There's something wrong in the physics of engineering, as I have always said. This is a common state, since we always learn something new with every big collapse. Might as well say the Sun will rise.
However, this collapse really exposes the mismatch between perception and reality. All the pre-damage they were talking about is classic surface rebar corrosion of the Gardiner Expressway type. Nothing that would lead to the collapse. There has to be some more physics here.
All buildings have a built-in seismic capacity, which is defined as what it will take to damage the building in terms of peak ground velocity - PGV. As the sc approaches zero, you will get static collapse. So, we know that old Florida buildings have a very low seismic capacity. Apparently, they claim that Hurricane Andrew raised the building standards. Perhaps they are up to 10 cm/s, since wind loads and seismic loads are similar. I tend to doubt it, but there are only sinkholes in Florida, and no earthquakes.
Buildings should not collapse with an earthquake, hurricane or sink hole. People should be able to get out. We saw this with the big Chile earthquake, the buildings tilted, and in one case tipped over, but they were intact. You only had to worry about your Grand Piano rolling over you.
Unfortunately, Chile exposed the dangers of the latest trend in condos - soft storeys and transfer slabs. For Toronto, a rock foundation solves many problems, but these Burlington towers are right on the Hamilton fault. I've written the scenario for this fault. It let go with an M7 a few thousand years ago, and has the usual 1 in 10,000 per year of going again. The history is written in the topography, and the disturbed sediments in Lake Ontario. Nobody cares.
These towers are to be built on the hanging wall of the fault. The pgv is expected to be a record-breaker of 1 m/s, and nothing can withstand that. But, in world without physics, we go on living memory, and stories from our grandparents. No earthquakes there.
Anyway, with the Great Toronto Real Estate Collapse upon us, I doubt the towers will be built. No need for more 'coin laundry' empty suites. :)
ps. all buildings that have collapsed passed inspection. Even the most horrible exposed rebars are fixed by plastering on a new coat of concrete. Is there something wrong here? The most famous is the Churchill NZ collapse, totally passed inspection, and a pile of rubble the next day. These buildings die of fatigue from previous loads, be it storms, parties, or earthquakes. Totally invisible damage. Expect to see more of this.
pps. lots of identical buildings about. Will they accept the phoney assurances of inspection?
I think that nobody cares for these people. The first building inspector is using the 'Stupidity Defence' of not remembering anything. No inspectors or engineers will undermine this defence in the US, since they sue anybody and their dog. And the new buildings will use the 'That was then, and this is now.' defence.
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