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TROPICAL HARDWOODS

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I am looking for the shear strength of "ipe", a Brazilian tropical hardwood 
for use in a boardwalk.  Yes, it is spelled IPE.  Other common names for it 
include Amapa (Mexico) & Lapacho negro (Argentina).

Some good news and bad news.  The bad news is the boardwalk needs to allow 
for a 70,000 pound fire truck to cross (16,000 pound wheel load).   The good 
news is the boardwalk planks bear on sleepers which bear on a grout bed 
which bear on a structured concrete floor, so if a plank fails, the truck 
won't fall too far!

I have found the following values for ipe (ultimate values I think).

     Bending strength 22,000 to 28,000 psi  (depending on moisture content)

     Modulus of elasticity  2,920,000 to 3,350,000 psi

     Maximum crushing strength  10,350 to 14,000 psi

Any thoughts on factors of safety to apply to the above values for use in 
allowable stress design?  Or if LRFD (yikes!), any thoughts on capacity 
reduction factors (phi) combined with load factors?

Also I could not find a shear strength.  (Something equivalent to 95 psi for 
Douglas Fir Larch).  Has anyone worked with ipe before?   I thought about 
proportioning the shear strength up based on the ratio of modulus of 
elasticity to get a ballpark estimate.

Steve Uthoff, S.E.