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Driven by demand for sustainable buildings and reduction in construction time, mass timber, specifically cross-laminated timber (CLT), is being more widely used in mid-rise buildings in the US. In areas of the US with a significant seismic (i.e. earthquake) hazard, mass timber buildings that are seismically resilient are of significant interest. Low damage post-tensioned self-centering CLT shear walls (SC-CLT walls) provide an opportunity to develop seismically resilient CLT buildings. There is however insufficient knowledge of the lateral-load response and damage states of SC-CLT walls under multidirectional seismic loading conditions, which can have a pronounce effect on the seismic resilience of buildings with SC-CLT walls. In order to fill this knowledge gap, a series of lateral-load tests were performed at the NHERI Lehigh Large-Scale Multi-directional Hybrid Simulation Experimental Facility to investigate the multidirectional cyclic behavior of a low damage, resilient three-dimensional CLT building sub-assembly with SC-CLT coupled shear walls, CLT floor diaphragm, collector beams, and gravity load system. Comparisons are made between the lateral-load experimental response of the SC-CLT walls under unidirectional and multidirectional cyclic loading.
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This content will become publicly available on January 1, 2026
Full-scale shake table test of resilient six-story hybrid mass timber and steel structure
Mass timber solutions are becoming more and more viable for high-seismic regions while remaining sustainable, efficient, and affordable. The industry is driving innovation leading to the development of resilient hybrid steel-mass timber solutions that can minimize post-earthquake losses and downtime. A resilient six-story hybrid mass timber structure with: [i] laminated veneer lumber (LVL) beams and columns, [ii] a cross-laminated timber (CLT) selfcentering rocking wall (SCRW) in one direction, and [iii] a steel moment frame/concentric braced frame (MF/CBF) in the other direction was tested at the University of California, San Diego (UCSD) large high-performance outdoor shaketable facility. The dynamic testing included uni-, bi-, and tri-directional ground motion time histories applied at increasing intensities, including 43- and 225-year hazard levels, design earthquake (DE) level, and risk-targeted maximum considered earthquake (MCER) level per ASCE 7-16 for a location in Seattle, Washington. Four (4) design earthquakes and two (2) risk-targeted maximum considered tri-directional earthquakes were applied to the structure. Testing resulted in peak story drift ratios of 2.4% and 1.4% in the SCRW and MF/CBF directions, respectively. Even at MCER levels of shaking, the performance-based seismic design allowed for (1) the CLT-SCRW to remain essentially undamaged and (2) the MF to remain essentially elastic, providing elastic restoring forces, while the CBF provided stable and controlled hysteretic energy dissipation. After testing, residual drifts were smaller than 1.6 mm (1/16 inch) at the roof, indicating that resilient hybrid mass timber-steel structures are viable. This paper presents the specimen design and summarizes the preliminary results from the shake-table testing.
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- Award ID(s):
- 2120683
- PAR ID:
- 10632056
- Publisher / Repository:
- World Conference On Timber Engineering 2025
- Date Published:
- ISBN:
- 979-8-3313-2089-8
- Page Range / eLocation ID:
- 2473 to 2480
- Format(s):
- Medium: X
- Location:
- Brisbane, Australia
- Sponsoring Org:
- National Science Foundation
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