Seismic Design and Performance Evaluation of Post-tensioned CLT Shear Walls Coupled with U-shaped Flexural Plates

Post-tensioned cross-laminated timber (PT-CLT) walls coupled with U-shaped Flexural Plates (UFPs) have proved to be a low-damage seismic force-resisting system (SFRS) due to their self-centring capability and enhanced energy dissipation. However, a comprehensive study is yet to examine their seismic performance in regions with high seismicity and complex seismotectonics. This paper assessed the seismic performance of PT-CLT shear wall buildings with UFPs. Three-, six-, and nine-storey prototype buildings were designed based on the direct displacement-based design (DDBD) method and seismic hazard in Vancouver, Canada. The assessment considered the most recent seismic hazard model provided in the 2020 National Building Code of Canada (NBCC). Two-dimensional fibre-based numerical models were developed and validated at the component-, system-, and building-levels. Nonlinear response history analyses were carried out to assess the structural responses and validate the DDBD procedure. Incremental dynamic analyses were conducted to examine the buildings’ collapse capacity, using 80 ground motions that were selected for each building and scaled to each seismotectonic regime’s Conditional Spectrum. The IDA results demonstrate that all the studied buildings have adequate collapse margin ratios, with less than a 10% chance of collapse at maximum considered earthquake events.