Seismic performance of a scaled three-story braced timber frame building with elastomeric damper through shake-table tests

This study investigates the seismic performance of a half-scale, three-story mass timber frame with and without a chevron bracing and elastomeric damper (CB-ED) system through shake-table testing. The objective was to evaluate the CB-ED system's effectiveness as an innovative seismic force-resisting system capable of reducing seismic demands while maintaining interstory drifts within the 2.5% limit prescribed by the National Building Code of Canada (NBC). The specimen was subjected to a suite of scaled ground motions at varying intensity levels to assess its dynamic characteristics, and seismic response. Results showed that the inclusion of the CB-ED system reduced the fundamental frequency by approximately 17% and increased the effective damping ratio by 18%. Reductions of up to 40% in brace forces, 18% in floor accelerations, and 24% in base overturning moments demonstrate the system's capacity to alleviate force demands on both structural and non-structural components. Conversely, the addition of dampers lengthened the structural period, leading to larger displacements and, in some cases, slightly higher interstory drifts; however, all drift ratios remained within NBC limits, with notable reductions in upper-story drift that typically govern non-structural damage. These experimental findings highlight that integrated damping and bracing systems such as the CB-ED concept hold strong potential for achieving robust seismic performance when appropriately tailored to the structural and architectural context. • Shake-table tests on timber frame with chevron bracing–elastomer damper (CB-ED). • CB-ED increased damping by 18% and reduced frequency by 17%. • Brace forces and floor accelerations dropped by up to 40% and 18%, respectively. • All interstory drifts stayed within the 2.5% National Building Code of Canada limit. • CB-ED offers strong potential for low-damage seismic design.