Sizing CLT walls at concept design

[m_struct]

Looking for a rule of thumb or quick design checks for laying out and sizing CLT bracing walls at concept design. Maybe something like - "limit V* to ____ per linear __"

 

[Agent666]

Have a look at how many nails you can practically fit (or are willing to put) between panels on vertical panel joints, as you want the vertical joints to be the ductile mechanism. The vertical shear flow is the same shear flow on horizontal joints to floors. Therefore, this is the max load you might hope to develop.

Currently looking at a job where we have proposed a max of ~5mm nails at 50 ctrs, this equates to a design capacity of ~35kN/m, You'll basically be limited to quite low ductility's if you code has a max nail slip value (we have 6mm max limit). Least that's my experience. Lots of research/testing to higher load values that cannot be obtained if you adapt current code requirements.

This 35kN/m value is basically the same you get from a decent ply shear wall system (like Simpson ATS), which I'd prefer to be designing. Once you factor in overstrength, if you have a CLT diaphragm, then if you maxed out the wall panel nails you'll need even more fixing capacity in the diaphragms for resisting overstrength loads (so be aware of this if maxing out CLT wall capacities.

I personally don't really see the point in CLT walls unless you have a very regular layout, lots of walls and relatively low lateral loads.

https://engineervsheep.com