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I saw the report of construction defects in a NY Times article that I accessed via a tablet that gets behind the paywall. As I recall, experts surmised from photos and on scene viewing that rebar specified in the construction plans seemed to be lacking at one key point and otherwise of poor quality. The failure was supposedly in the connection between support columns and the horizontal slabs.

That is all too plausible. A lifelong Floridian, I saw the Miami-Dade construction boom of the 1980s on frequent visits there and as an attorney working in real estate development and then bank regulation. South Florida was newly awash in money from the drug trade, with lawyers, bankers, and businessmen busy finding ways to launder and invest the torrent of dirty cash. Real estate and construction were the venue of choice for doing so.

And yes, corruption was rampant and shoddy building practices were all too common. With liberal Democrat Miami-Dade then dominant in state politics, there was an air of lax standards and a wink and a nod toward misconduct in government and business.

Thanks. This has been a hot topic of discussion around the office and on our sites under construction. Not doubting that someone could have shorted the rebar, but that’s a lot less frequent than one might think on highrise construction. It’s not that there is more inspection (there is), but with a larger project, the amount of money that would yield is such a small percentage that there just isn’t much incentive.

The available photographs do show some corrosion in the bar and accompanying spalling in the concrete (the bar swells as it rusts and breaks the concrete cover), so that probably contributed.

The current favorite theory at work is that corrosion lead to a local failure at a column cap, and a punching shear failure on the pool deck. That lead to a progressive failure on the deck, and since that deck was tied in to the tower columns, those may have been pulled out of plumb, leading to the tower failure. That’s all conjecture from looking at the video and the plans, of course.

The good news is that NIST is on site. Those guys are serious nerds, and are not fully under control of the lawyers. They’ll figure out the things that lead to the failure, and put it in a very dense report with a lot of math. For sure this will lead to improvements in the next few code cycles, hopefully this terrible tragedy won’t be repeated.