Slate Strength

Hello-

I am trying to find information about the strength of slate flooring with particular interest in how much deflection a floor can have before the slate cracks and (http://maplered.com) breaks. In addition, I am looking for infomation about a particular product, Brazilian "Rusty Slate" (basically dark grey with iron deposits that give it rust colored patches).

The information I am looking for is, for instance, with a 2'x2'x1/2" slate set in a mortar bed, how much can the floor deflect before the slate will break? With a 2,000 lb point load on the slate? How much deflection can the slate take if the thickness is reduced to 3/8" thickness? How much deflection can the slate take if it is 1'4"x1'4"x3/8"?

Is there any source for information such as this? Can you help me?

Thanks for any assistance you can give!

Brian D. Rich, AIA, NCARB
Architect
LMN ARCHITECTS
Suite 501, Norton Building
801 Second Avenue
Seattle, WA 98104
ph.: 206.682.3460 x307
fx.: 206.343.9388
brich@lmnarchitects.com