Miami Beach, Champlain Towers South apartment building collapse, Part 17 14

[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
Miami Beach, Champlain Towers South apartment building collapse, Part 13
Miami Beach, Champlain Towers South apartment building collapse, Part 14
Miami Beach, Champlain Towers South apartment building collapse, Part 15
Miami Beach, Champlain Towers South apartment building collapse, Part 16


SF Charlie
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[FJBnomics]

In SFCharlie’s GIF, I see the cloud of dust from building collapse originating closer to column I9.1 and moving East as it vents. It appears to me, the well coated pilaster at South wall was an earlier dust blast, when the parking garage/pool deck collapsed along on near K line.

EDIT: In photos there was a white PVC line attached to east side of planter wall near pool room exhaust fan location. I also saw what appeared to be irrigation lines inside the planters. Would it not be logical that the plant irrigation system kept the south wall K line pilaster wet, thus the pilasters to the east were not as damp due to no irrigation system near them. Here is image IanCA posted above showing what appears to be white PVC irrigation line.

Look closely at image below. Looks like rebar between south wall and slab is still there, but missing concrete where PVC pipe turns down to garage and Exhaust Fan Can laying to the west. Looks like at that hole everything on one side fell West and on other side it fell East. Also note it appears the structural slab and topping slab that was previously attached to exposed rebar, did a Back Flip to the East.

Like SFCharlie’s Bullwhip analogy

Very interesting!

:

 

[Nukeman948]

I think your observations agree with the point I'm trying to make.

Wrong. I'm repeating myself but, none of the dust patterns I see indicate a larger quantity of dust coming from that one location.

What I am seeing is indicative of a gradient in the moisture on the wall and its ability to retain dust. Any dust that was expelled with enough force to reach the balconies 40' up or more will be distributed over a much larger area, that gradient will be observed over a much larger area, and will not cling to dry vertical surfaces.

Now, if we can agree that this dusting event was the first one, caused by the pool deck collapse, that would imply that there was a much larger air and dust blast as the entire building fell. This second blast would have blown all of the dust off the walls and cars from the first dusting except for where it was stuck to the wet surfaces. I'm repeating myself but, none of the dust patterns I see indicate a larger quantity of dust coming from that one location.

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https://youtu.be/p8_FOQ7-P30

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[Sym P. le]

 

[SFCharlie]

twitter iPhone video with NIST frames inserted 2

SF Charlie
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[SFCharlie]

June 15, 2022, Update on the NIST Champlain Towers South Investigation

SF Charlie
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[Jeff Ostroff]

They showed some cool comp[uter imaging and modeling on his insider video on that June 15 update

 

[SFCharlie]

Just when you thought it was safe to go back in the water...
Link

SF Charlie
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[IanCA]

I hope the latest gif will shed some light on the timing of the huge spurt of dust sent into the air at the southwest corner of the pool deck.

@SFCharlie, thank you very much.

 

[IanCA]

Sym P. le (Mechanical)15 Jun 22 18:02

Thank you very much for that image. The changes in brightness/ contrast/ saturation/ color balance? really help to make the thickness of the dust on the wall and column stand out.

 

[Sym P. le]

... some cool comp[uter imaging and modeling

Interesting also that he has the K column highlighted (direct video link)

 

[IanCA]

What I am seeing is indicative of a gradient in the moisture on the wall and its ability to retain dust.

Thank you for taking the time to help me understand your thoughts on this topic.
Can you help me understand why:
1) Why the dusty column appears to be so much more dusty than the adjacent column to the East when the prevailing wind was mostly from the East that evening. Meaning that the pool equipment room exhaust and plant moisture was being blown away from the dusty column. Was it not?
2) Why the dusty column appears to be quite evenly coated with dust from top to bottom when the bottom half is protected from the free flow of the wind by the adjacent wall (with the water cooler) and the top half is relatively exposed to the flow of the prevailing wind?

Here is an earlier image with annotation added for clarity:

 

[SFCharlie]

I would like to ask if the dust is due to the huge quantity of the blast just as the east portion to the tower starts to collapse?

SF Charlie
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[Debirlfan]

Am I the only one who finds the apparent lack of dust on the plants to be odd? They're near the dusty column, and if there was any dew, it seems the leaves would have been wet?

 

[MaudSTL]

Is it possible that the darker pilaster was at some point restuccoed so it is simply a different color from the other pilasters? I have seen irrigation systems damage nearby structures, causing them to need repairs. The property manager would be able to tell us…

 

[SFCharlie]

Is it possible that the darker pilaster was at some point restuccoed so it is simply a different color from the other pilasters?

Since the sides of the column are still dark brown and the walls just to each side of the column appear grey in that area, I suspect dust.



SF Charlie
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[Reverse_Bias]

One more thing I noticed from the high res gif. There appears to a bend pretty close to the shear wall in the central floors of the X10 stack.

 

[IanCA]

Is it possible that the darker pilaster was at some point restuccoed so it is simply a different color from the other pilasters? I have seen irrigation systems damage nearby structures, causing them to need repairs. The property manager would be able to tell us…

I thought the same thing when I first noticed it but we can rule that out MaudSTL, because the wall and column were back to looking clean and consistent after a couple of rain showers and before July 4th. Please see below.

 

[IanCA]

Am I the only one who finds the apparent lack of dust on the plants to be odd? They're near the dusty column, and if there was any dew, it seems the leaves would have been wet?

I think that is a good observation. I think one possible explanation is that the plants have tilted to the north away from the wall. If dust was primarily forced directly upwards from the debris (from the deck) immediately adjacent to the wall the plants would be far enough out of the way to avoid being directly coated.

Looking at the image posted by zebraso on 13 Feb 22 03:41 we can see there was dust on the plants but apparently not as think as it is on the column we are discussing. It also shows how far the plants had tilted to the north.

This drone view from overhead, taken later after the rain, shows the size of the gap between the plants and the wall.

 

[zebraso]

It looks like the planter soil did not stick to the pitch inside the privacy wall, but the dust did. Electrostatic charges?

 

[Debirlfan]

If the plants were sufficiently root-bound, they probably 'contained' the dirt, especially if the soil was damp.

Also consider - if they were root-bound, that would contribute to adding some pressure on their container. One more stressor adding to the problems with the deck?