A Structural Engineer Explains How The Florida Condo Collapse Will Be Investigated

Authorities are promising an investigation to find out what caused the deadly partial collapse of a condo building in Surfside, Fla.

Independent investigators will look into it as well. One of them is John Pistorino, a longtime structural engineering consultant retained by an attorney to investigate this collapse. Pistorino has investigated similar situations around the country. He's not disclosing who has hired him as of now.

Pistorino designed the Miami-Dade County 40-year recertification requirement for buildings to be inspected after 40 years and every 10 years afterward. He came up with the program when he was consulting for the county after a Drug Enforcement Administration building collapsed in 1974 in Miami, killing seven and injuring 16.

Pistorino talked with NPR's Morning Edition about the investigation process and why a building needing repairs does not necessarily indicate it's in danger of collapsing. Here are excerpts, edited for length and clarity:

How does an investigation like this start?

Once the site is cleared and turned over, then an investigative group team made up of many different engineers and individuals will have an organizational meeting and decide how to go about taking out the evidence, if you will, and taking it maybe to a yard or a field someplace and try to reconstruct the building and look at the critical pieces to see if they can figure out how each piece failed and what the significance was.

And normally we would be taking samples of the strength of concrete, if steel is corroded, that type of thing, and have a laboratory analysis. And then down near the bottom, we would probably have a geotech engineering firm do borings underneath the building into the foundation areas in the piles and see what the condition of the soil in the foundation is at that time as well.

What are the questions at the front of your mind right now?

We have the 40-year recertification program that's been in effect for over 40, 45 years here in Dade County, which means that building owners are supposed to maintain their buildings from the time they're built. And the 40-year recertification is just a line in the sand to give the building officials some authority to say, if you haven't completed your investigation or your certification, you can issue violations or even withdraw occupancy of the building. So that system has worked very well. Many, many buildings have gone through it.

Structural engineers who are familiar with these kinds of buildings can go under and into buildings and look for telltale symptoms that reinforced concrete will show if it's being damaged or if there's settlement or some other condition going on and then make a decision as to whether or not it's significant.

But at any rate, whatever they find when they find it, it then needs to be repaired. And this should be going on from Day 1 when the buildings are built. They're not supposed to wait 40 years and then all of a sudden start looking around: What's wrong with my building? So the majority of the buildings here in South Florida have gone through that. And there are the 40-year-old buildings, there are some that have not yet that need to. But that's the safeguards we have.

In April, the condo board president told residents the building was in desperate disrepair. What does that bring to mind for you?

I can't comment on this particular building, but I will say that other buildings that I've been involved in where the repairs are significant ... if there's any kind of a potential life safety issue, the fact that repairs are necessary isn't really the issue. The building official has to be informed. And whether repairs are being made that have anything to do with the stability of the building or not, those type of repairs are ongoing on many buildings right now in South Florida, even at that level. But it's not necessarily having anything to do with the building itself being in jeopardy.

You designed Miami-Dade's 40-year recertification process back in the '70s. In a place like Florida where you have extreme heat, you have hurricanes, you have flooding, you have storm surges, why 40 years? Why not 10? Forty years seems like a long time.

The building that collapsed in 1974 was a building that was almost 40 years old, but it had not been taken care of. And in fact, some of the issues had been camouflaged. So we decided that at that time that 40 years, if a building is not being maintained, then it could become jeopardized.

At that time, I mean, even then, we had a lot of pushback. "Should it be 50 years or more?" So we got the 40 years. Our laws and our building code require the building be maintained as it was originally built at all times. So you start maintaining it. When you get to 40 years, an engineer who had been retained to look at the building should have no trouble going through it quickly if the building has been maintained as it was supposed to be.

Nina Kravinsky and Jill Craig produced and edited the audio interview. James Doubek produced for the web.

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