different.  Same for completely different access and logistics for repair attempts.  You really don't see the massive difference in trying to repair a bridge spanning 3,800' of a deep river versus a relatively narrow mountain river? A massive arch that has to be repaired under load versus a relatively simple segmented trestle where they can lift each relatively short span on and off to replace is way too different for the author's comparison. 

It was a dumb apples to oranges comparison, even if the Mississippi River bridge had been privately owned and the California trestle gov't owned.  I agree there are key differences (advantages and disadvantages) to private vs govt, but the author was just going with a lazy cliche argument.

MikieTimT

Hopefully this one gets done thoroughly, and hopefully there's not major issues that need uncovering this time!

Routine Bridge Inspection of the Interstate 40 Mississippi River Bridge

bwana39

Quote from: MikieTimT on January 05, 2022, 05:14:22 PM
Hopefully this one gets done thoroughly, and hopefully there's not major issues that need uncovering this time!

Routine Bridge Inspection of the Interstate 40 Mississippi River Bridge

My thinking is this inspection will be anything other than ROUTINE.
Let's build what we need as economically as possible.

MikieTimT

Quote from: bwana39 on January 06, 2022, 07:22:30 AM
Quote from: MikieTimT on January 05, 2022, 05:14:22 PM
Hopefully this one gets done thoroughly, and hopefully there's not major issues that need uncovering this time!

Routine Bridge Inspection of the Interstate 40 Mississippi River Bridge

My thinking is this inspection will be anything other than ROUTINE.

I'd be interested to learn what they changed in their "routine" from the last time they did a "routine" inspection of the bridge.  There's a few more eyes on them this time around, so I'm sure there won't be missed fracture critical members going forward, at least for a while.  Seems like it'd be beneficial to use drones with appropriate imaging for the areas that the snoopers can't reach, or as a 2nd check of the areas that the snoopers can reach as a confirmation.

kalvado

Quote from: MikieTimT on January 06, 2022, 08:26:33 AM
Quote from: bwana39 on January 06, 2022, 07:22:30 AM
Quote from: MikieTimT on January 05, 2022, 05:14:22 PM
Hopefully this one gets done thoroughly, and hopefully there's not major issues that need uncovering this time!

Routine Bridge Inspection of the Interstate 40 Mississippi River Bridge

My thinking is this inspection will be anything other than ROUTINE.

I'd be interested to learn what they changed in their "routine" from the last time they did a "routine" inspection of the bridge.  There's a few more eyes on them this time around, so I'm sure there won't be missed fracture critical members going forward, at least for a while.  Seems like it'd be beneficial to use drones with appropriate imaging for the areas that the snoopers can't reach, or as a 2nd check of the areas that the snoopers can reach as a confirmation.
Rules say everything must be inspected by direct eye sight. Drone is not an acceptable alternative.
I am not sure if that is a good or bad thing. 

MikieTimT

Quote from: kalvado on January 06, 2022, 08:33:55 AM
Quote from: MikieTimT on January 06, 2022, 08:26:33 AM
Quote from: bwana39 on January 06, 2022, 07:22:30 AM
Quote from: MikieTimT on January 05, 2022, 05:14:22 PM
Hopefully this one gets done thoroughly, and hopefully there's not major issues that need uncovering this time!

Routine Bridge Inspection of the Interstate 40 Mississippi River Bridge

My thinking is this inspection will be anything other than ROUTINE.

I'd be interested to learn what they changed in their "routine" from the last time they did a "routine" inspection of the bridge.  There's a few more eyes on them this time around, so I'm sure there won't be missed fracture critical members going forward, at least for a while.  Seems like it'd be beneficial to use drones with appropriate imaging for the areas that the snoopers can't reach, or as a 2nd check of the areas that the snoopers can reach as a confirmation.
Rules say everything must be inspected by direct eye sight. Drone is not an acceptable alternative.
I am not sure if that is a good or bad thing.

They'd have to use something other than snooper trucks to get eyes on the areas like this fracture were as there are limitations to where the booms can swing.  So, hopefully, they've gotten more ways to get inspectors over the edge to get eyes on.  I'm sure they have made quite a few changes as a result of the proctological assessment they underwent that culminated in the Nov. 9 final report of the incident.  I know they've got to start using consultants on inspecting the Hopper Tunnel as they had the bridge inspection department inspecting that too, even though they lacked the appropriate electrical and mechanical engineering expertise to actually adequately do the job according to the final report.



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