The growing demand for sustainable urban development has accelerated the adoption
of mass timber systems, with cross-laminated timber (CLT) emerging as a promising solution
due to its structural efficiency. While platform-type CLT shear walls are currently included in
design standards such as the NBCC and CSA-O86, balloon-type configurations provide
various advantages such as reduced cumulative shrinkage and fewer floor-level connections.
In this thesis, the seismic performance of two-storey balloon-type coupled-panel CLT
shear walls was evaluated through full-scale experimental testing. Different connection
configurations: i) screw orientation in hold-downs (HD); ii) stiffness of vertical joints (VJ);
and iii) addition of tension straps (TS) and horizontal splices were evaluated to study their
impact on lateral load resistance, stiffness, cyclic strength degradation, and energy dissipation.
Across all tests, walls with mixed-angle HD demonstrated higher initial strength than
shear-only configurations at lower drift levels but experienced more strength degradation at
larger drifts. Increasing VJ stiffness enhanced performance. At the maximum drift of 5.7%, all
balloon-type CLT wall configurations maintained global stability despite significant inelastic
deformation and localized connection damage.
Compared to platform-type systems, balloon-framed walls achieved improved lateral
resistance and more uniform inter-storey drift distribution. The findings provide valuable
insight into the seismic behavior of balloon-type CLT shear walls and emphasize the critical
role of connection detailing in achieving resilient structural performance.
