Friday, June 21, 2013

Toronto seismic issue in waiting

Well, I'm not getting sued for saying anything like this is worst ever.  I'm sure they are absolutely perfect, but look at this crap:

This is the first floor of the old Women's College building being demolished.  A huge mass on dinky columns.  All brick.  Not a chance for seismic.  But not a hazard since it is being demolished.  In fact, all the crappy brick buildings are being torn down, which is good for seismic, but history-buffs will whine.  I just put this in for perspective.

Now, this new monstrous condo is going up.   Look, it has all shops on the bottom with larger dinky columns, but 10 times the mass.

Look up, look way up!

They're all built this way, perfect 2 Hz resonators on a soft-story base.  The huge tower sits on a massive slab spanning the house of cards.  Buildings like this did terrible in Chile, but they still go up.  The only good thing is that they are on rock, but I don't know if the floppy build negates this advantage.

Unfortunately, this passes all the conventional seismic analysis, based on peak acceleration and shake tables.  We must wait for the proper earthquake to provide lessons.  :)

If you own this, get total earthquake 'unavailability' insurance if you can.  That way you can rent another place when this gets closed by an earthquake.


Anonymous said...

That's why my condo has a constant shear wall profile down to bedrock. No transfer slabs for me. It is very slender though, so I hope we don't tip over or get smashed by an adjacent building! I often wondered if wind force governs design over seismic.

Harold Asmis said...

That's the best, and in that case wind is over seismic.