Natural Hazards Engineering Research Infrastructure: Large, High-Performance Outdoor Shake Table 2022-2025

The Natural Hazards Engineering Research Infrastructure (NHERI) is supported by the National Science Foundation (NSF) as a distributed, multi-user national facility to provide the natural hazards engineering research community with access to research infrastructure that includes earthquake and wind engineering experimental facilities, cyberinfrastructure (CI), computational modeling and simulation tools, high performance computing resources, and research data, as well as education and community outreach activities. Originally funded under program solicitations NSF 14-605 and NSF 15-598, NHERI has operated since 2015 through separate, but coordinated, five-year research infrastructure awards for a Network Coordination Office, CI, Computational Modeling and Simulation Center, and Experimental Facilities, including a post-disaster, rapid response research facility.

Information about NHERI resources is available at the NHERI web portal (https://www.DesignSafe-ci.org). Awards made for NHERI contribute to NSF's role in the National Earthquake Hazards Reduction Program (NEHRP) and the National Windstorm Impact Reduction Program (NWIRP). NHERI Experimental Facilities will provide access to their experimental resources, user services, and data management infrastructure for NSF-supported research and education awards.

This award will renew the operations of the large high-performance outdoor shake table (LHPOST) Experimental Facility located at the University of California, San Diego, to support research in structural and geotechnical earthquake engineering. The LHPOST was recently upgraded through NSF award 1840870 to six degrees-of-freedom (6-DOF) capabilities (LHPOST6) and can reproduce the surface ground motions resulting from major earthquakes, including the three translations and three rotations of the ground surface.

The shake table can support test structures with no height limitations and weighing up to 4.4 million pounds (20 meganewton). Building seismic-resilient and sustainable communities requires understanding and reliably predicting the seismic system-level response of buildings, critical facilities, utilities, lifelines, and other civil infrastructure systems.

The experimental research conducted on the LHPOST6, together with computational models making use of the datasets collected from shake table tests, will advance the science, technology, and practice in earthquake engineering, leading to next-generation design codes and decision-making tools that will increase the seismic resilience and sustainability of the built environment. Experiments performed at this facility will have a significant educational impact by providing life-size demonstrations of the seismic performance of structural, geotechnical, and soil-foundation-structural systems to graduate, undergraduate, and K-12 students from diverse backgrounds, and will also educate the public about the urgency of the nation’s efforts to develop effective technologies and policies to prevent natural hazards from becoming societal disasters.

The research activities will train next-generation researchers, educators, and practitioners, who will be future leaders in natural hazard mitigation. An active outreach program will include annual user training and industry-academia workshops, Research Experiences for Undergraduates, traditional and social media campaigns, webinars from users of the facility, and computational challenges competitions.

The LHPOST6 facility will transform natural hazard mitigation research by enabling large/full-scale system tests that will: (a) provide fundamental knowledge for understanding complete system behavior during earthquakes, from initiation of damage to the onset of collapse, including the effects of soil-foundation-structure interaction, the contributions of lateral and gravity load-resisting systems, and non-structural systems; (b) provide data for the development, calibration, and validation of high-fidelity physics-based computational models, therefore reducing future reliance on physical testing; (c) provide data and fragility information, which with validated simulation tools, will enable the full realization of performance-based design, the most rational/scientific way to evaluate and reduce the risks of natural hazards on the community; (d) provide validation tests for innovative structural systems and retrofit methods, as well as new materials, components, and manufacturing/construction methods for seismic protection; and (e) permit full-scale modeling of near-surface geotechnical systems and exploration of geotechnical phenomena and soil improvement techniques that cannot be explored at laboratory scale. The LHPOST6 will enable researchers to investigate the combined effect of realistic near-field translational and rotational earthquake ground motions on densely instrumented large/full-scale structural, geotechnical, or soil-foundation-structural systems, including the effects of kinematic and inertial soil-foundation-structural interaction, nonlinear soil and structural response, liquefaction, and seismic compression.

Experimental data produced by the testing at this facility will be archived and made publicly available in the NHERI Data Depot (https://www.DesignSafe-ci.org).

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.