An experimental investigation of multi-panel cross-laminated timber shearwalls

This paper presents an experimental investigation on single-storey multi-panel Cross-Laminated Timber (CLT) shearwalls subjected to lateral loads. The study focuses on shearwalls with a variable number of panels and considers factors such as dead load and the relative stiffness between the panel-to-panel connections and hold-downs to achieve two distinct kinematic modes, namely Coupled-Panel (CP) and Single-Wall (SW). Twelve full-scale tests were conducted, covering two primary configurations: one in which sliding was prevented through supports, and another where sliding was resisted by angle brackets. The findings revealed that gravity load enhances shearwall resistance in both CP and SW, while having limited impact on stiffness and ductility. Walls exhibiting SW had greater stiffness but lower ultimate displacement and ductility due to the increased number of panel-to-panel connections. Increasing the panels quantity while maintaining the same shearwall length reduced resistance and stiffness, while ductility improved slightly. It was also observed that adding angle brackets resulted in enhanced resistance. Reasonable agreement was found when the experimental results were compared with the numerical model, including close alignment between observed kinematic modes and those predicted through numerical analysis. The numerical models also appropriately predicted the plastic regions, capturing yielding and local failure in the connections. Comparison between test results and analytical expressions, recently adopted in the Canadian timber design standard and forthcoming Eurocode 8, showed that the analytical expressions can adequately capture the kinematic modes and yield hierarchy with acceptable accuracy, particularly in predicting the wall’s lateral strength.