Cross laminated timber (CLT) shear walls are an efficient lateral load resisting system for mass timber buildings. Ductility and energy dissipation of timber buildings is mostly provided by well detailed connections. Therefore, to achieve good seismic performance of CLT shear walls, hold-down connections must be not only strong and stiff but also ductile with sufficient displacement capacity to meet the drift demands. A novel hold-down connection is proposed using a mixture of screws installed at an inclined angle and 90° to the grain. The respective benefits of inclined and 90° screws can be combined to create a strong, stiff, and ductile connection. Two stages of experimental testing were undertaken with target connection capacities of 600 kN and 1200 kN respectively. The experimental results confirmed that mixed angle screws can provide a strong, stiff, and ductile hold-down solution for CLT shear walls. The optimal ratio of 12mm inclined screws to 10mm 90°screws was 1:2, and the optimal ratio of 12 mm inclined screws to 12 mm 90°screws was 1:1.5. The primary failure modes were screw withdrawal and wood embedment crushing. Only localised damage of timber around the screw holes was observed and this was repaired with epoxy. New screws were then reinstated with a small offset to the original screw locations and the repaired hold-down connections were found to have the same or even slightly better performance.
