3d modeling for wood shearwall diaphragm design

[lanejoe10]

What programs have people been using to model semi-rigid wood diaphragms and wood shearwalls?

Has anyone ever used RAM Elements? If so, what are the goods/bads and things to be aware of?

thanks

 

[JoshPlumSE]

Haven't use RAM Elements for that sort of thing before. I've done it in RISA, however. RISA has a number of options related to wood shear walls to get the analsyis / design correct. This is tricky with walls as there is interaction between wall flexural deforamation, wall shear deformation, nail slip, hold down deformation, et cetara. Very difficult to get this right in the analysis.

Diaphragms aren't quite so bad as you're mostly only dealing with elastic properties (flexural and shear deformation) and nail slip. And, the new NDS formulas for calculating a Ga (apparent shear modulus considering nail sli) really make this easier.

One word of caution: Wood diaprhagms are so flexible that you will probably need to sub-mesh the diaphragm further than you would for any other type of diaphragm. If your meshing is too coarse, then you're like to get some artificial rigidity out of that diaprhagm.