The collapsed building in Miami featured a “very subtle” collapse in the 1990s.

A study carried out in 2020 found that the Surfside building who collapsed this Thursday recorded a “very subtle” shipwreck in the 1990s. Last year’s assessment found that the building had sagged slightly in the 1990s, at a rate of about 2 millimeters per year between 1993 and 1999.

We knew that the roof of the building was being renovated, in accordance with county laws which require it every 40 years. The authorities ruled out that this work could have caused the disaster.

The 2020 report

One of the study’s authors, Shimon Wdowinski, a professor at Florida International University, told the CNN What he didn’t know “if the collapse was foreseeable”. “By your own, sinking would not cause a building to collapse “the institution explained in a statement paraphrasing the researcher.

It is not known whether city officials were alerted to the sinking before the collapse. “We didn’t give it too much importance,” he said. “But in this case, the sign of sagging is very localized in this building. This means that it is not necessarily the building that collapsed. It could be that the building collapses on itself, if there was structural damage to the building “, he explained on Friday to CNN.

the land subsidence measured in Miami is much slower than in other parts of the world also studied by Wdowinski, like Mexico City, which sinks 38.1 centimeters per year, nearly 2,000 times faster, according to the statement.

But a few millimeters, “added up over many years, are a large number”, said Matthys Levy, professor of engineering at Columbia University, as quoted by USA Today.

When part of the building collapses, it usually creates a chain reaction, as in the September 11 attacks, he explained. “It doesn’t stop, it’s unstoppable. (…) There is nothing in the structure strong enough to contain the collapse “Levy said, referring to a “cascade” mechanism.

Some media in the United States have reported that a building owner filed a complaint in 2015 that an exterior wall was affected by cracks and water damage.

For now, the investigation into the causes of the tragedy is progressing and it is not known how long it could take. Experts believe that this is a process that “it takes time“And that it will not be completed in a few” days “or” weeks. “

Gradual collapse

A structural engineer Florida brews several hypotheses on the causes of “gradual collapse“From the building that collapsed on Thursday in the county of Miami-Dade, what’s left at least 4 dead and 159 missing as rescue teams continue their desperate search through the rubble.

Authorities remain vigilant in search of survivors after collapse Partial this morning from the building Champlain Tours South, 12 storeys, in the small town of Surfside, adjacent to Miami Beach. The ocean-view building collapsed in seconds and 55 of its 136 units were reduced to rubble..

(With information from AFP)

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