US bridge collapse

Colour me fooled then.
So we can go back to speculation without you getting the arrse? Good.


Reviewing the following:

(Hopefully the link works, or the quote can be followed back to a link that does work.)

Initial failure seems to be in the location where the crane is, and there looks to be someone on the “roof” at the point of failure. Can’t see what goes first though.
I think the 'thing' on the roof is a human being. You can see someone falling on the video.

Considering the design has a single suspension tower which wasn't present, I'm wondering if the crane was used in place of it. A failure of the crane leading to a failure of the bridge? Speculation obviously.
 
They have just positioned a single span (6 lane motorway) bridge deck across the M27 using a powered ‘lift and drop’ mobile system. Months in preparation, less than a day in installation (36 hours early!) lets just hope that our systems are superior to the Septics... I travel under this about 6 times a week.

Highways chiefs praised as M27 reopens 36 hours ahead of schedule
 
Investigation of March 15, 2018 Pedestrian Bridge Collapse at Florida International University, Miami, FL

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

Some of the photos of cracks in that document are staggering.
I read the entire report. Fascinating. Everything that could go wrong went wrong.
  • The basic design of the bridge was bad and destined to failure.
  • The design didn't follow the original customer specifications requesting a steel bridge with redundancy built in.
  • The university approved the proposed design anyway because they liked the way it looked.
  • The engineering firm hired to review the design only looked at the final state and didn't look at what happened when they moved it in an intermediate state, as would normally be required by regulations. They did this because the design budget wasn't big enough to cover proper engineering of the intermediate stages.
  • When the bridge started cracking and falling apart the construction employees and inspectors reported there was a big problem but the engineers and project managers stuck their heads in the sand and tried to pretend it wasn't happening.
  • There were numerous points along the way at which the decision should have been made to close road and shore up the bridge before it collapsed. However the engineers and managers apparently didn't want to admit the seriousness of the problem and denied that the cracks were big and getting bigger despite the photographic evidence of growing cracks.
  • In an attempt to salvage the situation the bridge engineer specified that the tension on the steel rods be increased, but this had the effect of making the problem worse, causing the bridge to collapse, and resulting in the deaths of a number of innocent people.

Even if the bridge had been shored up before it collapsed it was probably not salvageable due to a fundamentally bad design. The best that could have been hoped for would have been to tear it down and write it off as a total loss. This may be why nobody with decision making power wanted to face up to the problem but instead seemed to just stumble along hoping for a miracle to occur.
 
I read the entire report. Fascinating. Everything that could go wrong went wrong.
  • The basic design of the bridge was bad and destined to failure.
  • The design didn't follow the original customer specifications requesting a steel bridge with redundancy built in.
  • The university approved the proposed design anyway because they liked the way it looked.
  • The engineering firm hired to review the design only looked at the final state and didn't look at what happened when they moved it in an intermediate state, as would normally be required by regulations. They did this because the design budget wasn't big enough to cover proper engineering of the intermediate stages.
  • When the bridge started cracking and falling apart the construction employees and inspectors reported there was a big problem but the engineers and project managers stuck their heads in the sand and tried to pretend it wasn't happening.
  • There were numerous points along the way at which the decision should have been made to close road and shore up the bridge before it collapsed. However the engineers and managers apparently didn't want to admit the seriousness of the problem and denied that the cracks were big and getting bigger despite the photographic evidence of growing cracks.
  • In an attempt to salvage the situation the bridge engineer specified that the tension on the steel rods be increased, but this had the effect of making the problem worse, causing the bridge to collapse, and resulting in the deaths of a number of innocent people.

Even if the bridge had been shored up before it collapsed it was probably not salvageable due to a fundamentally bad design. The best that could have been hoped for would have been to tear it down and write it off as a total loss. This may be why nobody with decision making power wanted to face up to the problem but instead seemed to just stumble along hoping for a miracle to occur.
If a Canadian P Eng had designed the bridge, or supervised its construction, this would not have happened.

I am not a Canadian P Eng, although I have worked with many of them as a peer. I hold myself to the same standard, because it's the best I have ever come across. I design fiber optic networks rather than bridges, so no direct physical harm will come of a failure of mine, but the consequential effects where the design includes hospitals, police, fire, ambulance infrastructure etc is not lost on me.

Iron Ring - Wikipedia

I just wish the same rigour was applied universally.
 
However I suspect the lecturers in the FIU Architecture and Engineering departments are rapidly scanning through whether they put their signatures to anything that was submitted for construction.....
I doubt if any of the engineering faculty submitted anything for construction. All US states have licensing for a variety of engineers (civil, structural, nuclear, electrical, bio-medical...) but there is no need for faculty to have professional licenses to teach, what they require is the academic credentials.

Anything submitted for construction requires plans signed and stamped by a licensed PE . Usually the engineer uses a thing like a notary seal to emboss his name, license and license number next to the signature.

A friend was, for many years, the director of a university's 6.6 megaWatt, HEU fueled, research reactor. He had a B.S., M.S. and D.Sci(Eng) from MIT. He also had all the appropriate licenses from the Nuclear Regulatory Commission After being in charge of the reactor for many years he decided to take the Nuclear Engineering exam in case he should change jobs and get work designing a reactor. He passed and can now add PE to the other letters after his name.

One nice thing about engineering is that you design things that last long after you are gone. Watching the horrible fire at Notre Dame I was amazed that the walls survived and still stand. Almost 900 years ago some brilliant French engineer designed the wonderful arcs-boutant that stabilized the walls.
 
If a Canadian P Eng had designed the bridge, or supervised its construction, this would not have happened.

I am not a Canadian P Eng, although I have worked with many of them as a peer. I hold myself to the same standard, because it's the best I have ever come across. I design fiber optic networks rather than bridges, so no direct physical harm will come of a failure of mine, but the consequential effects where the design includes hospitals, police, fire, ambulance infrastructure etc is not lost on me.

Iron Ring - Wikipedia

I just wish the same rigour was applied universally.
Pardon my ignorance, but what is a P Eng?
 
I read the entire report. Fascinating. Everything that could go wrong went wrong.
  • The basic design of the bridge was bad and destined to failure.
  • The design didn't follow the original customer specifications requesting a steel bridge with redundancy built in.
  • The university approved the proposed design anyway because they liked the way it looked.
  • The engineering firm hired to review the design only looked at the final state and didn't look at what happened when they moved it in an intermediate state, as would normally be required by regulations. They did this because the design budget wasn't big enough to cover proper engineering of the intermediate stages.
  • When the bridge started cracking and falling apart the construction employees and inspectors reported there was a big problem but the engineers and project managers stuck their heads in the sand and tried to pretend it wasn't happening.
  • There were numerous points along the way at which the decision should have been made to close road and shore up the bridge before it collapsed. However the engineers and managers apparently didn't want to admit the seriousness of the problem and denied that the cracks were big and getting bigger despite the photographic evidence of growing cracks.
  • In an attempt to salvage the situation the bridge engineer specified that the tension on the steel rods be increased, but this had the effect of making the problem worse, causing the bridge to collapse, and resulting in the deaths of a number of innocent people.

Even if the bridge had been shored up before it collapsed it was probably not salvageable due to a fundamentally bad design. The best that could have been hoped for would have been to tear it down and write it off as a total loss. This may be why nobody with decision making power wanted to face up to the problem but instead seemed to just stumble along hoping for a miracle to occur.
Yes, it's quite staggering how the cheese lined up at every opportunity. It would only have taken a simple decision to close the road as a precaution to have saved lives. That should have been taken by the people at the site, but it looks like there was a hierarchy in place and even when the engineer in charge saw the damage first hand he still didn't act.

There's a good chance of the "sunk cost fallacy" coming in to play as you suggest.

Individuals commit the sunk cost fallacy when they continue a behavior or endeavor as a result of previously invested resources (time, money or effort) (Arkes & Blumer, 1985). This fallacy, which is related to loss aversion and status quo bias, can also be viewed as bias resulting from an ongoing commitment.

For example, individuals sometimes order too much food and then over-eat just to “get their money’s worth”. Similarly, a person may have a $20 ticket to a concert and then drive for hours through a blizzard, just because she feels that she has to attend due to having made the initial investment. If the costs outweigh the benefits, the extra costs incurred (inconvenience, time or even money) are held in a different mental account than the one associated with the ticket transaction (Thaler, 1999).

Research suggests that rats, mice and humans are all sensitive to sunk costs after they have made the decision to pursue a reward (Sweis et al., 2018).
I don't know what the criminal charge would be in the US, but plenty of people were negligent to the point where criminal charges should occur.

I bet this fiasco will be taught in civil engineering classes as case on how not to do things.
 
I read the entire report. Fascinating. Everything that could go wrong went wrong.
  • The basic design of the bridge was bad and destined to failure.
  • The design didn't follow the original customer specifications requesting a steel bridge with redundancy built in.
  • The university approved the proposed design anyway because they liked the way it looked.
  • The engineering firm hired to review the design only looked at the final state and didn't look at what happened when they moved it in an intermediate state, as would normally be required by regulations. They did this because the design budget wasn't big enough to cover proper engineering of the intermediate stages.
  • When the bridge started cracking and falling apart the construction employees and inspectors reported there was a big problem but the engineers and project managers stuck their heads in the sand and tried to pretend it wasn't happening.
  • There were numerous points along the way at which the decision should have been made to close road and shore up the bridge before it collapsed. However the engineers and managers apparently didn't want to admit the seriousness of the problem and denied that the cracks were big and getting bigger despite the photographic evidence of growing cracks.
  • In an attempt to salvage the situation the bridge engineer specified that the tension on the steel rods be increased, but this had the effect of making the problem worse, causing the bridge to collapse, and resulting in the deaths of a number of innocent people.

Even if the bridge had been shored up before it collapsed it was probably not salvageable due to a fundamentally bad design. The best that could have been hoped for would have been to tear it down and write it off as a total loss. This may be why nobody with decision making power wanted to face up to the problem but instead seemed to just stumble along hoping for a miracle to occur.
Class action inbound I assume?
 
If a Canadian P Eng had designed the bridge, or supervised its construction, this would not have happened..
I don’t believe that is true. As a professional engineer (CEng & CPEng) I’ve worked with professional engineers in the UK, Australia, USA, Canada and Germany. I don’t believe there is much difference in quality or competence and certainly none in terms of ethics.

I read the report with deep professional interest; although I no longer practice. I think this was an accident waiting to happen in any developed jurisdiction. There simply aren’t enough competent engineers doing this stuff, so they don’t have enough time to be “professional”.

I could quote any number of Australian projects which have serious issues because properly qualified and experienced engineers were pushed to the periphery of the project.

WhtI left engineering? The commercial pressures to sign stuff off without the necessary time to make sure it was right.
 
P Eng == "Professional Engineer". You need to graduate from a recognised engineering school and work for a period of time doing related engineering work under the supervision of a suitably qualified person. After that you can write a set of exams to become a registered P Eng.

Being a P Eng is a necessary requirement to sign off on designs for many regulated fields, with civil engineering being one of the most common. Most engineers don't bother to get their P Eng as it has no relevance to the engineering they do, although many get it for the sake of prestige or because their company may pay a higher salary to those with a P Eng whether it is useful or not. The ceremony for induction into becoming a P Eng in Canada was written by Rudyard Kipling.

In Canada a P Eng will often wear a special iron ring. Legend has it that the ring was made from the iron of a bridge over the St Laurence that collapsed during construction over a century ago and that the ring is supposed to remind them of the need for humility. The bridge collapse led to much soul searching in the Canadian engineering profession at the time, although the bridge itself was designed by an American engineering firm with a prestigious record rather than Canadian engineers.
Here's an account of the Quebec Bridge collapse.
www.thecanadianencyclopedia.ca/en/article/quebec-bridge-disaster-feature
I suggest reading the following quote from the above linked article. If you read the recent engineering report regarding the bridge in Florida it will all sound eerily familiar.
The Quebec Bridge was to be one of the engineering wonders of the world. When completed it would be the largest structure of its kind and the longest bridge in the world, outstripping the famous Firth of Forth Bridge in Scotland. American engineer Theodore Cooper was chosen to design it. He was a proud even arrogant man who had numerous prestigious projects to his name, including the Second Avenue Bridge in New York.

Cooper chose the cantilever structure as the "best and cheapest plan" to span the broad St. Lawrence. That word "cheapest" would come back to haunt him. In order to cut the cost of building the piers farther out in the river, Cooper lengthened the bridge span from 490 metres to 550 metres. When Robert Douglas, a Canadian government engineer, reviewed Cooper's specifications, he criticized the very high stresses the longer span required. Cooper was outraged at the criticism by this nobody. "This puts me in the position of a subordinate," he raged, "which I cannot accept."

Cooper refused to supervise the construction on site, claiming ill health, and trusted Peter Szlapka, who was little more than a desk engineer. By the summer of 1907 the consequences of Cooper's design and of the lack of leadership on the site began to show up on the structure itself, especially in the "compression members" - the lower outside horizontal pieces running the length of the bridge.

A young engineer by the name of Norman McLure was the first to see the problem. On August 6 McLure reported to Cooper that the lower chords on the south arm were bent. Cooper wired back almost plaintively "How did that happen?" McLure reported two more bent chords on August 12 but Chief Engineer John Deans insisted that work continue. On August 27 McLure measured the bend again. The deflection had grown. He informed Cooper who wired the bridge company in Pennsylvania: "Place no more load on Quebec bridge until all facts considered." Cooper assumed that the work had stopped. Deans had read his wire but ignored it.
 
Not nearly as tragic, but non-the-less:

An University in Johannesburg during the apartheid era nneded a new building. As a working building, the university decided to use it as an education enhancer. Student architects designed the building, quantity surveyors costed it, building sciences did the interior (plumbing, electrickery) and ergonomics. The University faculties involved reviewed and rated the work. The city council then evaluated the building design for regulatory breaches and, finally, the actual building work was tendered out.

The single flaw in the design occurred when the builders wanted to get onto the first floor to start with the second floor walls... there was no stairwell between the three floors. To this day, there is an external staircase bolted onto the outside.
 

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