Exactly the same type of accident happened in Auckland here, about two weeks ago, although on a slightly smaller scale.
Same type of building construction too.
What annoys me, is this, at the time of the collapse over here, the building crew were using a concrete(cement) pump to fill the floor in, 3 floors up(how this is done I'm not really sure!), half way through the pour, the 3rd and 2nd floors collapsed.
Luckily there was no one else in the building at the time, those that were, got off with a few broken arms, etc.
To add a second layer of concrete(which has wieght) to an already heavy floor is just lunacy.
I most certainly agree with your comments about modern building construction.
And the majority of Architects that I've met over the last couple of years, are really worrying, most of them look like they've just left school and they're designing big Concrete buildings!.