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‘Significant overload’ caused Norway’s timber bridge collapse

newcivilengineer.com

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Re: ‘Significant overload’ caused Norway’s timber bridge collapse

#3

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I used to enjoy a game called game developer simulator and I do wonder if modern day software development coukd start there instead of with a committee of diluted opinions tied to a budget irrelevant to the budget of software developer beyond a career or two

In a sense star citizen may be the best managed game of all time

Sometimes I wonder how experts in a technical field play a mobile bridge building game with toy physics and somehow believe themselves to be in position to replace actual experts in building bridges who actually are legally responsible for the outcomes of their work in a way the overwhelming majority of software devs won't ever face.

Maybe just leave the mobile game for fun and take up a few classes in structural analysis, steel design, concrete design, wood design, highway geometric design, actual bridge design, and capital planning. Then when you have the same experience as the smallest baby bridge designers (because that's just the starting point - classes) see if your bridge game encompasses the risks and realities of designing and building a bridge.

You ever had to do first nations consultation in your bridge game? Ever needed environmental approval in there? What sort of k factors your road curves have ever get checked against the code? Do horizontal and vertical alignment? Design a foundation that has to live as long as you or more? Do a flood analysis, or ice jam analysis, fish passage analysis or a million other things that could affect the hydrology of a watercourse under a bridges? Ever had a software project delayed because an endangered species of bird was nesting in your software and you legally couldn't remove it? How much time did you spend designing the asphalt mix for the road surface in your bridge game?

Stick with software and your mobile game.

Re: ‘Significant overload’ caused Norway’s timber bridge collapse

#4
The homepage of the "Norwegian Safety Investigation Authority" is much more informative and the 2 documents have interesting photos, e.g. closeups of where the wood broke.

https://www.nsia.no/Road/Investigations/22-441

It does not state why they conclude the cause was overload, only that "Uncovering the technical causal factors for the collapse of the Tretten bridge has been challenging. The expert group has worked its way through several hypotheses to be able to exclude non-relevant fracture mechanisms, by connecting findings to computational analyses. There was significant consequential damage to the bridge structure, both from the collapse itself, the impact with the ground and the salvage work, and it has been challenging to separate these from each other."

Personally I would think that a bridge should be able to handle "A passenger car and a truck with trailer loaded with lime were on the bridge when it collapsed".

Re: ‘Significant overload’ caused Norway’s timber bridge collapse

#5

The homepage of the "Norwegian Safety Investigation Authority" is much more informative and the 2 documents have interesting photos, e.g. closeups of where the wood broke. https://www.nsia.no/Road/Investigations/22-441 It does not state why they conclude the cause was overload, only that "Uncovering the technical causal factors for the collapse of the Tretten bridge has been challenging. The expert group has worked i…

There are a number of bridges where I live that cannot handle a truck with trailer. They have large signs warning what the maximum load is.

They are mostly on rarely used roads in farm country (as in a handful of cars per week cross), so a truck with lime is one of the more likely potential loads, but of course the local farmers know that bridge can't handle the weight of a truck and plan their deliveries to take a different route (which often more than doubles the trip time vs if the bridge could handle the weight)

Re: ‘Significant overload’ caused Norway’s timber bridge collapse

#6

The homepage of the "Norwegian Safety Investigation Authority" is much more informative and the 2 documents have interesting photos, e.g. closeups of where the wood broke. https://www.nsia.no/Road/Investigations/22-441 It does not state why they conclude the cause was overload, only that "Uncovering the technical causal factors for the collapse of the Tretten bridge has been challenging. The expert group has worked i…

I think they mean that this particular element was massively overloaded (200% more than its max, which would mean 400% of the design load), not that a few cars and a truck were overloading the bridge. It was more the structure self weight that is relevant. Somehow extra load was transferred onto that element which should have been taken by other elements. It doesn't seem good that failure of one element would cause the whole thing to fall down though.

Re: ‘Significant overload’ caused Norway’s timber bridge collapse

#7
post #5

The homepage of the "Norwegian Safety Investigation Authority" is much more informative and the 2 documents have interesting photos, e.g. closeups of where the wood broke. https://www.nsia.no/Road/Investigations/22-441 It does not state why they conclude the cause was overload, only that "Uncovering the technical causal factors for the collapse of the Tretten bridge has been challenging. The expert group has worked i…

There are a number of bridges where I live that cannot handle a truck with trailer. They have large signs warning what the maximum load is. They are mostly on rarely used roads in farm country (as in a handful of cars per week cross), so a truck with lime is one of the more likely potential loads, but of course the local farmers know that bridge can't handle the weight of a truck and plan their deliveries to take a d…

The problem comes when those type of bridges don't collapse the first time someone overloads them; then people start using it because "eh it works" and eventually it fails.

Re: ‘Significant overload’ caused Norway’s timber bridge collapse

#9

The homepage of the "Norwegian Safety Investigation Authority" is much more informative and the 2 documents have interesting photos, e.g. closeups of where the wood broke. https://www.nsia.no/Road/Investigations/22-441 It does not state why they conclude the cause was overload, only that "Uncovering the technical causal factors for the collapse of the Tretten bridge has been challenging. The expert group has worked i…

I read it to imply there was a design or construction problem that meant the part that failed experienced much more load than intended.
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