Natrix, you have any input on this little old bridge that got shoved over the m1 a few months back?

Nothing to do with me, looks impressive though.

Am I right in thinking that much of the bridge strengthening and concrete barriers we have had added to our network is to do with the rise in Weight of the hgv’s throughout Europe?

Most of the strengthening has certainly arisen from the increased hgv weights.

From that before/after picture, that long deck looks incredibly badly supported and stayed.

“Nothing to do with me, looks impressive though”

Standing on an 8 lane closed section of the m1 was a very weird feeling, one of those where you wished you had a supercar available for a quick blast in.

Going back to the Genoa bridge, there’s already some nasty talk coming from government sources basically slating the operating company, with one stating it as being the most expensive privately run toll roads in Europe with little of that revenue being spent on maintenance.

Tbere must be some very nervous management sitting round at the moment and rightly so.

Their ‘enemy’ is mainly government, who don’t have the budgets to build this level of resilience and so when they see the cost of building the proper solution then start cutting corners to hit a price point.

The ‘enemy’ is very much the people who vote for those governments. We can’t blame a government for ‘not having the budget’ when they stand for election on the promise that they won’t have the budget.

From that before/after picture, that long deck looks incredibly badly supported and stayed.

Do you mean the bit between the cable stayed sections? Looks OK to me.

nasty talk coming from government sources basically slating the operating company

Isn’t this the tack of the right wing/populist PM wanting a hate/blame figure for the plebs to focus on?

There has just been an Italian chap on 5LIVE who recently prepared a report on this bridge and others similar. He said that with the benefit of 50 odd years of hindsight that the design was flawed. The concrete in places was in tension rather than compression.

Am I right in thinking that much of the bridge strengthening and concrete barriers we have had added to our network is to do with the rise in Weight of the hgv’s

Bridge strengthening partly HGV and partly just many more vehicles overall. Concrete barriers more a change in society’s risk appetite.

The concrete in places was in tension rather than compression.

Pre-stressing compresses the concrete so it can take tensile forces. Not saying the bridge wasn’t badly designed, but it did stand for 50 years so I expect the designer understood the basic concepts of structures and stress.

He compressed an extensive study into a 90 second soundbite and basically said that with the benefit of hindsight they wouldn’t do it that way now. I guess that over time the material has degraded and the loads have increased/fatigued it.

Like you said, it had stood for 50 years… until yesterday.

Carbonation front issues?

The ‘enemy’ is very much the people who vote for those governments. We can’t blame a government for ‘not having the budget’ when they stand for election on the promise that they won’t have the budget.

Very true – and in the end, we have to fund these via taxation, etc. so finally we get what we are prepared to pay for

(not saying this is the case here, with allegations of scrimping on costs within the budgetary framework, etc.)

Can’t help thinking that the projected spend on HS2 might be better used maintaining and enhancing our existing transport infrastructure.

Carbonation front issues?

Or carbonara issues?

If corrosion was a factor more likely to be chloride induced as Genoa is on the coast, but that is still wild speculation……

The ‘enemy’ is very much the people who vote for those governments

Erm…or the press who support (lie for) the winning side, or the winning side who sells itself (lies) the best?

The concrete in places was in tension rather than compression.

The underside of any load bearing beam will be in tension. That’s why there is reinforcing steel – THAT is in tension. There is a “limit state of design” for cracking in addition to that for strength (well in the UK there is) which ensures there is limited cracking in the concrete where it is in tension, mostly to prevent ingress of water but also to prevent public alarm  – “aagh look its cracking it’s going to fall down”.

Just going off what the guy who wrote the report on the bridge said.

The implication was that they wouldn’t use concrete in the same way on a modern bridge. I don’t know whether he was referring to the deck, the tower, the structure between the deck and tower or something entirely different.

I suspect that one conclusion will be is that privatising the safety-critical aspects of public infrastructure is a dangerous activity in a similar way to the issues emerging from Grenfell.  Contractor bids on the basis of a set-number of hours / estimate / wet-finger for the amount of hours of inspections / remediations to be undertaken within a given period of time and simply bills for those hours – job done. By the time work has been sub-contracted out a few times, no-one will have any responsibility for the structural integrity of the bridge. The defence will be that they inspected the bridge regularly and brought to the attention of the public body anything they found, but the public body will say they didn’t have enough money to do the work / were trying to negotiate an ‘affordable’ solution. Nimrod crash XV230 is another case in point.

An article that came up today

Most of the UK infrastructure was built by the Victorians. Sorted. Built to last but not for modern life.

RIP for those that died – this should never happen in any country, never mind Europe.

I’m going to relish going over the QE2 bridge next week. Gives me the shivers at the best of times…. not right keen on bridges me.

Most of the UK infrastructure was built by the Victorians. Sorted. Built to last but not for modern life.

https://en.m.wikipedia.org/wiki/Great_Sheffield_Flood

https://en.m.wikipedia.org/wiki/Tay_Bridge_disaster

Ever since bridges some have been built they have collapsed, due to weather , poor building or overloading etc, its just a fact of life, engineers can test them and design them to withstand terrific forces, but its the abnormal that makes them usually fail.

Sadly a lot of people lost their lives, due to some fault, we as yet dont know of.

I’m going to relish going over the QE2 bridge next week. Gives me the shivers at the best of times…. not right keen on bridges me.

From what I’ve read, the actual design of that bridge was flawed, throwing money at it year on year trying to maintain the structural integrity of something which didn’t have much structural integrity in the first place was a foolish waste of time and money. All bridges need constant maintenance, especially when crossing water, but if the fundamental structure is sound, then the bridge should last for decades without issue. The first Severn Bridge, built in the 60’s is a good example, the actual deck was a completely new concept, and was only adopted after a delay finalising the original design, but set the standard for modern suspension bridges worldwide. Fascinating programme about it on telly recently, my dad took me down to Aust to see it while it was being built, and it’s great to walk and cycle across, a beautiful structure.

RIP to the victims of the collapse.

That was a damn long way to fall.

My family and I drove over it last week on our way back from holidays. It sent a proper shiver down my spine when I realised it was the bridge we drove over. There was a lot of work going on it at the time.

Here’s a quote from an article in New Scientist I’ve just read:

During a recent project on the Hammersmith Flyover, a bridge in London, they attached acoustic sensors to the bridge that heard when strands from the steel cable broke.

“Normally this happens so rarely you can’t be sure if your sensor is working, but with Hammersmith they kept pinging a lot,” says Jackon. This meant that extra steel cables had to be retrofitted to the exterior resulting in a lengthy and costly repair job.

Around Europe many bridges are in a poor state. A report in France from earlier in the year said that a third of the country’s road bridges are in need of repair, with around 7 per cent being more serious with an eventual risk of collapse.

And in Germany, a report from the Federal Highway Research Institute last year found 12.4 per cent of Germany’s road bridges were in bad condition, with around 12.5 per cent considered good.

In the US, a report earlier this year found that 54,000 of 613,000 bridges surveyed were structurally deficient. These bridges are crossed 174 million times each day.

Yeah Hammersmith flyover looked dodgy for years

https://singletrackworld.com/forum/topic/is-the-m4-flyover-safe/

Just the concrete crumbling, but I still wonder, in light of the Genoa tragedy