A federal probe into the June 2021 collapse of a Surfside condo tower that left 98 people dead continues to point to the building’s pool deck as the most likely initiation point of the collapse, investigators said Thursday at a meeting in Maryland.
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The land that once housed Champlain Towers South at 8777 Collins Avenue is pictured June 3, 2022. The condo tower partially collapsed on June 24, 2021, killing 98 people. |
They have also been
analyzing several videos to better understand the collapse
sequence, including a video taken by a tourist on the night
of the collapse that showed water gushing into the garage
and chunks of concrete covering the floor on the north side
of the building.
Investigators said they worked with the FBI to enhance the
video, which helps prove that the pool deck collapsed into
the parking garage before the east portion of the tower
collapsed.
A draft report of the investigation is still more than a
year away, anticipated in May 2025. A final report is
expected in September 2025.
In June 2022, investigators said they hoped to release a
final report by 2024. On Thursday, they said difficulties in
securing contracts and challenges in testing procedures have
led to delays.
Pablo Langesfeld, whose 26-year-old daughter Nicole died in
the collapse, expressed frustration about the pace of the
investigation during a public comment period.
“I’m deeply disappointed by the prolonged delay in
determining why the building collapsed,” he said. “I
understand the complexities of such an investigation, but
almost three years later, 40 [investigators] and around $30
million spent and still no solid answers — it is not
acceptable.”
The ultimate findings will have implications for millions of
high-rise dwellers around the world, with recommendations on
changes to building codes and construction practices that
could prevent a similar catastrophe from happening
elsewhere.
“We want our investigation of this failure to have lasting
impact,” said Judith Mitrani-Reiser, the lead investigator
on the NIST investigation and a Miami native. “We want it to
save lives, and we want it to ensure this never happens
again.”
The findings so far echo a Miami Herald investigation, which
found that the pool deck collapsed several minutes before
half of the tower fell. In consultation with structural
engineers, the Herald identified major weaknesses in the
structure and other problems that compounded in the weeks
before the collapse. Those included areas where the pool
deck appeared to be sagging dangerously, cracking a nearby
planter.
Investigators said that among the “most probable” initiation
points were failures in slab-column connections in the pool
deck that caused the slab around the columns to drop.
“Knocking noises” heard by some residents before the
collapse bolster the notion that steel reinforcements had
fractured at those connection points.
Another possibility being considered is that the failure of
columns at the tower’s southern edge is what triggered the
collapse of the pool deck and then the tower. Investigators
said they found significant degradation at the bottom of
some of those columns, caused in part by flooding in the
parking garage.
In a presentation last June, investigators said the
40-year-old building’s pool deck had “critically low margins
against failure” because of pervasive weaknesses in the
structural design that were exacerbated by misplacement and
corrosion of the reinforcing steel within the deck, as well
as the addition of planters and heavy pavers that were not
accounted for in the original designs.
While the team of dozens of engineers and other experts is
considering about two dozen failure hypotheses, it is
seeking to rule out possibilities that appear less likely.
That includes underground factors like a sinkhole in the
limestone underneath the tower or uneven settlement of the
building’s foundation. Investigators said Thursday there is
“very low probability” that those factors contributed to the
collapse.
The probe has found no evidence of an explosion or other
extraordinary event that could have triggered the incident.
Investigators have yet to determine how the pool deck
collapse may have caused the tower to fall minutes later.
But computer simulations performed by researchers at the
University of Washington in collaboration with the Herald
showed that when the deck fell and disconnected from a
perimeter wall at the south end of the pool, damage would
have spread into the tower along the ground floor near the
gym at the center of the L-shaped structure.
Experts who consulted on the Herald’s forensic investigation said the preliminary deck collapse would have strained the columns along half of the tower’s perimeter, causing them to fracture and ultimately collapse inward along with the majority of the tower.