Fatal wall collapse during restoration after engineer says demo it 6

[ACtrafficengr]

Engineers Warned Landmarks Commission Salvaging a Synagogue Would Be Dangerous. Then a Worker Got Crushed to Death.

"the general counsel for the landmarks commission had “instructed” him not to again bring up his recommendation for a full demolition so as not to “offend” the commissioners who were insisting that parts of the deteriorating building must be retained."

FSCK the commissioners' feelings. The general counsel should get fscked, too.

Sorry about the chloride content.


My glass has a v/c ratio of 0.5

Maybe the tyranny of Murphy is the penalty for hubris. -

http://xkcd.com/319/

 

[phamENG]

SwinnyGG - I agree with you 100%.

 

[JAE]

Agree also with SwinneyGG.

Some speculation/comment:
I didn't read anything too specific in the article, and maybe it did occur, but the various engineers involved in this should have perhaps done more than just say "it's dangerous".
They might have but I didn't see in article where they got too specific other than to say there was too much debris along the wall base to allow shoring structures to be installed safely.

There are many ways to brace walls, etc. and many (most?) structural engineers don't have a ton of experience in construction shoring and bracing - it's a specialty.

It's possible that some specialist out there perhaps knew of ways of overcoming the situation safely.

So it's important I think for the engineer to adequately describe why the walls were dangerous and what sort of failure mechanisms were possible and why the engineer thinks that restoration wasn't possible.
1. This helps the contractor to fully understand what they are up against.
2. Helps the contractor know whether they are out of their league or not
3. Forces the engineer to understand all the failure possibilities
4. Helps the engineer convince those in the "hysterical" societies and agencies to realize that there's really, no really, yes really, a concern here.
5. Helps the owner understand the economics of the situation when comparing tear-down to renovate.
6. Further covers the engineer's arse.

 

[IRstuff]

adequately describe why the walls were dangerous and what sort of failure mechanisms were possible and why the engineer thinks that restoration wasn't possible.

5 stories of unbraced brick wall; nuf sed.

TTFN (ta ta for now)
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[3DDave]

It's like when a bomb disposal guys says "If you see me run, try to keep up."

There's no need to go into more detail when the engineers recommend demolition. They are running away.

 

[JAE]

IRstuff....well yes. There was a dangerous condition there but my point was that people on these historical committees don't always understand or see the obvious...yes some are that dumb.

I was just speculating that the engineer said no - and possibly didn't give any reasons or explanations...and "why the engineer thought that the restoration wasn't possible".

Five stories of masonry CAN be repaired and braced. It just takes folks who know how to do it.
I have designed masonry wall bracing to brace 5 stories of 4-wythe brick and no floors behind it.

It can be done....just expensive as hell and only if there wasn't debris along the base. But you have to explain it.

 

[SwinnyGG]

So it's important I think for the engineer to adequately describe why the walls were dangerous and what sort of failure mechanisms were possible and why the engineer thinks that restoration wasn't possible.
1. This helps the contractor to fully understand what they are up against.
2. Helps the contractor know whether they are out of their league or not
3. Forces the engineer to understand all the failure possibilities
4. Helps the engineer convince those in the "hysterical" societies and agencies to realize that there's really, no really, yes really, a concern here.
5. Helps the owner understand the economics of the situation when comparing tear-down to renovate.
6. Further covers the engineer's arse.

I (gently) disagree with this.

If I were in a similar situation to this contractor, as soon as the engineer says anything like 'hey this demo looks to carry some significant risk, there needs to be a plan in place to mitigate that risk' (or whatever) the contractor is now duty bound to figure it out. I don't believe I should rely on the engineer, who has likely done a cursory site visit but may not have dedicated significant time to evaluating the issues found, to identify every single threat or to provide solutions to mitigate them. That stuff is 100% on me. Protecting my guys is my problem to solve.

I would definitely value any input the engineer has, and would very much appreciate their support on my side of the argument if the discussion with the owner becomes contentious, but in my mind it's on me to fully evaluate the issues and find solutions. If doing so exceeds my capability or knowledge, hiring the appropriate third party is also my problem to solve.

In my mind the division of responsibility is relatively simple - engineers tell us what we need to install to give the owner (or their architect) what they want. My job is to figure out how to build it. I don't believe the EOR has any responsibility beyond notifying us that there may be an issue - once that happens, evaluation and mitigation are 100% on me. Doesn't mean I never ask the EOR for their opinion or to weigh in on options - I do that all the time - but that doesn't reduce my level of responsibility.

I recognize that this opinion probably disagrees with some engineer's points of view, and potentially the relevant codes of ethics and all that - but it's my point of view on the due diligence I need to be doing in these situations. Any help, beyond identifying an issue, that I get from the engineer is just gravy.

 

[phamENG]

SwinnyGG - I agree that the responsibility for execution stays with you, but JAE is right that the engineer is also responsible for the list he posted. Oftentimes in these projects, it's design-bid-build. So when we walk on site to assess the building for the first time, it's not always clear who will be bidding on the project much less who will get it. So I do a detailed assessment of the building - joist by joist and brick by brick if it's accessible - and determine what risks I see and what my recommended mitigation is. That all goes into the contract documents for bidding. That way, the contractor has a better idea of what they're getting into before hand. If it's beyond them (JAE's #2), they don't have to waste their time or the design team's by attending a pre-bid. It also ensures that a low bidder can't come back and claim they didn't know it was this bad.

Once the contractor is on site and particularly after they have a contract, the responsibility shifts to execution and the contractor must do their own assessment and risk mitigation.

So there's room for both to coexist.

 

[LionelHutz]

We don't know what details the EOR provided. We do know there was a contractor on site, and at that point in the process I 100% agree with SwinnyGG
that site safety is the contractors responsibility.

 

[CWB1]

Apologies if I missed it, but to clarify my earlier question a bit - Does the AHJ ever require an engineering signoff on safety plans for these more-complex projects?

I dont disagree that the contractor needs to own site safety bc ultimately, they're the ones onsite and easier projects like the typical residential home demolition via excavator bashing shouldn't need engineering review/approval. My concern is simply preventing contractors from getting in over their heads via assumptions. Wish I had a nickel for every time a tradesman misunderstood a critical instruction or deemed their work "close enough." Reality happens, its why I've always demanded an engineer QC any test rig or prototype that could prove dangerous alongside the responsible trade. I imagine playing brick-Jenga gets very complicated, very fast.

 

[JAE]

Just to be clear, I was never talking about responsibility for site safety....of course that's on the contractor.

I was suggesting that if there was an engineer involved, then said engineer should be clear to communicate the "whys" of their recommendations to help everyone involved.

 

[SwinnyGG]

Apologies if I missed it, but to clarify my earlier question a bit - Does the AHJ ever require an engineering signoff on safety plans for these more-complex projects?

I've been in on some pretty big stuff, and in my experience the answer has never been yes, with the exception of things mandated by OSHA (excavations over 20 ft, etc). Other jurisdictions may vary of course.

 

[CWB1]

Thanks for the clarification.

 

[phamENG]

Other jurisdictions may vary of course.

This. It's highly jurisdiction dependent. I've worked in jurisdictions that scrutinize everything, and I've worked in jurisdictions without a full time building inspector. It's largely an urban/rural thing, though not entirely. Urban centers tend to have stricter rules and larger staff for processing permits and inspecting work, whereas rural areas lack the resources and tend to let people do what they want, oftentimes because the lack the manpower to enforce anything.

 

[SWComposites]

the ******* general counsel for the LPC should be at the top of the list and should be sued for every penny he/she has.