CLT Shear Walls Aspect Ratio

[EngTipper.]

CSA O86:19 recommends aspect ratios for CLT shear walls to be between 2 and 4 to promote rocking instead of sliding.

If I have a 4m storey height, the wall lengths must be between 1m and 2m long to meet the aspect ratio requirements.

Now say the panel sizes are all 2m wide (still 4m tall). Am i allowed to make a 6m long shear wall segment if all of the panel to panel joints are connected with energy dissipated connections? The hold downs would still only be at the corners of the segment, so 6m apart. In this case the aspect ratio of the entire wall segment would be less than 2 but i think this is the intent of clause 11.9.3.5.3 and 11.9.3.3.1.

 

[Luceid]

I haven't designed this exact type of system myself - however the testing and lecture material I have seen have all had rows of panels with interlocking steel connectors so the panels rock individually but still connect to one another. CLT shear walls are still making their way into the US code though - so I don't have a definite answer for you.

 

[jayrod12]

In the little bit I learned about this, it's tough to create a flexible enough connection between the panels. Essentially I've been told if you look at it as segmented, but it acts as a full wall, your anchorage forces may be unconservative. So the recommendation I was given was to design it as a single wall segment and connect the panels to each other rigidly enough to enforce this behaviour.