Need E - value for 2x8 SYP M23 2

[AELLC]

Please, I need this urgently for a meeting with a prefab wood truss mfr.

I need to calculate a girder truss deflection by hand today to verify the truss software output.

 

[AELLC]

If not able to find M23, please inform me E for 2x SYP #1 (according to IBC 2006) - not the new values in IBC 2012

 

[EngineeringEric]

Per 2001 NDS. SYP #1: 2"-4" wide E = 1,700,000 psi :: Fb = 1500psi :: Ft=825psi
-FYI
Per 2001 NDS. SYP SS: 2"-4" wide E = 1,800,000 psi
Per 2001 NDS. SYP #2: 2"-4" wide E = 1,600,000 psi

And you obviously know that these values were dramatically decreased recently (by some 30%!!)

 

[AELLC]

Eric

Thanks a million. I heard they changed but I didn't know exactly what because I don't have the latest NDS.

This will give more ammo in my conflict with the truss designer, regards my other post.

 

[EngineeringEric]

Now the 30% is not a true number, only some values changed and they changed by different amounts (fb, Fc, Ft, etc...). I am sure they will have a hard time arguing against you!

 

[RWW0002]

See attached from southernpine.com (free publication)

 

[AELLC]

Well, the girder truss deflection they came up with is too close for comfort (for me), but I just re-calced it again and it looks like the deflection is barely within Code.

I have lot of other very serious doubts, however...I just needed to make a list of reasons why I am rejecting their repair, and I had serious doubts as to the accuracy of their truss software.

 

[EngineeringEric]

The truss software is in question? That is a major issue. I would mention to you that most the proprietary truss packages assume a slight spring connection at the plates which makes their models nearly impossible to replicate by hand or in RISA/Other.

 

[AELLC]

Eric, then this truss software may not have included that spring connection. One more critique to add to my list. Thanks.

 

[AELLC]

RWW, thanks.

It shows the values for M-23.