[brudgers]

See all that fairly fresh paint?

In the first picture they painted over failed concrete. The pictures are said to be “typical.”

The reasons it wasn’t evacuated at the time were business and politics not comprehensive structural investigation.

You see if the client isn’t paying to find problems below the surface, then they won’t be found. And it is common for clients to not want to find such problems. And for engineers to limit their analysis accordingly.

I know what my professional opinion would have been based on those pictures. It would not have been good for my business given the client profile.

Or to put it another way, those pictures show that what happened had a real chance of happening. That’s not hindsight. It would have caused me grave concerns.

[MertsA]

Yeah that's some pretty widespread spalling on the garage deck. Regardless of what went wrong, I'd be surprised if rust jacking or just plain section loss of the rebar wasn't a principle factor behind the collapse. All of that rebar has just been rusting for an additional 3 years since those photos were taken and it looks like the corrosion was already pretty spread out at the time and no one did anything to address it.

Tyler Ley has dozens of videos on the topic, I know I've seen a great overview of concrete deterioration but he's got so many videos I can't find it. Here's a intro to concrete corrosion though that explains some of it.

https://www.youtube.com/watch?v=mOCJFCaXN0s

[secabeen]

Thanks to both of you; this is better analysis than I've seen in other forums.

[brudgers]

Conversely, your response to my initial comment was internet ordinary.