The death toll of the collapsed apartment building in Florida has risen to nine as crews continue to sift through the rubble.
More than 150 people have been declared missing since Champlain Towers South fell to the ground on Thursday (local time), with teams from Israel and experts from Mexico joining the search.
Search crews are also using dogs, sonar, drones and infrared scanning to find survivors.
"Everybody that is needed is on the site and doing the work and we're continuing our efforts to find people alive," Miami-Dade County Mayor Daniella Levine Cava told CBS on Sunday.
Officials still have hope some of the 156 people who are unaccounted for may still be alive.
"The biggest thing now is hope," Fire Chief Alan Cominsky said.
"That's what's driving us. It's an extremely difficult situation."
Some families of those missing have provided DNA samples to officials while others recounted narrow escapes. Police released the names of four victims who ranged in age from 54 to 83.
Champlain Towers South resident Erick de Moura was supposed to be home when the building collapsed, but his girlfriend persuaded him to spend the night at her place less than three kilometres away in Miami Beach, likely saving his life.
"Only by God. To me this is a miracle," the 40-year-old Brazil native told Reuters.
Building needed $12 million worth of repairs years ago
An engineering firm estimated nearly three years ago, the Champlain Towers South building needed repairs costing more than US$9 million (about A$12 million) were needed.
The email from the firm of Morabito Consultants was among a series of documents released by the city of Surfside as rescue efforts continued.
The release of the 2018 cost estimate followed the earlier publication of another document from the firm showing the ground-floor pool deck of the building was resting on a concrete slab that had “major structural damage” and needed to be extensively repaired.
That report also uncovered “abundant cracking and spalling” of concrete columns, beams and walls in the parking garage.
The report did not warn of imminent danger from the damage, and it is unclear if any of the damage observed was responsible for the collapse of Champlain Towers South.
The cost estimate showed repairs across the entire building would cost more than US$9.1 million dollars (about A$12 million), with the cost of work at the garage, entrance and pool deck alone accounting for more than US$3.8 million (more than A$5 million).
The work had not been done by the time the building collapsed.
The earlier report said the waterproofing under the pool deck had failed and had been improperly laid flat instead of sloped, preventing water from draining off.
“The failed waterproofing is causing major structural damage to the concrete structural slab below these areas. Failure to replaced the waterproofing in the near future will cause the extent of the concrete deterioration to expand exponentially,” the report said.
The firm recommended the damaged slabs be replaced in what would be a major repair.
Some of the damage to the concrete in the parking garage was minor, while other columns had exposed and deteriorating rebar.
It also noted many of the building’s previous attempts to fix the columns and other damage with epoxy were marred by poor workmanship and were failing.
Beneath the pool deck “where the slab had been epoxy-injected, new cracks were radiating from the originally repaired cracks”, the report said.
These were all problems that should have been dealt with quickly, Gregg Schlesinger, an attorney specialising in construction defects and a former construction project engineer, said.
“The building speaks to us. It is telling us we have a serious problem,” Mr Schlesinger told The Associated Press.
“They (building managers) kicked the can down the road. The maintenance was improper. These were all red flags that needed to be addressed. They weren’t.”
The firm, Morabito Consultants, said it was hired again in June 2020 by Champlain Towers South to begin the 40-year recertification process that would detail what work needed to be done.
“At the time of the building collapse, roof repairs were under way, but concrete restoration had not yet begun,” the statement said.
The building was in the midst of its 40-year recertification process, which requires detailed structural and electrical inspections.
In an interview on Friday, Surfside Mayor Charles Burkett said he wasn’t sure if the inspection had been completed, but he said it may contain vital clues.
With Reuters and Associated Press
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