Bridge failure during launch, Umeå, Sweden. 3

[RedSnake]

That bridge is actually less than 3 km from where I live.
The road they are building goes just outside the esidential area I live.
So every single day when I am taking my car somewhere, they have rerouted the road so it is never the same.

This was the launch plan.
The bridge steel construction is such that it must be delivered in smaller parts, 25 pieces with weights between 73 tons and up to 105 tons.
The parts are manufactured in a workshop and transported to the workplace first by barge and then by road.
When the parts arrive at the workplace, they are welded together on our launch plan and when necessarily many pieces are welded together, they are pushed out over the river, or in technical terms, launched out.
The launch is made with large jacks and we also have a type of brake fitted so that the launch can take place in a controlled manner.

"There were two braking devices fitted. - It is a wire brake with hydraulics and then a mechanical wedge that is mechanically driven in by hand but both failed"

This seems to be the king pin.

It also seems that they planned to move the bridge segment in steps of 3 dm at a time.

This happened in the morning so it may have been the first move of that day.
The temperature could have been as low +2 degrees in the night and when it happened around +8-10 mayby.
The sun comes up at 06.00 and the accident happened at 08.30.
My guess is they toke away the mechanical brake wedge away and the hydraulic brakes could not hold the weight for some reason..

And seriously guys..
It's called an erection for a reason. (it goes up !)
I've never heard a man say he got a launch !?!
It might come later though........
And you don't have to tell me, that I'm cheeky, I know I am ;-)

Best Regards A

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein

 

[RedSnake]

There is actually a film of the event when the bridge segment fell down that was taken by the main contactor.
They do not want to disclose it to the media, which I can understand.
Since a worker got hurt (my guess the one who was working with the brakes) the police is the first to be called on site.
The police will do a crime investigation on site because it is a work environment crime.
They probably took the film as evidence, wich means that the company can not release it, possibly they do not want to either.
But in this case, I think it depends on the first.
This as I understand it will not be investigated by SHK, but by the Swedish Work Environment Authority.
And probably by the Swedish Transport Administration.
The police have made a report regarding causing bodily injury through work environment crimes.
And one for causing danger to another wich is a civil case.
Probably because debris was falling in to the river, the worksite is off limits for anyone who do not work there, but downstreams this could have injured someone.

Best regards A

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein

 

[moon161]

Since a worker got hurt (my guess the one who was working with the brakes) the police is the first to be called on site.
The police will do a crime investigation on site because it is a work environment crime.

=8-0

I am stunned at the very concept of this. The police in the US are known to do quite a number of things, but this is not generally one of them.

 

[RedSnake]

Here in Sweden, the work environment law is a law with criminal penalties.
It can even mean imprisonment.

Work environment crime
When someone has breached their obligations under Chapter 3 of the Work Environment Act (AML) and it has led to a death, bodily injury, illness or causing danger to another, the person can be held liable for work environment offenses according to ch. Section 10 of the Criminal Code.
For the crime requires that you have intentionally or through negligence violated the work environment legislation.
There must also be a causal link between the breach of the requirements in health and safety legislation and the criminal effect of the breach (bodily injury, illness, etc.).

Of course, the police will not come if I cut my finger on a piece of metal.
It is the Swedish Work Environment Authority which informs the police whether it should be investigated by the police or not.
But it happends allmost everytime as soon as the ambulance or fire brigade is called, the police comes and secure evidence and interrogate.
It is then handed over to the prosecutor and then to the appropriate investigating authority.

Best Regard A


“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein

 

[moon161]

 

[IRstuff]

Nice!

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm

 

[moon161]

Forgive me. By way of analogy, there are many episodes of Star Trek where the some of the crew in the 'prime' universe encounter doppelgangers of their friends in an evil 'mirror' universe. In this respect I feel I have glimpsed the 'prime' universe of workplace safety.

 

[RedSnake]

But it works the other way too.
As an employee, you must follow the company's safety instructions and the machine manufacturer's user description.
Otherwise you can get fired (does not happen often) the most common reason for dismissal is probably theft or long-term illness where they can not find another job within the company.

It is forbidden by law to harm oneself at work in this country. LOL

This may be because it will be so expensive for society (the taxpayers) to take care of all the disabled if it were not so.
Since we all pay taxis to support people in diffuclt times.
Through early retirement or sick leave, which can be a consequence of such an event.
You get compensation from the state for the essentials, a roof over your head, food on the table, clothes, the most necessary needs met.
No luxury life compared to what you could have if you worked.

BR A



“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein

 

[RedSnake]

It is not often that someone ends up in prison in most cases there are fines that mostly goes to the state.
It never involves really large sums, everything is about making sure that it does not happen again, you can get orders to change things or routines, which is followed up by the authorities to see that it is complied with.
Compensation to the injured party comes via insurance policies taken out by the company or the trade union or the person himself.
They are intended to cover costs that are not covered by the state's social network, and you can receive lifelong compensation for reduced physical movement function, etc.

BTW I have a friend and he is a real a Star Trek nerd his role model is Jean-Luc Picard, he works at the Institute for Space Physics in Uppsala.
My other and oledst friend (We grow up in the same neighborhood, and I have known him since we were 6 years old, and we have been going to school together for more than 15 years)
I usually think of him as Spock they are very similar in looks and the way they think. LOL
He now works with software for security cameras.
Who I am I have not decided yet LOL

BR A

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein

 

[FacEngrPE]

It is possible, but quite unusual, in the US for OSHA to charge a person or company with criminal negligence. In states having harsher penalties than the Federal OSH law, referrals to state district attorney have occurred.

https://ohsonline.com/articles/2019/09/25/criminal-charges-for-osha-violations.aspx

Fred

 

[RedSnake]

First news of report from accident report.

In a consultant report, harsh criticism is now directed at the preparations for the half-finished Västra länken bridge to be laid across the Ume River.
Lower friction than expected and an undersized braking system must have caused the accident when the bridge beam slipped away.

It is the consulting company COWI that, on behalf of the Swedish Transport Administration, produced the report that explains how the accident in September last year could have occurred.
It was when the half-finished bridge was to be laid out over the river that it slipped away unchecked.
The bridge beam, which weighed about 1,800 tons, traveled 135 meters at a speed of up to 13 kilometers per hour. One person was injured in the shoulder at the time of the accident.

In the report's conclusions, COWI writes that the reason why the bridge beam began to slide uncontrollably was that the friction was lower than the contractor GRK expected.
And that when the beam picked up speed, there were no braking systems that could handle the situation.
"The brake system is not dimensioned to stop the bridge beam in uncontrolled sliding and consequently the brake system failed when it was hit," writes COWI.

Press conference this afternoon
Despite the risk of pushing the beam downhill, the contractor GRK has trusted that the friction would brake sufficiently instead of using some form of active braking system.
The amount of energy in the sloping bridge beam then created much greater forces than the existing braking systems could handle, the consulting firm states.

What is your responsibility as an entrepreneur for it going like this?

- We are responsible, but the report does not point out any individual.
This is a chain of events.
The report says that it was significantly lower friction than anyone could have assumed, says Magnus Ahlskog, who is site manager at GRK.

Could you have done something different?

- With the results in hand, we should have done it.
But I do not know what.
We thought it would go well, says Magnus Ahlskog.

Best Regards A

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein

 

[LittleInch]

"We thought it would go well" Haha - wonderful quote.

Any idea what they thought the friction would be versus what it turned out to be?? I suppose the report is wholly in Swedish... "significantly lower friction than anyone could have assumed"?? This sounds like a poor excuse to me.

As ever in these things, it really is a failure of the system to catch risks and issues where the checking and challenging of such procedures are inadequate or when issues raised are dismissed too easily.

At 1800 tonnes and going 3.5m/sec I bet they thought it was never going to stop....

Like it shows in this thread, the range of Friction coefficients is huge and this quote is pertinent.

https://www.eng-tips.com/viewthread.cfm?qid=479739

"Friction and friction coefficients are horribly undependable and fickle things. When you want and need them, you can’t count on them being there, because, for a dozen reasons they might not be there. "

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[RedSnake]

Well I will se what I can find out, it was on the news just an hour ago.
Just grabbed the first news article I could find, Swedish Television news..

We thought it would go well" Haha - wonderful quote.

I think it's a bit typically Swedish.
Not that we are worse at avoiding risks, but when things go wrong we don't have as much incitement to disclose it or the problem.

(Edit) I have asked for the complete report, but I do not no If they will give it to me, since it is not only the Swedish Transport Administration that ordered it but also an insurance company.

Best Regard A

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein

 

[RedSnake]

Damage investigation report is here.
It is in Swedish, I guess you can translate it, if needed.
If there is any specific details you wont to find I can help with that, but after working hours ;-)

"Damage investigation for bridge over Umeå river"

https://via.tt.se/data/attachments/00604/ba04e13c-5a52-407a-9d3b-77f0eafdbaf8.pdf

Best Regards A

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein

 

[RedSnake]

From report (chosen parts in descending order ) #1

The launch is carried out downhill, 2.25%, which means a risk with given uncertainties regarding the size of the coefficient of friction.
One span of 129 m to be launched, bronze weight including formwork is about 1800 tons and the drawstrings are long.
Accidents have happened in the past with this type of launch downhill.
Thus, this is according to ours meaning a known risk that should be analyzed in detail in advance.

Risk management is described in the assembly plan, where it is presented a general risk management plan.
The only point in the general risk management that manages risks with braking during launch refers to brake / rest wedges.
These wedges are basically a lock in a rest position but the comment states "Ensures that spare wedges are available and all participating parties are aware of directives for uncontrolled sliding ".
It can be realized that if the bridge is in motion is it is not possible to use the wedges for braking, which neither has has been the intention and there is also no general requirement in the Swedish Transport Administration regulations or in the tender documentation that a spare braking system shall be available.

The brake system is also not dimensioned to handle free sliding.
We have not found in the documents any directives or instructions for how the braking must be performed in detail.

However, the risk management plan for the cable systems in Chapter 5.2 mentions:

* ”uncontrollable sliding of the bridge section (downhill); Enough capacity of the break jacks, break jack strands will be kept a little bit loose but not too much ”

The assembly plan, chapter 3.6, launching bridge beams states that “The brake jacks are released as the main jacks pulls.
These are kept ready to prevent the bridge from starting to slide down freely ”.
Further in the assembly plan's chapter 6.1 control program is stated below monitoring of braking equipment that "Wires should be kept in tension.
Both the wires shall have the same tension +/- 50bar. "
Our overall interpretation of what is in the assembly plan about how jacks must be handled is that brake wires must be locked and with a some tension, but not too high tension and that one then gradually during traction lags behind with the brake jack.
However, this has not happened handling with brake jacks performed, without brake jacks have been unlocked with some slack in the brake cable before each new move.
However, the description of how to handle the braking system is unclear and there is no remark about how important it is that the bridge is not allowed to enter free sliding.

Best Regards A

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein

 

[RedSnake]

From report (chosen parts in descending order ) #2

The connection between the brake beam and the bridge beam was originally made of a screw connection.
At a later stage, this screw connection was changed to one connection with loop.

Experience from the first launch has been managed and this is documented in the minutes, the launch meeting 2020-08-14.
There you can read the following regarding the launch:
 “The bridge slipped / moved too far during one and the same rotation of the jacks, after the nasal fold had passed
stocks on Support 2 ”
 “the last shots were fired where the brake jacks were active during the launch shot.
Ie. with the brakes you could better control the progress of the bridge beam.

Tensile pressure was corresponding to 70-80 bar ”
It was thus already stated at the first launch that the bridge slid too far, free sliding and that an active braking was required.

BR A

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein