Does anyone have a set of design values for Black Cherry used as a joist? I need the following values if available.
E (Modulus of Elasticity)
Fv (Max Horizontal Shear)
Fb (Max fiber stress in bending)

Thanks much.

hi, I received this info from Joe Miller in a question about white ash....

"Chapter 4 of the Wood Handbook (there is a link to it on the main Guild page) has all sorts of UNADJUSTED strength properties for ash and other species."

there was also a link which doesn't work anymore...
http://www.fpl.fs.fed.us/documnts/FPLGTR/fplgtr113/fplgtr113.htm

however, I printed the info for my white ash and black cherry is on the same page. Here are the values:
E = 9000MPa green/10300@12% moisture
Fv (parallel shear?) = 7800kPa green /11700@ 12%
if fiber stress in bending is the same as "modulus of rupture", then the value is 55000kPa green and 85000 @12%

if this info is undeciferable gobldeegoop, perhaps you can find the wood handbook. or ask me and I'll try to clarify.

Joe had said it was on the tf main site, but I could not find it tonight.

Hey guys and I thought my vision was going:
right smack dab in the middle of the guild home page the Wood Handbook is available for download at nada cost. Kinda big, may go faster a chapter at a time.
have fun

They work for me. Thanks much.

I had a complete copy of the wood handbook burned to a CD so it would always be handy. Of course I've no idea where the CD got to.

The values for "E" are a numerical average, which is reported in the Wood Handbook for small, clear, straight grained specimens. (Translation = select structural)

Fb and Fv are based on a 95% inclusion (the design values will be OK for 95% of the timbers), and then are decreased by an additional factor of 2.3 (See ASTM D245 if you are really, really bored.) In essence, a reduction of about 4-6 from the posted average values.

So an interpretation/adjustment from the woodhandbook could yield:

E = 1.3x10E6 psi for Select Structural
Fv = 210 psi for all grades
Fb = 1,300 psi for Select Structural

And the disclaimer: This is just one interpretation of the results, and is by no means should be construed as a usable design value until fully investigated according to the appropriate grading rules . . .

Thanks for the adjustment for Fv & Fb, that saved me a bit of reading.
One question; My understanding was that we should always use the values for no.2 when engineering a frame but in another post I've seen select structural numbers being used for Doug Fir.
Am I mistaken in this?
Is some 'authority' out there certifying Doug Fir timbers (5"+) as select structural?
Do you know a simple rule of thumb to further adjust the select structural values for Fb & E down to no.2?

It comes down to whether you know what you are getting. I use select structural with some clients since I know that is what will be used, and with others I use something less. We also specify what to use on the drawings so that we get what we are using in design.

Hope that helps

Typically, if you have an ungraded timber (which is standard in the timber framing world; it comes from a local mill or sawyer), you should use the lowest assumed grade or run the risk of a building official rejecting a timber.

With Doug Fir in particular, it is fairly easy to get graded timbers (typically, DF comes from larger mills out west, where graders are prevalent), so specifying a higher grade in such species is not uncommon. (I've even specified Dense SS DF once...)

You can get a copy of the NELMA (whatever the grading agency is for that particular species) manual and use their grading rules to ascertain whether a timber is of a higher grade than #2 (they have all sorts of pictures in the ones I've seen). When you do this, you run the risk of someone rejecting your grading (since you are not a certified grader), which means you have to go back to the lowest grade in that category.

Typically, a #2 timber isn't overly attractive; it would get rejected for visual reasons before it would get rejected for structural reasons.

Looking through the NDS supplement for other design values, it appears a #2 grade for other species is around 54% of the SS value for FB, and 80% for E. It would be reasonable to make similiar reductions to cherry.