Construction and seismic testing of a resilient two-story mass timber structure with cross laminated rocking walls

Abstract

With the rising popularity of mass timber building in the United States, there is a need to develop efficient wood-based lateral systems to enable design of mass timber buildings in regions with high seismicity. This thesis summarizes the construction and testing details of a full scale shake table testing program for a two-story mass-timber structure with a resilient post-tensioned rocking wall lateral system made from cross laminated timber (CLT) product. The post-tensioned rocking walls helped to dissipate seismic forces while allowing the other parts of the structure to remain damage-free through multiple seismic events. The utilization of a balloon framing style rocking wall system and heavy timber gravity frame enabled an open floor plan (compared to compartmentalized CLT construction) that has better potential for modern commercial and office use, which can help improve market competitiveness of mass timber construction. Since the work conducted in this thesis is only part of a large multi-university collaborative research project aiming at designing tall wood buildings for high seismic regions, only the construction, testing process, and resulted data related to building resiliency are discussed. The details and data that are in part presented in this thesis are to serve as a benchmark dataset for dynamic performance of this new building type that can be referenced by the wood design community. The first part of the thesis discusses design considerations, construction methods, and instrumentation setup employed in the test program. Practical issues encountered during construction and testing were also discussed together with suggestions for improvement in the future. The second part of the thesis presents the data collected from the shake table tests, with comparison to initial design assumptions. The final section of the thesis contains some conclusions that can be drawn from direct observations of the test results.