Miami building collapse: ‘Failure point’ at bottom of condo could have led to crash, say experts

An investigation into what could be the deadliest accidental building collapse in US history has suggested that “a foundation-related matter” could be to blame for the tragedy.

Rescuers have been at the crumbled Champlain Towers South in Surfside, Florida, since the early hours of Friday, when the 12-story residential block collapsed, so far claiming the lives of nine individuals.

A further 150 are thought to be unaccounted for in what President Joe Biden described on Sunday as an “enduring tragedy” for the community of Surfside and Miami-Dade, Florida.

CCTV footage appears to show the building falling in stages, with the centre of Champlain Towers folding-in on itself before an eastern section also collapses.

A number of experts told The New York Times that a structural failure could have been the cause of the incident, and that it appeared to be at the foundation of Champlain Towers South, which was constructed in 1981.

“It does appear to start either at or very near the bottom of the structure,” said Donald O. Dusenberry, a consulting engineer with 45 years of experience investigating structural collapses. “It’s not like there’s a failure high and it pancaked down.”

“[It] would suggest a foundation-related matter – potentially corrosion or other damage at a lower level,” Mr Dusenberry told the Times, adding that “you certainly can’t rule out a design or construction error that has survived for 40 years.”

The collapse of Champlain Towers South has caused concerns for the dozens of apartment blocks in Surfside and Miami-Dade, which have stood for decades facing the Atlantic Ocean, and it’s salty air.

An investigation in 2018 found that “failed waterproofing” of the pool area at Champlain Towers was “causing major structural damage to the concrete structural slab below these areas”, the Associated Press reported.

The findings, released in recent days by the city of Surfside, added that “failure to replaced the waterproofing in the near future will cause the extent of the concrete deterioration to expand exponentially”, and warned of “major structural damage”.

Mr Dusnberry told the Times that the corrosion and structural issues identified by the 2018 investigation could be significant it was found near to the tower’s supporting columns. Repairs were expected at the building before the incident on Friday.

It will take weeks for an official investigation to conclude what was the exact cause of the collapse at the 12-story block. For now, the rescue effort is continuing.