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A lateral force resisting system (LFRS) comprised of one eight-foot-wide Mass Ply Panel (MPP) with Buckling-Restrained Braces (BRBs) was attached to the building frame and tested following a cyclic quasi-static loading protocol up to 4% roof drift ratio. This system was designed to pivot about a pinned base, allowing the wall to rotate with minimal flexural restraint, thereby distributing drift demands more uniformly across the building height and reducing crushing damage at the wall base. Under first-mode loading, the system exhibited stable hysteretic behavior with a nearly uniform story drift profile, while second-mode loading revealed near-linear behavior with high stiffness. Experimental results provide valuable insights into the behavior of mass timber seismic lateral force-resisting systems and can be reused to develop and validate design guidelines for their broader implementation in seismic regions. 

Mass timber panels are emerging as an innovative alternative for the design of elastic spines due to their high stiffness- and strength-to-weight ratio, among other factors. Recent research has shown that mass timber panels used in conjunction with steel energy dissipators are promising solutions for enhanced seismic performance. However, the available experimental data at the building scale is still minimal, which limits the understanding, adoption, and development of effective seismic design guidelines for these systems. This research addresses this gap through full-scale quasi-static cyclic testing of a three-story mass timber building. Lateral loads are transferred through Mass Ply Panel (MPP) diaphragms to an MPP spine with vertically-oriented unbonded steel buckling-restrained braces (BRBs) as energy dissipating boundary elements in the first story. The only elements designed to dissipate energy in the inelastic range are the BRBs. The building specimen achieved low-structural damage and enhanced-performance goals, being able to reach a 4% roof drift ratio with little loss of strength and stiffness. The proposed pivoting detail was effective in mitigating compressive damage at the wall toe. To support the experimental campaign and future design procedures, a high-fidelity numerical model of the building was developed using OpenSees. 

This paper describes the lateral force resisting system (LFRS) design in a full-scale six-story shake-table test building and presents a comparative cradle-to-grave life-cycle assessment of alternative LFRSs. The test building features the reuse of material from a ten-story shake-table structure comprised of engineered mass timber (MT) products. These include MT floors (cross-, glue-, nail-, and dowel-laminated timber [CLT], [GLT], [NLT], [DLT]); MT posttensioned rocking walls (CLT and mass ply panels [MPP]); and a gravity system consisting of laminated-veneer lumber (LVL) beams and columns. Shake-table testing will benchmark innovative, low-damage design solutions for the LFRSs. To supplement this test, the environmental impact of a MT LFRS is determined relative to design alternatives that use conventional materials. The Athena Impact Estimator for Buildings was used to perform a comparative, cradle-to-grave life-cycle assessment (LCA) of the prototype MT LFRS with respect to an alternative, functionally equivalent reinforced concrete (RC) shear wall design. The LCA results showed reduced environmental impacts across some impact metrics, with a significant reduction in Global Warming Potential for the MT LFRS when accounting for biogenic carbon.