Withdrawal at an Angle in Wood

[otto_eng]

I am designing a connection for a hanger wire. The connection is that an eyebolt will be anchored to a 2x4 joist with 45 angle. The pullout on cable is 150lbs. I was wondering if I can use Equation 11.4-1 (NDS 2005) for this connection type. I am wondering how I can be sure that fibers of the wood will be fine . I would be happy if I can get an input.

Thank you,

 

[racookpe1978]

And we would be happy if you would provide a sketch or dwg. 8<)
Seriously, please add a sketch, with the angle of the tension force and and angle of the eyebolt included. I think the two are the same (at the 45 angle ?) but any potential difference is essential.
Also, what kind of wood, what direction of wood grain, and what location and Code are you building to?

 

[otto_eng]

Please see attached.I think it explains everything. Douglas fir, IBC .

 

[Guastavino]

The way I read 11.4-1 (my NDS 2005), I read that it is for when the load is applied at an angle BUT the screw is installed perpendicular to grain.

I'm not sure about some research on something like that. Can you make the eyebolt perpendicular to grain?

 

[dhengr]

Loti_eng:
Your problem is strictly a withdrawal/pull-out problem, and it is generally taking place perpendicular to the grain. Although, you could parse the withdrawal/inch of penetration a bit if you considered a screw thread which penetrated radially/perpendicular/across to the growth rings vs. one which tended to penetrate tangentially/along the growth rings. The NDS does this by setting its allowable withdrawal values at the lower ult. cap’y. of the various possibilities. NDS section 11.4, “Combined Lateral and Withdrawal Loads” does not apply to your sketch. But, your problem does induce bending moments/loads about both the x & y axes, and this should be studied, and added to the existing stresses in the 2x4..

 

[otto_eng]

dhengr:

Thank you for your response. If I anchor the screw from the bottom face of 2x4. I think I can use the equation but since it will be connected from the bottom of 2x4 not side of it, how should I find the z value of the screw ? since the tabulated values are for wood to wood connections..