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Miami Beach, Champlain Towers South apartment building collapse, Part 14 41

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SFCharlie

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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

SF Charlie
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"The construction of a new luxury condo tower just feet away from Champlain Towers South caused severe damage to the fragile, poorly designed building in Surfside, eventually leading to the collapse that ..."

In their own words they damn themselves. Well designed and built structures, even averagely designed and built structures cope with adjacent construction. City buildings are always "just feet" away from something else. They go on to claim the building needed only "routine" repairs and maintenance. $15 million worth of routine to head off structural deterioration becoming exponential according to their own engineer? Blaming a building finished in 2019 for years of water incursion and damage noted in a report from 2018?

I feel this case is structurally unsound, and its collapse will not need 14 threads of investigation to understand.
 
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In paragraph 108 of that document, the perspective looks VERY wrong. The CTS pool looks way too small. It's as if the foreground construction area is many floors up in the air.


spsalso
 
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Costruction_next_to_Champlain_Towers_South_Zoomed_in_ftvusu.jpg

Costruction_next_to_Champlain_Towers_South_from_pdf_rcgcci.png

Costruction_next_to_Champlain_Towers_South_December_2017_n7y1yi.jpg
 
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In the building Integrity video, the quotes from the lawsuit mention a rule-of-thumb for vibration damage around 0.5 in/sec and state that this was exceeded many times. I think this is a reference to this diagram:
chart_h6oym7.jpg

...that I found here:
Above the line is unsafe, below the line is not, although local conditions and investigations prevail above all. Note the velocity "safe" limit increases with frequency. Note also that the damage referred to is to wall plasters, not to fundamental structure.
I learned a lot about sheet pile driving from this document:
It suggested to me that both the operating frequency of pile driving equipment (around 40-50 hz), and the resonant frequency of the example soils in the paper (15-26 hz) are higher than that part of the limit-line where 0.5-0.75 inches/second pertain (4 - 11 hz). Vibrations at >0.5 inches/sec at those higher frequencies could be staying mostly in the safe zone, leaving maybe some minor surface damage predictable.

To shorten a long story, the complainants will have to prove that the excessive vibrations were occurring in a portion of this chart relevant to structural damage, as well as as dealing with the other issues of why it took so long to express itself and why it was not mentioned by Morabito. It will be interesting to see this play out.
 
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Would repair mortar technically be a plaster? We know there was a lot of that on CTS, specifically on the underside of the deck/parking level ceiling near the zones they're claiming had accelerated deterioration. I need to go back through the contractor botes but if I recall correctly, portions of the repair zones with mortar repair versus caat in place bagged concrete varied from .75" to 3" in overhead areas where rebar was exposed previously. Still unsure exactly how much and where without the asbuilts. Differential settlement may have occured, but if the data from FIU is accurate, CTS was already suffering settlement, likely uneven, for most of it's life and one could easily argue the pile driving had nothing to do with that.

The damage to the wall from the excavator(s) to me is more of an issue than the vibrations from pile driving, especially if it was allowing water to flow more easily between the parimeter wall and retaining wall. These sections are the only points of the parimeter wall that show any true signs of failure around thr entire property. The walkpath being below grade and sloped towards the CTS property wouldn't have helped any in those damaged areas.
 
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Demented said:
Would repair mortar technically be a plaster? We know there was a lot of that on CTS, specifically on the underside of the deck/parking level ceiling near the zones they're claiming had accelerated deterioration.
Click to expand...

If they performed repair work the 'right' way, no- they would not use cement plaster, and would definitely not use gypsum plaster.

Concrete repair compounds are specialized, and when properly applied they restore physical properties of the assembly. Plaster compounds do not.

Now, given the history of this building, that isn't to say that any repair work was executed correctly. I wouldn't be surprised to learn that exposed rebar due to spalling or whatever other damage had been 'fixed' by covering it with plaster.
 
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Per the work permits.

sika quick 100. Portland cement repair mortar
Quarts 50-70%
Cement 10-20%
Calcium Sulfate 1-5%
Aluminum Oxide 1-5%

28 day values
2.5kpsi slant shear strength
400psi splitting tensile strength
1kpsi flexural strength
300psi tensile adhesion strength


Sika repair SHB Portland cement repair mortar
30-50% Cement
30-50% silicon dioxide
10-20% Quarts

28 day values
1kpsi Slant shear
800psi Flexural
300psi Ttensile adhesion strength


SikaRepair 222

25-50% Portland cement
50-75% Quarts

28 day values
2kpsi slant shear
750psi Flexural
450psi Splitting Tensile
2kpsi Tensile adhesion

Edit:
This was for all horizontal, vertical, and overhead repair, including repairing all exposed rebar. Much of which was to the lower portion of the deck/parking ceiling, but was also used to repair spalling on the edges and bottom side of balconies end columns. Pourable concrete was saved for larger areas of partial and full depth slab repair in the balconies and into the interior of 211.

Edit 2:
Omitted because I felt it wasn't relative, but 28 day compression of all the above is 6k to 7kpsi
 
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Demented said:
Would repair mortar technically be a plaster
Click to expand...

SwinnyGG said:
I wouldn't be surprised to learn that exposed rebar due to spalling or whatever other damage had been 'fixed' by covering it with plaster.
Click to expand...

As a rehabber of historic residences, in my experience there is no resemblance between plaster and mortar. I have used mortar to fill exterior gaps subject to water exposure/intrusion, and plaster to coat/finish interior surfaces that are not subject to exposure to water. For concrete ceilings subject to moisture, plaster would bubble, soften, and fall down almost immediately. There are concrete repair compounds, often used with epoxies, made specifically for this scenario.
 
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I drove to the NIST secret site where they are storing all the Champlain Towers south debris and did a live stream today, showing the debris piles, the rebar piles, the columns laid out, and the crushed garage cars.

I also later got much better photos with my Nikon, photos and video coming, closeups of the crushed cars all removed from the garage.

More photos that Kai keeps claiming I steal from here, when in fact I am a major contributor of photos here.

In fact, Kai came here and stole the photos I posted of the walk-around on the condo collapse site, the photos near the H-Beam, and the photo with Allyn Killshceimer in it. And he accuses everyone else of stealing. Nothing worse than a lying hypocrite thief. He would break into your house and sue you for the gas to get over there.
 
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@MaudSTL
Poor phrasing on my part again. I really need to wait until I've had my 2nd pot of coffee before posting.

What I meant was in regards to adhesion properties and durability through the vibrations. But yes, I agree that there's only a snowball's chance in hell that plaster of paris was used on the exterior in the structural repairs.

Precision guess work based on information provided by those of questionable knowledge
 
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Spartan5 said:
Does anyone know how to unsubscribe from the YouTube drama?
Click to expand...

Relax said the Nukeman,​
We are, programed to receive...​
You can unsubscribe any time you like,​
But you can never leave...​

Sig lines are for trolls.
 
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nist_storage_site_thumnail_lz78gd.jpg


Here is a photo I shot yesterday at the NIST investigation and storage site for the Champlain Towers Condo collapse debris and cars. They had many of the crushed vehicles from the garage there in the NIST lot.

If you look at the 2 crumpled vehicles to the left of the main vehicle in my photo here, you will see these appear to be the tar kettles from the roofing company. I read reports from annoyed Champlain Towers South residents about the noise from the roofs drilling into the roof for the new window washer anchors. if I remember correctly, these vehicles were brought into the Champlain Towers parking garage every night for storage.
 
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It's already been determined that they were parked in the maintenance spots on the side of 88th and not on the roof or in the parking garage

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