Parking Garage Construction Collapses in Miami

This just happened this morning. As an EE would like to hear what CEs think caused this "pancake collapse".

http://www.huffingtonpost.com/2012/10/10/parking-garage-collapse-miami-dade-college_n_1954851.html

I don't want to speculate too much, but precast parking garages are designed and built to be constructed easily and fairly quickly. The way they do this is to make them simple spans with L-shaped spandrel beams and upside T-shaped interior beams like this pic:



Then they place the double T beams (or whatever beam and slab system they are using) on these girders. This means that there is very little redundancy and if one piece fails, you typically see multiple parts fail. Due to the large amount of destruction of this collapse, it wouldn't surprise me if something happened to one of the columns of the structure, but there's really no way to know. I just hate that it happened and I hope that there are minimal injuries and deaths from it.

Edit: Posted this in the wrong thread.

First and foremost, I hope that those individuals that are still unaccounted for to be found safely and unharmed. I also hope for a speedy recovery to those injured.

Now, looking at the video and the pictures, it appears to be a post tensioned slab sitting on the main beams. It may be possible that since it was still under construction, that the cables had not yet been installed and some movement occured at one of the column lines; allowing the top most section to fall and start the domino effect. These cables really tie things together since the members are not joined by any other means than by friction & gravity (from the few that I've walked through).

I won't speculate much beyond this due to the fact that I'm not on scene and cannot view it any better than the few pictures that are available online. Pictures don't tell the whole story.

I heard about this yesterday but never actually read about it until this morning.

I would agree with Ble, there was most likely a failure at a support (or support connection).

It is a sad situation.

Agreed. The redundancy in the system comes with the topping slabs being poured, but in the pic above that doesn't appear to have happened yet. A co-worker was working on a 10-story parking structure several years back out on the west coast and the PM said they had to essentially finish the bottom 5 floors before they could go higher as an added precaution against earthquakes. He said the columns deflected several inches by the time they got to the top because they were post-tensioning as they went up.

My prayers go out to all of the people involved...

but what's all this mean for the engineer with his stamp on the plans?

Not being a civil guy (no pun intended in this case...) my assumptions are that the design of a structure such as this is heavily regulated with standards and codes like many other industries. As long as the code is well referenced and the final design is consistant with industry practice, the engineer has performed his "due diligence" for the design.(note: extremely simplified statement)

My questions: Is the PE responsible for the execution of those plans? If yes, to what extent and how does he/she ensure the plans are followed? If no, who is?

Please educate me.

Engineer is typically responsible for the constructibility (you have to be able to build it) and final product. If the contractor is a moron and builds it wrong, it's the contractor's fault.

Think of it this way: If the tire falls off of your car, whose fault is it? If it was assembled properly and it just broke, then it's the manufacturer. However, if you didn't put the lug nuts on, then you're the dumbass.

what isf hes a dubmbass and puts a ll the lugntus on in the firts place?

Well, then he shouldnt be driving because he's drunk...

Thanks guys! This is kinda what I thought. Don't get drunk before you put lugnuts on because you'll be a dumb ass but if you're a guy like me, that doesn't have to put lug nuts on, go get drunk and blame the missed deadline on sales misinformation, poor quality from china, and late test results!!

Cheers!!

Lumber Jim said:

Thanks guys! This is kinda what I thought. Don't get drunk before you put lugnuts on because you'll be a dumb ass but if you're a guy like me, that doesn't have to put lug nuts on, go get drunk and blame the missed deadline on sales misinformation, poor quality from china, and late test results!!

Click to expand...

You forgot the true culprit.

George W. Bush.

^^^ that's implied.

so.. why were they constructing a garage with lug nuts? Was that how it was shown on the design drawings?

I thought the culprit was that Obama was a secret muslim?