How to Model Nail Behavior in Wood?

[metalman8357]

Hi Everyone,

I'm working on analyzing steel sheets that are fastened to wood with nails and loaded in shear. I'm having a difficult time figuring out how to model this behavior. The nail is loaded in shear and pulls out of the wood, deforms, and deforms the wood. Can anyone give me advice on how to model this accurately? The only thing I know is the amount of pullout force that is required to remove a nail in straight withdrawal.

 

[inline6]

why not use a beam element and look at axial force and shear etc?

 

[frusso110]

Isn't the bigger issue how to model the material properties of wood? What is the question you are trying to answer?

 

[focuseng]

Have you consulted the Forest Products Laboratory library yet? You need to get a copy of the research done on the origin of the yield mode equations as published in the NDS. There are several papers you will want to get a hold of and most are referenced directly in the NDS.

Some references you need to get a hold of my collections:
FPL-RP-505
FPL-GTR-54
FPL-RP-470*** <- get this one
FPL-RP-469*** <-get this one
"Theoretical Design of a nailed or bolted joint under lateral load", 1955, USDA, Forest Service, Forest Products Laboratory #D1951
"Evaluation of Nail Dowel Bearing Strength Expression", Rammer, Proceeding of the 1999 structures congress, 1999
AF&PA technical report 12


Must do your homework on this one. A lot of the yield theory and empirical is explained. Start with a thorough search of the FPL library and probably call them to get some help.

______________
MAP

 

[MechEng2005]

Make sure that whatever analysis you are doing is non-isotropic, to begin with.

 

[bkal]

I agree with frusso, especially his second question:

What is the question you are trying to answer?