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Mass timber is a sustainable option for building design compared to traditional steel and concrete building systems. A shake table test of a full-scale 10-story mass timber building with post-tensioned mass timber rocking walls will be conducted as part of the NHERI TallWood project. The rocking wall system is inherently flexible and is expected to sustain large interstory drifts. Thus, the building’s vertically oriented non-structural components, which include cold-formed steel (CFS) framed exterior skin subassemblies that use platform, bypass, and spandrel framing, a stick-built glass curtain wall subassembly with mechanically captured glazing, and CFS framed interior walls, will be built with a variety of innovative details to accommodate the large drift demands. This paper will describe these innovative details and the mechanisms by which they mitigate damage, provide an overview of the shake table test protocol, and present performance predictions for the non-structural walls. 

During extreme events such as earthquakes, stairs are the primary means of egress in and out of buildings. Therefore, understanding the seismic response of this non-structural system is essential. Past earthquake events have shown that stairs with a flight to landing fixed connection are prone to damage due to the large interstory drift demand they are subjected to. To address this, resilient stair systems with drift-compatible connections have been proposed. These stair systems include stairs with fixed-free connections, sliding-slotted connections, and related drift-compatible detailing. Despite the availability of such details in design practice, they have yet to be implemented into full-scale, multi-floor building test programs. To conduct a system-level experimental study using true-to-field boundary conditions of these stair systems, several stair configurations are planned for integration within the NHERI TallWood 10-story mass timber building test program. The building is currently under construction at the UC San Diego 6-DOF Large High-Performance Outdoor Shake Table (LHPOST6). To facilitate pre-test investigation of the installed stair systems a comprehensive finite element model of stairs with various boundary conditions has been proposed and validated via comparison with experimental data available on like-detailed single-story specimens tested at the University of Nevada, Reno (UNR). The proposed modelling approach was used to develop the finite element model of a single-story, scissor-type, stair system with drift-compatible connections to be implemented in the NHERI TallWood building. This paper provides an overview, and pre-test numerical evaluation of the planned stair testing program within the mass timber shake table testing effort. 

Two partition walls with return walls at both ends and traditional slip-track detailing were investigated. Special gap details were evaluated to reduce damage at the wall intersection. The first detail utilized a large gap in the wall intersection, while the other detail utilized distributed gaps along the wall. The walls were tested under a bidirectional loading protocol, to provide better insight into the wall intersection behavior under bidirectional loading. 

The slip behavior of two straight drywall partition walls (without return walls) – one with conventional slip-track detailing and the other with telescoping detailing – was examined. These drywall partition walls were tested under a bidirectional loading protocol, which allowed for systematic evaluation of the effect of out of plane drift on the in-plane resistance of the drywall partition walls.