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A test program was designed to answer if it is possible to design and build a tall mass timber building with resilient performance against large earthquakes. Resilient performance was defined as to receive no structural damage under design level earthquake, and only easily repairable damage under maximum considered earthquake. The system under investigation is a full-scale 10-story mass timber building designed and constructed with many innovative systems and details including post-tensioned wood rocking wall lateral systems. Non-structural components on the building were also tested to ensure their damage in all earthquakes are repairable and will not significantly delay the functional recovery of the building after large earthquakes. The tests were conducted using multi-directional ground motion excitations ranging from frequent earthquakes to maximum considered earthquakes. The resultant dataset contains a total of 88 shake table tests and 48 white noise tests conducted on the building at the high-performance outdoor shake table facility in San Diego CA. U.S.A. Data was obtained using over 700 channels of wired sensors installed on the building during the seismic tests, presented in the form of time history of the measured responses. The tall wood building survived all excitations without detectible structural damage. This publication includes detailed documentation on the design and testing of the building, including construction drawing sets. Representative photo and video footage of the test structure during construction and testing are also included. This dataset is useful for researchers and engineers working on mass timber building design and construction in regions of high seismicity. 

Nonlinear time history analyses were conducted for 5-story and 12-story prototype buildings that used post-tensioned cross-laminated timber rocking walls coupled with U-shaped flexural plates (UFPs) as the lateral force resisting system. The building models were subjected to 22 far-field and 28 near-fault ground motions, with and without directivity effects, scaled to the design earthquake and maximum considered earthquake for Seattle, with ASCE Site Class D. The buildings were designed to performance objectives that limited structural damage to crushing at the wall toes and nonlinear deformation in the UFPs, while ensuring code-based interstory drift requirements were satisfied and the post-tensioned rods remained linear. The walls of the 12-story building had a second rocking joint at midheight to reduce flexural demands in the lower stories and interstory drift in the upper stories. The interstory drift, in-plane wall shear and overturning moment, UFP deformation, and extent of wall toe crushing is summarized for each building. Near-fault ground motions with directivity effects resulted in the largest demands for the 5-story building, while the midheight rocking joint diminished the influence of ground motion directivity effects in the 12-story building. Results for both buildings confirmed that UFPs located higher from the base of the walls dissipated more energy compared to UFPs closer to the base. 

Wood buildings in North American has been predominantly constructed using light-framed wood systems since early 1900’s, with only limited exception of heavy timber construction in some non-residential applications. This situation is likely to change in the future with the growing acceptance of mass timber construction in the region. In fact, a number of mass timber buildings have been constructed in recent years in the U.S. and Canada, including low- to mid-rise mixed-use buildings (e.g. UMass Student Center, T3 building) and tall towers (e.g. Brocks Commons at UBC). Most of these buildings utilized cross laminated timber (CLT) or nail laminated timber (NLT) floors and heavy timber framing systems to support gravity loads, and a non-wood lateral system such as concrete shear walls or a braced steel frame to resist wind and seismic loads. Although CLT material and glulam products have been recognized in the U.S. and Canada (IBC (2018) and NBCC (2015), there is currently no mass timber lateral systems in the U.S. and only one system (platform style panelized CLT shear wall) in Canada that is currently recognized by the building codes. As a result, special design procedures and review/approval processes must be followed for any building intended to use a mass timber lateral system. There is a need to promote codification of mass timber lateral systems in order to help further develop mass timber building market in North American. At the time of this paper, there has been an on-going effort to devel-op seismic design parameters for panelized CLT shear walls in the U.S. (ref) following the FEMA P695 procedure for platform construction. The other lateral system that at-tracted significant attention and research resources is post-tensioned CLT rocking wall system, which has the potential to be applicable to balloon framed low-rise to tall wood buildings. This paper will focus on recent research development on CLT rocking wall system in the U.S. and the effort to develop a seismic design procedure for this system for inclusion in the NDS Special Design Provisions for Wind and Seismic (SPDWS)(2008). While the expensive and time consuming process of the FEMA P695 process would provide the ability to use the equivalent lateral force method for design purposes, this path is not part of the discussion included here.