Maura

I've not only stood on the glass floor in the Toronto Tower, but jumped up and down on it with all my might.

Did that to see:

1) whether there was any deflection - there wasn't

2) how other people present would react - with some amazement needless to say

I had previously looked at it and believed that I could say at least a triple laminate double-glazed unit (and possibly more).  I also felt that the triple laminate was probably at least 1" thick.  And given the relatively small size of the panes of glass, (2' by 2' I think), it didn't surprise me when I couldn't get any deflection to occur.

Just because glass bends doesn't mean it will break.  Two anecdotes.

a)  We tested a piece of 6mm thick (1/4") tempered glass held at the four corners with sliding brackets (free to move).  Lateral loading using air pressure. The panel was about 6' high.  It deflected nearly 200mm (8") before it broke!

b)  On a high rise building in Melbourne, new occupants complained about the way the windows wobbled when the wind blew.  The developer of the building, a big bear of a man, decided to demonstrate how safe the windows were by running at the glass full pelt.  He bounced!  A colleague of mine, the designer of the curtain wall, was present.

Of course, this comes back to perceptions of reality.  People see glass moving and think it is easily broken.  People see broken glass and this is confirmed in their minds.

Regards

david