Miami Beach, Champlain Towers South apartment building collapse, Part 10 79

[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


SF Charlie
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[rodface]

Update on the rendering. I have

-Modeled the PH level columns and glazing
-Completed glazing of East facade
-Took a shot at the lighting
-Adjusted camera (@Santos81 thanks for the coordinates), still just eyeballing it but feels very close now

Full-res attachment:
Link

 

[AusG]

Impressive. It shows the skyline of the first-collapsing area as noticebly darker and harder to see than the eastern section. I think this poorer illumination may have contributed to an impression of missing components.

 

[Santos81]

Not too shabby there rodface. If it helps, the camera has a 108° FoV and focal length of 127’

 

[Santos81]

It’s a start…

Whether it’s worth investing much time on is questionable

 

[rodface]

(Applause) now *that* looks right.

I’m definitely only going as far as needed to provide the “initial frame” of the CCTV. I probably won’t bother with floor 1, the garage, the pool deck and beams, etc... all of which your model is clearly incorporating. Not to mention the columns and interiors etc.

I did have a go at modeling the cooling tower and ducting, 100% eyeballed with no accurate dimensioning (LOL). But as it turns out it’s completely obscured from the camera angle.

I *am* putting effort into getting the windows just right, they help make sense of the mush. Already I think I can better identify where exactly the collapse is happening.

 

[SFCharlie]

Update on the rendering.

I'm stunned, It's looking really great.
Thanks very much!


SF Charlie
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[SFCharlie]

It’s a start…

It’s a great start…
..and, yes I know it's a lot of work...
Thanks very much!

SF Charlie
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[gonefishing2]

Take Away: Building was designed for a nominal 20 year life without major upgrades and constant expensive maintenance and repairs........ It was designed to flip for quick profit!

[highlight #FCE94F]"Building collapse in Miami: Multiple factors could have contributed, experts say
By nytimespost - June 26, 2021"[/highlight]

[highlight #FCE94F]"Two engineers who reviewed a surveillance video of the collapse in slow motion said it appears the upper part of the building’s middle section collapsed before the lower part.[/highlight]

If the collapse had begun with the foundation, geotechnical engineering professor Steven Kramer of the University of Washington in Seattle would have expected to see everything going together. [highlight #FCE94F]Instead, he said, the top several stories appear to fall first.[/highlight]

[highlight #FCE94F]A clue was when dust first appeared in the image.[/highlight]

“The view [in the surveillance video] of the base of the building is obscured by the trees, but I think that dust would have appeared above the trees earlier if the failure had started [at the base],” he said.

Michael Chajes, a professor of civil and environmental engineering at the University of Delaware who does structural forensics, agreed.

[highlight #FCE94F]“If a lot of things were breaking lower down you would have seen the dust below,” he said.[/highlight]

[highlight #FCE94F]Another clue came in how the building fell almost straight down.[/highlight]

[highlight #FCE94F]“When the bottom gives out, unless it gave out uniformly, you would have a lot of twisting and leaning,” Kramer said. “If one of four columns goes at the base, the thing would tend to list to the side.”[/highlight]

[highlight #FCE94F]The video shows that as the central section began to fall, the eastern section twisted toward it a little before the center collapsed. The eastern part remained standing for another 20 seconds or so before it too began to collapse.[/highlight] In that instance, Kramer believes debris from the center smashed into support beams for the eastern section, rendering it structurally unstable.

On this point experts did all agree: It will take a long time to discern exactly how and why Champlain Tower South collapsed and that, once the answers are known, they’re likely to prompt changes to the building industry."

[highlight #FCE94F]“The whole regulatory apparatus is behind the times, relative to current risks,” s[/highlight]aid Clinton Andrews, a professor of urban planning and director of the Center for Green Building at Rutgers University. “I think the case in Florida illustrates that problem.”

[highlight #FCE94F]"Ashraf, the structural engineering consultant and author of “Practical Design of Reinforced Concrete Buildings,” took note of residents’ complaints that their building was shaking because of nearby construction.[/highlight] He was recently called in to fortify an ocean-facing residential building on Miami’s Brickell Avenue. Like Champlain Towers South, there is construction near the Brickell building.

[highlight #FCE94F]“Those vibrations are a lot of forces on the building, for which it is not designed,” said Ashraf, who decided to lay out a temporary reinforcement plan. “We tested the concrete and we shored it up. We took steel rods and braced the building. Once construction is over, we’re going to retrofit the building with carbon fiber wrapper or steel plates.”[/highlight]

"Ashraf says a similar plan should have been devised for Champlain Towers South."

[highlight #FCE94F]“This is not a design failure. This is a maintenance issue,”[/highlight] he said. “If those things are not addressed, these kinds of tragic things can happen.”

[highlight #FCE94F]"In the end, most of the experts agreed, it’s rarely a single thing that causes a building to collapse."[/highlight]

[highlight #FCE94F]“It’s almost always a series of things that build up,” said John Wallace, a professor of structural engineering at the University of California, Los Angeles who has participated in multiple forensic analyses of building failures. “Each item adds additional demands upon the building. These things cascade and then it reaches a tipping point where there is this type of collapse.”[/highlight]

"Englehardt, the University of Miami professor, agreed. "

“When incidents do occur it’s because of a series of preceding failures, so there had to be more than one cause for this,” he said. [highlight #FCE94F]“It had to be a series of sequential failures that would result in anything like this.”[/highlight]

https://www.nytimespost.com/buildin...e-factors-could-have-contributed-experts-say/

 

[Js5180]

SF Charlie,

I can’t argue with that - it has clearly moved between 28 and 33.

Looking at the video, it also appears to be present in frame 1, but not on your version of frame one:

Source is:

https://m.youtube.com/watch?v=KR29pLccutY

Any agreement/disagreement?

 

[Santos81]

Applause) now *that* looks right.

I’m definitely only going as far as needed to provide the “initial frame” of the CCTV. I probably won’t bother with floor 1, the garage, the pool deck and beams, etc... all of which your model is clearly incorporating. Not to mention the columns and interiors etc.

I did have a go at modeling the cooling tower and ducting, 100% eyeballed with no accurate dimensioning (LOL). But as it turns out it’s completely obscured from the camera angle.

I *am* putting effort into getting the windows just right, they help make sense of the mush. Already I think I can better identify where exactly the collapse is happening.

It is a bit over the top but was not really intended for this purpose. There’s an absurd amount of data in the model which helps for accuracy; just makes it very slow to render despite hiding 80ish percent. I wanted to focus on the lighting for now as it provides the most clues to work with. Windows, doors, and hurricane shutters are very important.

HVAC models as delivered to job per spec were provided by the manufacturer.

It is a bit fruitless though as the collapse is already quite far along; everything east of Shear Wall 1 is in motion and no longer in the position it was just prior to the beginning of the failure. The distortion on the right side is not caused by the lens.

Instead of seeking proof that the roof was the cause, examine how it may have been the key to the collapse NOT occurring sooner.

 

[Js5180]

All About Money,

The comment about the dust makes a lot of sense - the area of the “missing parapet” could be interpreted as a dust cloud.

 

[SFCharlie]

Looking at the video, it also appears to be present in frame 1

I can't see what you are referring to, so, sorry for my old tired eyes.

SF Charlie
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[SFCharlie]

Thank you for calling our attention to the nytimespost - June 26, 2021 Article

Two engineers who reviewed a surveillance video of the collapse in slow motion said it appears the upper part of the building’s middle section collapsed before the lower part.
If the collapse had begun with the foundation, geotechnical engineering professor Steven Kramer of the University of Washington in Seattle would have expected to see everything going together. Instead, he said, the top several stories appear to fall first.
A clue was when dust first appeared in the image.
“The view [in the surveillance video] of the base of the building is obscured by the trees, but I think that dust would have appeared above the trees earlier if the failure had started [at the base],” he said.

We have had a lot more time to round up more evidence. The witness interview contradict middle floors first.

As for dust, trying to separate dust from camera and compression artifacts (fuzziness etc.) requires more that just viewing the video in slo-mo IMHO.

SF Charlie
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[Santos81]

As for dust, trying to separate dust from camera and compression artifacts (fuzziness etc.) requires more that just viewing the video in slo-mo IMHO

The on-shore wind wasn’t light that evening either which would have forced most of the initial dust into the now windward open garage and exit through the ventilation shafts and any vertical chase not sealed; for instance the elevator shaft. Now where does that exit again? Hmmm…

 

[rodface]

Created this mainly to scratch a mental itch. Attempting to replicate the appearance of CCTV frame 1.

The model cannot actually be distorted so this was done in Photoshop.
The central section has been moved downwards by about 1 floor. No attempt made to render the interface between sections; just treated it as an (unrealistic) clean slice.
Lights have been added to aid positioning.
I have not added/shown the interior/rear of building which appears to be visible behind descending central section.

All based upon my amateur observations.

 

[Demented]

The on-shore wind wasn’t light that evening either which would have forced most of the initial dust into the now windward open garage and exit through the ventilation shafts and any vertical chase not sealed; for instance the elevator shaft. Now where does that exit again? Hmmm…

It was gusting what, 30mph on and off? Everything would have been pretty water soaked too which would have minimized dust as well, especially from the deck collapse.

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

 

[ianskman]

Hi everyone Ive run to pictures through some software, Look at the column with yellow paint..now about 40 percent from the bottom of the beam look through each gap in the gate from left to right the top side of the beam is visible for about 8 gaps at the 7th gap the underside of the beam is visible, there is also at the top of the first gap in the bars there seems to be an angle to the column at the top.I believe its possible that the base of column m 10 has its corners hidden by the bars in the last image and the top part is missing.

 

[Jedidad]

Thank you for calling our attention to the nytimespost - June 26, 2021 Article

I never heard of the "New York Times Post" before. I go to that link and only see 3 paragraphs. It looks like they're just reposting an article from USA Today: Link

You need a subscription to view that article.

 

[gonefishing2]

Take Away: [highlight #FCE94F] Miami-Dade has a conflict of interest investigating Champlain Collapse due allowing the apparent irresponsible building of 87 Park adjacent to Champlain, with for example, damaging pile/construction vibrations as close as 10 feet from Champlain garage wall.[/highlight] Miami-Dade should have required vibration monitoring equipment be installed on adjacent buildings, by independent testing agent, to monitor and thus ensure pile driving/construction vibrations had no adverse effects to adjacent buildings. Surfside should have stepped in once notified of problem, and assisted Condo Association in legal action to require responsible construction techniques.

Excerpt from Structural Damage from Adjacent Construction Projects – Expert Article from Robson Forensic website, link below:
There are several ways that harmful vibration levels due to construction activities can cause damage to neighboring properties and structures. The most common include; damage to a structure directly from the energy of the vibration source, resonant structure response (i.e. the natural frequency of the building and soil matches the frequency of the ground movement causing uncontrollable shaking) and/or the densification of soils supporting a building structure resulting in settlement. All these vibrational effects can result in cosmetic damage and/or irreparable structural damage.

Vibration can occur from numerous construction activities, including:

Blasting
Pile driving
Compaction / dynamic compaction
Jackhammering / chiseling
Vibrofloatation
Pavement breakers
Demolition
Trenching activities
Heavy vehicle traffic
If construction activities which include potentially damaging vibration are scheduled to occur on a specific job site, it is imperative that one or all of the suggested measures below be implemented:

A well-planned due-diligence investigation and project coordination of neighboring properties. An example would be to determine if a neighboring facility has sensitive electronic, instrumentation or imaging equipment such as an MRI that may be disrupted by construction related vibration activities.
A pre-construction survey of all adjoining structures
A geotechnical report that clearly identifies the underlying soil strata and geologic conditions
Specifications for the control of construction vibrations
Pre-planning to avoid potential vibration damage by selection of alternate construction equipment. For example, auguring/pre-drilling piles as opposed to pile driving.
Construction logs of equipment and approximate time frames of construction
Vibration monitoring by a licensed testing agency
Building movement monitoring of neighboring structures by a licensed testing agency
Prior to construction activity, it can be desirable to establish a benchmark, especially if there is pre-existing damage such as settlement or structural deficiencies to neighboring structures. This particularly holds true if the building is older and would have a tendency for a lower tolerance of vibration induced damage.

Furthermore, forensic studies following a claimed damage event, to determine if a building was damaged by neighboring construction vibrations, should include knowledge of the geological conditions, where the vibration producing activity took place on the construction site, if there were any monitoring devices, and whether there were pre-construction surveys that could be evaluated as a bench mark for pre-existing damage. Therefore, it is imperative to document the location and type of construction activities which occur relative to the potential damage.

https://www.robsonforensic.com/articles/structural-damage-vibration-adjacent-construction-expert

 

[gonefishing2]

NY Post Article with source from USA Today and Palm Beach Post opened full article on iphone and Google Chrome on Mac. Did not open full article in Safari on Mac, so could be ad blocking software or privacy settings causing problems