Ronan Point bites again

[LittleInch]

One of the most notorious UK building disasters in 1968 - Ronan Point - has re surfaced in an even older building in Bristol this week.

https://www.theguardian.com/society...ed-and-what-is-bristol-council-doing-about-it

The flats / apartments were built using Large Panel system design - basically a bunch of interlocking concrete prefabricated sections supposed to be bolted together and filled with concrete. Apparently some inspections showed that it hadn't been constructed in the way it was supposed to and was essentially a pack of cards. They now think its been like that since it was built.

But it does show that how do you decide something is about to fall down or has an unacceptable risk?? Very difficult when it's been there for over 60 years and is still standing.

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

 

[EdStainless]

There are two risks here.
1. Is it going to fall down without warning (physical risk)
2. Can this property be insured (financial risk)
My hunch is that knowing what is know now this would fail on #2.
Should people be allowed/forced to use a building with this risk?

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

[1503-44]

Many buildings have never received their original design loads, so time standing alone cannot be a valid test of adequacy. If you had an accurate record of loads applied during its history and a detailed inspection report that measured critical variables, that might help determine the level of integrity remaining.

Why not analyze as built info in accordance with current practices.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[LittleInch]

The issue seems to be what happens to the building if it suffers an explosion, large fire or "collision" - not sure what's going to run into it but that's what they said.

This is a Local Authority building so a bit different to a private building ref insurance.

It was built 65 years ago so as-built info is probably a bit dodgy....

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

 

[Tomfh]

If the risk is that “in the event of a fire, explosion or large impact, there is a risk to the structure of the block”, then a full emergency evacuation leaving all residents homeless seems a tad excessive.

That article says there are 575 blocks built that way which makes them likewise at risk. It sounds like all those crummy English public housing buildings you see in the crime dramas were done that way.

They’ve been there for 50 or so years. That’s a decent sample size. I can see why cooler heads suggesting “do nothing”
at least be considered as part of the official set of options.

I mean yes, you *could* immediately strip them all to their bones and fix them like the brave whistleblower suggests, but that’s going to cost maybe a trillion dollars.

That’s money that could be spent building new flats.

 

[FacEngrPE]

Are the flats close to their "design life"? I can see some temporary bracing for the purpose of an orderly relocation, followed by building new flats. As much work as the retrofit would be, new flats could easily be less expensive, particularly when considering that these buildings were not intended to last generations.

 

[spsalso]

"Apparently some inspections showed that it hadn't been constructed in the way it was supposed to and was essentially a pack of cards."

Here in the United States, we tend to do our inspections as the building is being built. This can catch the "..it hadn't been constructed in the way it was supposed to..." problem; which, I think, is the whole point.

I am quite astounded that such a concept apparently hasn't caught on in Britain. And maybe not so much in Florida, either.



spsalso

 

[Just Some Nerd]

I am quite astounded that such a concept apparently hasn't caught on in Britain.

I think this might be more of a problem for Britain 65 years ago rather than now....



----------------------------------------------------------------------

Why yes, I do in fact have no idea what I'm talking about

 

[spsalso]

Good point.

It appears the type of standardized government building inspection I am thinking of didn't happen in Britain until 1984:

https://www.designingbuildings.co.uk/wiki/The_Building_Act

And the subject building does appear to precede that date.


In the United States, it appears the date was about 1905:

https://mypdh.engineer/lessons/history-of-u-s-building-codes/

How very interesting.



spsalso

 

[hokie66]

The US may have laws requiring inspections while the work is proceeding, but that doesn't mean it always, or even usually, gets done by qualified persons.

 

[GregLocock]

Reo installed. Building inspector checks it. Reo removed. SOP.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?

 

[spsalso]

"The US may have laws requiring inspections while the work is proceeding, but that doesn't mean it always, or even usually, gets done by qualified persons."

No, it does not. What an excellent reason to not bother.

In my experience with inspections in the US over the last 40 years, the persons doing the inspection are qualified. Note that I have not worked in Florida.

Perhaps in your locality this is an unattainable goal. Just because you are in a sea of corruption does not mean everyone else is.



"Reo installed. Building inspector checks it. Reo removed. SOP."

Half Moon Bay, CA: Inspector became suspicious, and parked his car overlooking the job site. Great sadness ensued when the material was being, uh, repositioned.



That corruption and incompetence occur is not much of an excuse to not bother to fight it.


Or.

You can argue that it is.



spsalso

 

[hokie66]

I agree with you, except for the high and mighty statement in your post of 15 Nov 2230. And what is it about Florida? Just typical left coast prejudice? And who do you mean is "in a sea of corruption"?

 

[LittleInch]

Maybe not in this report, but others say it is only this block where they have found this issue.

Many of the blocks built in the 1950s and 60s have indeed been demolished and rebuilt as this was more effective and better insulated / fire protected / less likely to collapse....

The issue which has been discussed before is where do you draw the line between over reaction and huge disruption from a forced evacuation of the building. Very difficult for the engineers involved.

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

 

[1503-44]

Once the structural capacity is defined, does this not default to a classic risk management problem.

"The rationale behind risk acceptance is that the costs to mitigate or avoid risks are too great to justify given the small probabilities of a hazard, or the small estimated impact it may have.
Accepting risk, or risk retention, is a conscious strategy of acknowledging the possibility for small or infrequent risks without taking steps to hedge, insure, or avoid those risks."

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[spsalso]

"I agree with you, except for the high and mighty statement in your post of 15 Nov 2230."

Which one of the statements in that post was the high and mighty one? Actually, I think you're missing that it was all written in a sarcastic tone.

"And what is it about Florida?"

Florida? That would be the Champlain Towers South, where the city delegated the inspection process to the structural engineer. Who apparently thought everything was just wonderful.

"Just typical left coast prejudice?"

Don't know.

"And who do you mean is "in a sea of corruption?"

Anyone who thinks it unlikely that another location would have honest competent inspectors. "We don't have them here; how could YOU possibly have them?"


spsalso

 

[drawoh]

LittleInch,

The originali Ronan Point disaster was triggered by a gas explosion. When they pulled down what was left of the building, they found that the contractors had not followed the drawings, and that the building was not to code. They demolished the remaining builds of that set.

Maybe this building has not yet encountered a gas explosion!

--
JHG