Miami Beach, Champlain Towers South apartment building collapse, Part 16 24

[dik]

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Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[Sym P. le]

I don't get it. Alarming, sudden appearance of deterioration, therefore look somewhere else? Logic?

 

[FJBnomics]

Even though I know I can not 'add value' to a SymPle GIF, I thought I would try, while we wait on SF's PowerPointy.

What I am trying to show is correct column labels on some of the columns of current interest, and that the center line of the slab running under the planter 1" drop aligns with Column I14. And Not I14.1 as I incorrectly stated earlier, and that Column 76 is L13.1, unless I made boo-boo, as I have not received the "color between the lines" class yet.......

And all that displayed on the Outstanding GIF, I just plagiarized.

 

[zebraso]

I am wondering how the planter wall reinforced top made it over the trash can without wiping it out. Then I am imaging it was held up for a time by the column. It looks like the piece of wall top that would have smashed the trash can is rotated 90 degrees. Perhaps that portion was hanging down when it fell from the column. Not that it has any bearing on anything. Just trying to make sense where there is none.

 

[zebraso]

Is there an east-west construction join that runs through the corner of the plant where it cracked? It looks to me like there is a demarcation in the fallen deck where the deck south of that line is higher and maybe even resting on the north section. I thought all the construction joints were N-S. I don't know how you would explain them overlapping, so maybe they aren't. But the south seems to be resting higher along that line. I see this without playing with pixels.

Edit: suggested in this photo (tight crop from a WSJ photo previously posted)

Note the garbage can for perspective. pavers and deck south of can relatively planar and undisturbed. Trash can sits at a level a step below. Pavers north of this line are disarranged and deck is desk DIS- continuous. Does it mean anything? Don't know. There is tower debris encroaching from the lower left. did the falling debris cause this fracture to propagate? All an illusion? Time for my pills now.

 

[FJBnomics]

The image is so blurry I can not make out the garbage can. I went to WSJ, and grabbed the image below. Is the first image, the WSJ photo you perhaps took a screen shot of? Your thoughts are interesting, but I am still processing.....

Clearly in the second image below, now that I have high resolution from WSJ, I can see the diagonal break in parking deck that is either radiating towards the trash can and dropped planter, or radiating from?

Did anyone else notice that the planters were to be water proofed in 1979, however "weep holes in planters where practical" ? In detail posted by IanCA.

GREAT way to keep that structural slab soaked around the planters...

 

[zebraso]

that's it. I didn't modify the pixels. I just enlarged the image and cropped off what was not of interest. Now if simply saving a png format image readjusts it, I don't know. There are areas (more than one) of fallen deck that are essentially quite "planar", with the exception of localized punch points and the major trough there in the middle. The line I drew is where there appears a more significant break from any hint of planarity. Debris from the fallen building does not help to decipher it. You can see the angle of the sun better in the full WSJ image to see where shadows would be. When I said I could see this line without adjusting pixels I was looking at SFCharlie's AP images several posts back in this thread. I just think this image was more useful because it's more oblique to the deck even though it's quite grainy at this level. The date of the WSJ photo would help but from what I can see things are in the same state. A side by side comparison would help also.

Edit: About the second image with diagonal break. I realize that was identified as significant by several posters recently. I guess the question is whether that is what is propagating all the way out and near column 76. That's the gist of what I am trying to ascertain.

edit again: Weep holes. I saw that. Where practical? That must be with foresight of the drains clogging after a month of use. Actually not too bad of an idea if the deck would be adequately sloped. And that turned out not to be the case. Are the drains bigger than a weep hole for long?

 

[spsalso]

Do you expect a problem with weep holes that drain from a potentially waterlogged planter onto an exterior deck that is, on occasion, afflicted with rainwater?

I suppose you might if you assume incompetent construction methods. But then, the AHJ would catch that, and require correction. Which, of course, the City of Surfside did.

Or not.


spsalso

 

[Reverse_Bias]

Gotta find every satellite photo available to see if the wet spot on the deck expanded towards 76. It's a mystery how a column head got to be the low spot. A mound should form above the column during the punch shear process, hence the leaks should be between columns or at least a few feet away from them. Also the slab directly over 76 also could not have dropped far without popping out the pavers above it.

Maybe there was some odd internal voids within the slab causing this? It almost points back to the delamination theory.

 

[zebraso]

>It almost points back to the delamination theory.

Sure seems like it. Eye witness testimony of water poring into sunken deck. Voids filled with water that pours out when the deck falls. Josh described 76 as covered with efflorescence and water very wet (from the photo he was shown by MH). for the water to contain that much dissolved mineral content it seems like it might be continuously wetting concrete. When he said that I was thinking the water is not just running in around the top of the slab straight down around the column whenever it rains. Just a brief thought. But now you made me recall it.

Edited for dumb stuff.

 

[IanCA]

for the water to contain that much dissolved mineral content

Perhaps the runoff from the planters was more acidic than usual. If the salt and chlorine ion levels were higher?

Suggestions welcome.​

 

[zebraso]

Well that's a chemistry question. My head hurts as it is. The reactions involved were discussed earlier in this thread or the prior one. Not sure but acid from the planters (due to decay of organic matter or whatever is going on in the soil) would accelerate whatever is going on with the chlorides in the concrete dissolution. Some of the chemistry was posted previously. But whether it's carbonic acid or some other acid I don't think it matters. but between salt and organic planter decay in this environment I would guess the salt is a much larger factor. Unless those are acid loving plants and they are dumping it in. Wouldn't that be something? interesting question. Let's dump Miracle Grow Acid into the equation.

 

[MaudSTL]

On an unrelated topic, MDFR Deputy Fire Chief Jadallah conducted an investigation to determine the identity of the woman whose voice was heard in the garage. He has concluded it was that of the Live Nation Executive Theresa Velazquez, who had been visiting her parents in 304, rather than that of Valeria Barth from 204 as reported in USA Today. The report, which mentions spontaneous fires from EVs as previously discussed here, counters the USA Today claims that MDFR caused the garage fire and that the victim’s corpse was incinerated.

Here is the PDF of his report as provided by the local NBC affiliate in this story. The links within it don’t seem to work, but the embedded photos are there.

https://s3.documentcloud.org/docume...ntification-memo-4-25-22-with-attachments.pdf

I will update the spreadsheet, which lists the initial survivors of the collapse. Having occurred after the collapse, though, this has no effect on the timeline leading up to the collapse.

 

[FJBnomics]

Perhaps someone could do a drawing showing how the previous epoxy filled cracks in the low parts of slab that were leaking water, caused a larger water head to build after rain in the areas of the deflected slab. Say max deflection of slab is 3" at mid span, and with 9.5" slab, that means there is approximately 6" of potential water head in the structural slab, assuming .5" slope, for water to travel to crack at column.

I tried a toddler diagram but I could not keep the coloring between the lines.......

Clearly the water intrusion from planters was degrading concrete faster in deflected areas of slab, which is probably where epoxy injection was first performed to keep water out of garage, but creating a sorta artesian well effect around column 76?

Edit: But never emptying fully, thus leaving lots of water sitting in low area. So the top draining of water pond, lets sediments to fall to bottom of depression

 

[IanCA]

I would guess the salt is a much larger factor

Agreed, but don't forget the exhaust from the pool equipment room...

Suggestions welcome.​

 

[IanCA]

"weep holes in planters where practical"

My concern with that statement is the uncertainty. To quote Jeff Ostroff "If you don't tell the water exactly which route to take, it will take the most expensive".

Suggestions welcome.​

 

[FJBnomics]

Agree, constant pool of water and salts and chlorine from pool exhaust, leading to failure of slab at low points.

 

[SFCharlie]

I appreciated your photo because it was from a different angle. together they could give us 3d info.
Please remember the cars under the deck supporting it in odd ways.

SF Charlie
Eng-Tips.com Forum Policies

 

[SFCharlie]

Perhaps the runoff from the planters was more acidic than usual.

Please remember that 76 is not under the planters

SF Charlie
Eng-Tips.com Forum Policies

 

[Reverse_Bias]

I overlaid the displacement and cracks graphics from the Miami Herald. Cracks from the central puddle are leading to 4 different columns, including 76. Assuming the cracks somewhat resemble what is shown, the water would have a potential path.

 

[FJBnomics]

Excellent work, Reversebias.

Interesting to note the linear E-W crack in bottom of midspan depression, that lines up parallel between the column lines, thus the planar crack line that Zebraso was seeing in his Pixelizations......

The Planter roots could have made their own path for the water in the depression also...... after they clogged the drain lines in planters....