Miami Beach, Champlain Towers South apartment building collapse, Part 13 44

[SFCharlie]

A continuation of our discussion of this failure. Best to read the other threads first to avoid rehashing things already discussed.
Miami Beach, Champlain Towers South apartment building collapse
Miami Beach, Champlain Towers South apartment building collapse, Part 02
Miami Beach, Champlain Towers South apartment building collapse, Part 03
Miami Beach, Champlain Towers South apartment building collapse, Part 04
Miami Beach, Champlain Towers South apartment building collapse, Part 05
Miami Beach, Champlain Towers South apartment building collapse, Part 06
Miami Beach, Champlain Towers South apartment building collapse, Part 07
Miami Beach, Champlain Towers South apartment building collapse, Part 08
Miami Beach, Champlain Towers South apartment building collapse, Part 09
Miami Beach, Champlain Towers South apartment building collapse, Part 10
Miami Beach, Champlain Towers South apartment building collapse, Part 11
Miami Beach, Champlain Towers South apartment building collapse, Part 12


SF Charlie
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[SwinnyGG]

Seems like the conjecture is on your part

I have been directly involved in the design process on multiple large scale multi-family construction projects, several of which have included amenity spaces placed at grade on top of excavated parking decks. I've partaken in the construction of nearly a billion dollars worth of cast-in-place concrete structures of various types, and been in the primary field supervision role on about 1/3 of those projects and counting.

What you're implying, that during the design process, the engineer says 'I'm going to put bollards here/space these concrete planters/size this gate so that no one can drive heavy equipment over this deck 30 years from now' is not something I've ever heard, even in passing, let alone as a design constraint.

I'm not saying it's impossible; there's probably ten thousand years worth of structural design experience in this thread, and if those fellows chime in that this is something they do, I'll happily eat my words. But I think it's very unlikely on any project, and even less likely on this particular project where the quality of the design work is already in question.

And, again, none of this matters because it's all pure conjecture. The point I'm making in saying that is that it's time to move on. Talk about what you can prove.

Just because some equipment exists does not mean it will be allowed to be used on any job site.

I agree. And just because some specs exist detailing what is and is not allowed, doesn't mean they were followed.

This is exactly why, in the modern construction world, we plan AND document. Planning means nothing if the crews don't care, and most of the time they don't - because working safely and using the right equipment is not always the fastest way.

But then you also have to explain how they carted those 20-foot palm trees onto the pool deck.

If I were a betting man, I would bet they flew them in with a crane. But there's no way to know unless someone finds documentation of what was actually done (as you've already said).

 

[Red Corona]

Why are we talking about whether people might have done stupid things on the pool deck in 2017 (or even in the 90s)? I know structural failure can be slow, but surely that's irrelevant to the building collapse - something must have overloaded some part of the structure within hours or at most days of the collapse, right?

The addition of the sand and pavers did bring the pool deck up to near capacity though, Building Integrity did a video highlighting that and I believe there were some posts in an earlier thread trying to do the maths on here too.

 

[SFCharlie]

I gave an estimated surcharge two or three parts ago from waterproofing, sand layer and pavers

Yes!, and some of us are paying attention, and Thank you!


SF Charlie
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[SwinnyGG]

surely that's irrelevant to the building collapse - something must have overloaded some part of the structure within hours or at most days of the collapse, right?

Not necessarily. It's clear that ongoing maintenance of this structure was a problem; it's possible that a modification to the building significantly lowered design margin, which created a situation where lack of maintenance or even the normal slow structural degradation of the building over time (which happens even in well-maintained buildings) took one member or many members below the required capacity and triggered a failure.

Whether or not a forklift/pallet jack/walk behind skid steer was ever driven onto the pool deck and caused a discrete failure due to the associated point load is similar to the added load from the pavers themselves; it's possible that one of those was a factor in the collapse; but at this point, with the information we have in hand, we can't know one way or the other.

 

[Demented]

@Jeffostroff
The 1996 palms. 14ft tallest palm. 45 gallon sized root ball. Most palms were 25 gallon, 80-12ft wee little things weighing in at around 350-450lbs. Boom trucks and a crane were on site. The landscaping was done in conjunction with waterproofing, deck repair, garage ceiling repair, and fixing the broken root clogged planter drains. I cannot imagine they'd hire other heavy equipment to do what their already expensive as hell per hour rental can do.

If any idiocy with scissor lifts or lulls was done, it was the crew after the 1996-1997 crew.



Precision guess work based on information provided by those of questionable knowledge

 

[Jeff Ostroff]

Swinny, how do you know the size and weight of these palm trees, do you have other documentation that we have not seen?

How do you know that boom trucks and cranes were used? A boom truck parked along the 87 ave alleyway to the beach is not likely to reach that far over the pool wall, across the pool, then across the pool deck without tipping over a boom truck.

 

[Demented]

I read the permits.
*shrugs*

The info is in there. You just gotta read, not look.

Edit: I'm just curious. How did they get a lift or fork jack thingy of some sorts onto the pool deck? What pathway did they drive it onto? Or did they use the crane or boom truck on site to lift it? I'm just curious. I fancy myself skilled at sketchy forklift driving, but there's only 2 ways I'm getting a fork truck on that deck. From the sky, or crashing through a wall roadrunner style.

 

[spsalso]

Roadrunner goes around. Coyote crashes through. Sometimes with an Acme Forklift.




spsalso

 

[Jeff Ostroff]

The landscape drawing for the 1996 permit does show a few palm trees with a height listed. But most palm trees on the pool deck are showing no heights, nor root ball size which is why I asked about that.

The 2 Lantana Palm trees at the planter outside Sara Nir's unit 111, are not showing any height on the drawing. which again is why I asked where did he get that info?

If it is not specified in the permit, how does he know?

If you look at photos from 2017, you can see these 2 palm trees in question, one right over M11.1, and the other palm tree over "L11.1". Both trees are the tallest trees there, over 4 feet taller than the other trees. That extra 4 feet may not seem large to you but it does add about 800 pounds per tree in that area.
So now we have an additional 1600 pound dead load right on top of the planters in an area we know to be weak and leaking through to the garage below.

And no matter what, by 2017 those trees were all pushing 20 feet. They are like parked cars sitting on the pool deck which was not designed to park cars on it.

Also, here's how a forklift would get onto the pool deck:

Method 1: Long bed truck with forklift hanging off back parks on Collins Ave in front of the building. Driver with forklift drives all pallets of bricks over the above-ground parking deck east toward the pool fence, then they open both gates and it drives on the pool deck, and distributes the pallets all over. Probably done in 30 minutes, these guys are in and out fast. I have never seen them stay at any of my sites longer than 15 minutes.

Method #2: Boom truck pulls up on 77th alongside the pool and lifts pallets over the wall and sets them down by the jacuzzi. Then forklift or pallet jacks are used to move the pallets into their positions around the pool deck.

Method #3 (Less Likely): Long bed truck parks on NW 88 St on the northside of building and forklift is used to drive the pallets south along the east border of the property until they encounter the gate, and they have to remove the 2 gate panels on either side of the gate to fit the forklift through.
.
. I spotted this typical long bed delivery truck the other day, on its way to drop off pallets of tile at the customer. Note they only use forklifts. This is what I receive at all my sites, dropping off tile, paver bricks, or wood flooring and 16ft baseboards.

.
.

 

[SwinnyGG]

If it is not specified in the permit, how does he know?

I never said anything about knowing the height of the palm trees...

I said if I were a betting man I would bet they flew them in with a crane (because that's how I would do it) but that there's no way for us (including me...) to know for sure what exactly they did.

 

[Jeff Ostroff]

It was @demented who said: "The 1996 palms. 14ft tallest palm. 45 gallon-sized root ball. Most palms were 25 gallon, 80-12ft wee little things weighing in at around 350-450lbs. Boom trucks and a crane were on site."

while some of his info is correct, not all of it is. Nowhere could I find root ball sizes, or that boom truck and crane were present on site

But anyway, by time 2017 rolled around these palm trees were no longer "wee little things" weighing 350-450. The trunks get wider and they get taller, they grow about a foot per year and level off about 20-22 feet, depending on the breed.

 

[AutisticBez]

Also, the payers won't have been done in 1 day either. Work on a small area at a time. Maximum 1 pallet of pavers and a bin. You've got to understand the pace of work is a crawl. When I was doing work, the boss only came down once a week. The other 4 days we did jack. My knees were in pain from standing around doing nothing for 8 x 4 hours. Then when the boss came down he still had no work. Its the easiest job of my life. Rofl. Only concrete workers work fast.

 

[Demented]

@Jeffostroff
The tree supplier is listed in the permit. Rootball, gallon pots, and weight are going to be standard sized at certain tree heights. Pot gallon sizes will be standard with height and weight of trees. On the landscaping layout, it's pretty obvious they only had installation of smaller trees on the pool deck. Likely to ease installation, and to not block the view of the pool/ocean. Larger trees were reserved for the front of the property.

There's more information around the same work project scattered all over. I'm not responsible for the Town of Surfside's organization practice. I'm sure you've seen all of the elevator inspection reports and permits scattered all over the place in things like individual unit interior permits and spa tile resurfacing. I'm pretty sure the town is still just releasing social security numbers, passport photos, drivers licenses, etc without a care in the world too.

@Spsalso
Thanks for the correction. You all meant what I knew though.

@SFCharlie
I figured the file out. Had to add on the file extension manually.
Still just as confused. So I guess, wtf is that rebar cage?

 

[SwinnyGG]

Also, the payers won't have been done in 1 day either. Work on a small area at a time. Maximum 1 pallet of pavers and a bin. You've got to understand the pace of work is a crawl. When I was doing work, the boss only came down once a week. The other 4 days we did jack. My knees were in pain from standing around doing nothing for 8 x 4 hours. Then when the boss came down he still had no work. Its the easiest job of my life. Rofl. Only concrete workers work fast.

Uh... that's now how it works in commercial construction at all. Between the pavers, trees, and all the other little stuff they did all at once this was a contract worth a couple hundred grand probably... no one was standing around 4 days a week.

 

[Demented]

@SwinnyG
There actually was a lot of of standing around waiting on people in both of the major renovation projects. Permit extensions even at times simply due to some contractors not showing or leaving nearly just as they got there.

In a normal situation, I agree, that shit normally doesn't happen, but there was a lot of disorganization and at will stuff with the first engineering firm that took on beautifying CTS. It's cool though. The workers were allowed to inspect and pass their own work.

 

[SFCharlie]

Well, there are 30 references to "palm" and 41 to "paver" in this part 13, so... must be time for a new part:
(I wonder if we could leave the palms and pavers here?)
PLEASE STOP POSTING IN THIS PART 13 PLEASE
Please allow me to move the discussion to Miami Beach, Champlain Towers South apartment building collapse, Part 14, Thank-you.
Someone Please close this post to new postings, or message me how to do this, Thanks.

SF Charlie
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