Miami Beach, Champlain Towers South apartment building collapse, Part 12 60

[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

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[Optical98]

Jeff Ostroff

I highly suspect there are only about 6 people posting on this entire forum, each with as many multi-personality sock accounts they use to derail any serious concepts or convos.

 

[AutisticBez]

Vehicle collisions with columns cause a bottom shear. The damage doesnt occur at impact. The bottom is the weakest point.

M11.1 did not puncture shear, so where is it? A car didn't do it, then how the hell did it collapse? Was it the one pool deck column that managed to survive a similar fate?

Its ground zero, what happened to M11.1. Find me this column intact.

 

[AusG]

Looking at it another way: RC structures have been built since early 1900s and RC is the most common structural material in a world 60% urbanised. There are 5 billion adults in the world, (so 2.5 billion stupider than the median) driving 1.4 billion automobiles, many in places with imperfect building standards. If car/column interactions brought down mediocre buildings we would not be guessing about it here. Sure, maybe that one time in a billion that the conditions are just right, the relative zephyr/love tap of a car on a column might precipitate a chain of events like this, but even if so the question for builders and designers would be those preconditions, the design and the construction, because cars and idiots fall within the design brief.

 

[Nukeman948]

What evidence shows M11.1 did not puncture shear? It could have been the first one to puncture shear but we can't know for sure because it got buried under 13 stories of rubble. If the damage didn't happen at impact, did it happen a week later? Maybe before the impact?

(please excuse me while I switch accounts, and personalities because... uh... reasons)

 

[Spartan5]

Question:

What happened to M11.1?

Answer:

Its ground zero.

 

[Optical98]

^ Ahemm....

 

[Spartan5]

I just found evidence of multiple additional car strikes. Thoughts?

 

[Jeff Ostroff]

So it's like Murder on the Orient Express? Everyone was in on it? every owner drove a car in a pillar? That pillar in the photo above is on the northernmost edge of the property and is bent like that because the whole building came down on it, causing it to bend.

 

[Spartan5]

“So it's like Murder on the Orient Express?”

That’s been the approach to this here for the last ten threads or so. It’s all most have at this point. Barring any other videos or photographs from that night, it’s all that there’ll be for some time.

 

[Spartan5]

Interesting theory. Where are these items in the pile?

You will have to credit others for identifying the items. I can only claim the creative writing behind the theory.

 

[AusG]

Just to go back to the real world for a sec. Isn't that column pic the visual evidence right there of columns being undersized for the amount of steel?

 

[AutisticBez]

Jeff, its more plausible then a video of you pointing at expansion joints and minor spalling occurring at the bottom corner of that joint, and making out that the entire building is going to collapse based on a little water seeping through an expansion joint.

Cars hit stuff, I know one person who wrote a car off on a column. So it does happen. 40km/h is a slow speed, and between the column and the entry is like 100 foot downward slope, my car could do that just rolling naturally without any gas.

 

[Nukeman948]

40km/h is a slow speed, and between the column and the entry is like 100 foot downward slope, my car could do that just rolling naturally without any gas.

LOL, You're not even close to reality. Let's find some real numbers and see what it works out to.

From the prints we have a grade level of 10 feet 10 inches. The garage floor is 2 feet 2 inches which gives a drop of 8 feet 8 inches.
The ramp length from the property line to the bottom at column line 8 is only 83 feet 4 inches.

Well I'm not smart enough to figure out rolling and wind resistance for your Australian hooptie and how to apply all that to acceleration on a ramp, so I skipped that nonsense and found a free fall calculator online and the numbers only come out to 26km/h. Surely the acceleration on a ramp will give a much slower speed than free fall.
Feel free to check my math.
And please share with us your evidence of a real car and how you determined it was going precisely 40km/h.

 

[ChiefInspectorJ]

Can anyone find pics of the main step beams? The one at the building line is 12" x 19" which also is holding up the weight room. The step beam behind the planter has 2 drops in it with BM A's under it somehow attached to the step beam.
Also if someone can do calcs on this beam with a cantilever moment of the deck and planters added to the other loads?
The columns appeared to be the strongest element in the building.
They are a red herring and performed way beyond capacity..

 

[Red Corona]

Once again there's no way a car could have run into M11.1, which is right at the bottom of the parking ramp, at any time before 01.15 (well after serious problems had already started as reported by the Nirs in 111), because people coming into the garage would have seen it. That's even if you think a car hitting a column could theoretically fracture it and damage it structurally.

> M11.1 did not puncture shear

What's your evidence for that? M11.1 was buried under the debris of the initial collapse, and then also by the eastern section, and during the clearance heavy equipment was dragged all over it.

 

[SFCharlie]

You will have to credit others for identifying the items. I can only claim the creative writing behind the theory.

At least, some of the item identifications have been debunked in the thread they were posted in, and their poster, in that case, acknowledged the incorrect ID and asked for other suggestions!


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[SFCharlie]

An Ancient Girl Had Parents From Different Species. Scientists Are
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I think google ads has figured out the audience here...

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[Spartan5]

At least, some of the item identifications have been debunked in the thread they were posted in, and their poster, in that case, acknowledged the incorrect ID and asked for other suggestions!

The poster said (to paraphrase) “yeah I guess that AC unit is only as big as a construction cone as you have pointed out.” They left the rest of their theory that follows ‘hanging’ so to speak. Mine is at least as plausible as theirs.

In any case, I will agree with you that maybe those aren’t AC units in that picture. What else do you think it is they could have loaded on the car before it lost control and drove off the roof?

I believe this object is the condenser of an air conditioning unit. Near this object lies a square piece of sheet metal with rounded corners that has a circular hole inside. I believe that this the metal top of the air conditioning unit. One would expect the cable to go through this circular hole as well. But one can see a slot in one side of the top that has allowed the cable and top to be separated. This slot could have been made by the recovery crew to allow easier inspection of the top, or could have been made by pulling on the cable by a power shovel while the top was still covered by the debris pile.

Now, I would wager that it is no accident that this cable extends into the internal condenser part of an air conditioning unit. Normally, the top of an air conditioning unit is covered by a wire grating that would prevent a cable from randomly penetrating inside. However, if one wanted to raise or lower an air conditioning unit with a cable, instead of putting it on a platform or using a lifting sling in some manner, it is easier to just remove the circular grating in the metal top and pass the cable hook through the top opening, then around a compressor support bracket at the bottom of the condenser, and then reattach the hook to the cable again. This alone would indicate that a human being was responsible for attaching the air conditioning unit to the cable.

So, why is the object of interest (whether an AC or some other object) still intact and still attached to the cable after the building has collapsed? Clearly, something went wrong during the raising or lowering of the object that prevented the person involved from detaching the cable. This something that went wrong could not have happened near the top of the building, because then nearly all of the cable would still be in the winch and not strewn all over the debris pile with the object still attached. Therefore, it must have happened near the pool deck. But if the winch malfunctioned in some way to cause the object to fall freely to the pool deck with the cable still attached, then the object likely would have been dented beyond all recognition by the collision with the deck floor. Clearly, the TikTok video shows that this object is still relatively intact. But what if the something that went wrong occurred just a few feet above the pool deck? This could happen if the cable was not long enough. In this case, the users involved might be tempted to gain a few more feet to safely put the object on the deck by tilting the crane at the top a little bit. But when this was done, the change in the crane’s center of gravity could have caused the crane to press against the parapet, causing a moment arm of over 7 feet (4 feet of parapet height plus 3 feet of clearance) with over 300 pounds of force to be applied. This may have caused part of the parapet to give way, sending it crashing down onto the most sensitive part of the building’s structure; namely, the beam between column 27 (column M10) and column M11.1. In this case, the object of interest would fall only the distance of one floor plus a few more feet, which would enable it to stay relatively intact. It would also have resulted in the object of interest falling midway between the hoist counterweights on the debris pile as observed in other photos because the object would have been pulling down on the hoist structure, thereby keeping it centered on the object.

Some further thoughts about this scenario are as follows:

1) It is likely that there was a second person at the bottom of the building as well as one at the top. This is likely because someone is required at the bottom to remove the hoist hook from the object and cart it away, while someone at the top controls the hoist. This second person was likely in cell phone communication with the one at the top. This would have allowed almost silent operation under normal circumstances after 12:00 AM at night. But this second person might have been seen by a surveillance camera having a line of sight over the patio area of the pool deck. This person at the bottom would have been exposed to the falling parapet and may have been injured or even worse. Nothing has been mentioned by the recovery crew about finding a person near the object of interest.

2) The amount of cable required would have been at least 120’ 8” to cover the distance from the penthouse roof floor to the pool deck below. An additional 8 feet or more would have been required to get over the penthouse parapet (4 feet tall), the height of the air conditioner (3 to 4 feet), and either a cable pulley or a winch (1 foot), thus adding an additional 8 to 9 feet. Therefore, the total cable length required would have been 129 to 130 feet. Most commercial winches have only 120 feet of cable, some have 130 feet, but very few have over 130 feet. Therefore, the amount of cable needed was right at the limits of most available winches.

3) With the pulley or winch needing to be 8 to 9 feet above the penthouse floor, the hoist would have been quite tall. Also, it would have needed to extend at least two to three feet over the parapet to clear a 3 foot square object like an air conditioner, so it would have required a counterbalance over 8 feet long with weights greater than 300lb x 3/8 = 100 lbs to stabilize the hoist in two directions. Two hexagonal weights on rods were found on the debris pile that could serve this purpose. Also, this large hoist would likely have been present when the building inspector was on the roof the day before the collapse, so he should be able to give a description of the hoist.

4) A winch would have been attached to the hoist structure. This winch would have fallen to the pool deck below with the hoist structure, probably causing the winch to be seriously damaged. An object was found on the debris pile that appears to be this winch, with the motor and cable spool separated from the housing. However, no other parts of a hoist structure have been observed except for the two counterbalances and possibly a pulley.

5) Operation of a hoist on a roof requires that the hoist have a tie-down cable to a secure building structure to prevent it from falling. There was no such secure building structure on the penthouse roof near the hoist at the time. Therefore, the workers may have used the aluminum framework of the air conditioner mounts as a tie-down structure. Evidence of an aluminum framework with a second air conditioner attached can be found on the debris pile at the end of the ramp.

6) Could the falling of the penthouse parapet wall above and its crashing to the deck correspond to Maud’s first stage of collapse? The second stage of collapse has been identified as being caused by the falling of the pool deck, which might have taken place after a short pause.

7) Could the “knocking sounds” or “hammering on the roof” heard by a tenant and by the night watchman before the collapse have been caused by compressed air guns being used to remove air conditioners from their mounts prior to moving them?

8) Could the weird smells noticed by some tenants have been caused by the refrigerant being released from the air conditioners that had fallen? This refrigerant is a gas that normally has a faint smell like either ether or chloroform that some people might find to cause a disagreeable odor. Each air conditioner has about two to three pounds of this gas inside that takes about a half hour to release completely. With a total of about sixty or more air conditioners on the roof falling at the same time, this would have caused over 150 pounds of this gas to be released all at one time, which would have been noticeable throughout the collapsed building.

9) There may be a witness who can tell us who was on the roof that night. The security desk employee should have seen anyone who entered the elevator after hours while wearing working clothes. And this same security desk employee may also have seen them exit the elevator to leave the building after the pool deck collapsed, which he/she should also have seen by watching one of the security cameras. Has anyone asked the security employee about these topics?

I will leave it to others to explain who may have been on the roof that night to trigger this sad sequence of events because of potential liability concerns. Suffice it to say that the trigger for the collapse was likely an industrial accident created by carelessness and stupidity, and not merely by structural deficiencies as bad as they were to everyone’s agreement, including my own. Without this trigger, no one knows how long the building could have remained standing with all its deficiencies. The case is equivalent to an old and unhealthy person being run over by an automobile driven by a careless driver. No matter how old or how unhealthy the old person is, the cause of death is still an automobile accident caused by a careless driver. One can introduce new health measures to keep an old person functioning longer, but only by stopping careless driving can one prevent automobile accidents that cause the death of older people.

 

[Debirlfan]

Do I think that a car might have hit a column? Yes. Do I think that a car came speeding down the ramp and totally demolished a column? No.

We know that some of the columns were (at best) of marginal size as originally designed. In many cases they appear to have had too much/too little rebar. Concrete was of questionable quality. Pavers/planters/water added additional weight, and provided access for seepage of water. Previous repairs are highly questionable.

Now, consider the possibility that one of the tenants is not a great driver, and occasionally 'nudges' the column next to their parking spot as they are parking. Maybe it happens once, maybe it happens a dozen times over the course of a year or two. There's little visible damage to the column, maybe a chip or two on the corner--but is the impact/vibration enough to internally crumble already damaged concrete, and perhaps loosen it from rusty rebar? Could the structure have been so bad that one little bump (or a series of them) have been the straw that broke the camel's back and brought the whole thing down?

 

[SFCharlie]

Several people including at least one YouTube poster on this thread, have hypothesized that the deck pulled the column down.

Miami Condo Collapse: How A Pool Deck Brings Down Buildings


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