Sep 8, 2023 - News

New details emerge in Surfside condo collapse investigation

A concrete slab shows that the spacing of bars within it was wider than called for by design drawings. Photo: NIST

Construction around the pool deck of the Champlain Towers South condominium deviated from design requirements, federal investigators said Thursday.

Why it matters: A team from the National Institute of Standards and Technology (NIST) is in the process of determining why the building in Surfside, which opened in 1981, collapsed in June 2021, killing 98 people.

  • Investigators described preliminary findings during a live-streamed meeting.
  • They are still testing more than two dozen hypotheses.

Details: The investigation has largely focused on the condominium's pool deck and spots where horizontal concrete slabs met vertical columns.

  • In June, investigators announced that in the pool deck slab, reinforcing bars were installed lower in the concrete than required by design drawings.
  • Now, they've also found that the number of bars centered over vertical columns was inadequate. In one spot, four of 16 bars should have passed over a column, but only two did.
  • Bars were also spaced farther apart than the design required — commonly 20-40% wider, associate lead investigator Glenn Bell said, and the presentation showed.

Between the lines: Investigators have found no evidence of sinkholes.

What they're saying: Bell said the misplacement of slab reinforcements — along with shortcomings in the original structural design, loads added over time and potential corrosion of steel reinforcements — created "critically low margins of failure in the pool deck slab at the time of the building's collapse."

Of note: NIST found hard drives from the site that may contain video footage and is trying to rebuild seven of them.

  • It's also analyzing 1,700 documents, including residents' complaints about the building and photos of the garage beneath the pool deck.
  • And it's still looking into how construction of a neighboring building, 87 Park, may have affected the collapse.

What's next: The technical investigation should be complete by next June and a report with findings and recommendations issued in June 2025.

  • Investigators said additional video footage would greatly aid their work and urged the public to share anything they might have.

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