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Student understanding of climate change is an active and growing area of research, but little research has documented undergraduate students’ knowledge about the biotic impacts of climate change. Here, we address this literature gap by presenting the Inventory of Biotic Climate Literacy (IBCL), a concept inventory developed to assess undergraduate biology student knowledge of how climate change impacts living things. We developed the IBCL through literature review, student and expert interviews, student field tests, and expert review. We implemented two large nationwide field tests and conducted multiple psychometric analyses on these datasets. These analyses resulted in a final tool of 30 items measuring 16 constructs related to the biotic impacts of climate change. We discovered that the final IBCL does not represent a single, simple construct but rather the complicated and interactive concepts that comprise this topic. We suggest that sum scores are still a valuable measure, as certain groups (upperclassmen and politically liberal individuals) scored significantly higher. We also found value in analyzing individual student performance on the IBCL by developing student profiles. The IBCL represents an important tool in assessing student understanding of the complex and growing problem of climate change and its impact on the living world. 

This project will develop a new structural system that will protect buildings, their contents, and occupants during large earthquakes and will enable immediate post-earthquake occupancy. This earthquake-resilient structural system will be particularly valuable for essential facilities, such as hospitals, where damage to buildings and contents and occupant injuries must be prevented and where continuous occupancy performance is imperative. The new system will use practical structural components to economically protect a building from damaging displacements and accelerations. The project team will collaborate with Japanese researchers to study the new system with full-scale earthquake simulations using the 3D Full-Scale Earthquake Testing Facility (E-Defense) located in Miki, Japan, and operated by the National Research Institute for Earth Science and Disaster Resilience. This project will advance national health, prosperity, and welfare by preventing injuries and loss of human life and minimizing social and economic disruption of buildings due to large earthquakes. An online course on resilient seismic design will be developed and offered through the American Institute of Steel Construction night school program, which will be of interest to practicing engineers, researchers, and students across the country. This project contributes to NSF's role in the National Earthquake Hazards Reduction Program. The novel steel frame-spine lateral force-resisting system with force-limiting connections (FLC) that will be developed in this project will control multi-modal seismic response to protect a building and provide resilient structural and non-structural building performance. This frame-spine-FLC system will rely on a conventional, economical base system that resists a significant proportion of the lateral load. The system judiciously employs floor-level force-limiting deformable connections and an elastic spine to protect the base system. Integrated experiments and numerical simulations will provide comprehensive understanding of the new frame-spine-FLC system, including rich full-scale experimental data on building seismic performance with combined in-plane, out-of-plane, and torsional response under 3D excitation. The FLCs will be tested using the NHERI facility at Lehigh University. This project will be conducted in collaboration with an ongoing synergistic research program in Japan. The extensive dataset from this integrated U.S.-Japan research program will enable unique comparisons of structural and non-structural performance, including critical acceleration-sensitive hospital contents that directly affect the health and safety of patients. In addition, the dataset will enable the advancement of computational modeling for the assessment of building performance and the development of practical, accurate models for use in design that capture the complex 3D structural response that occurs during an earthquake. 

This project will develop a new structural system that will protect buildings, their contents, and occupants during large earthquakes and will enable immediate post-earthquake occupancy. This earthquake-resilient structural system will be particularly valuable for essential facilities, such as hospitals, where damage to buildings and contents and occupant injuries must be prevented and where continuous occupancy performance is imperative. The new system will use practical structural components to economically protect a building from damaging displacements and accelerations. The project team will collaborate with Japanese researchers to study the new system with full-scale earthquake simulations using the 3D Full-Scale Earthquake Testing Facility (E-Defense) located in Miki, Japan, and operated by the National Research Institute for Earth Science and Disaster Resilience. This project will advance national health, prosperity, and welfare by preventing injuries and loss of human life and minimizing social and economic disruption of buildings due to large earthquakes. An online course on resilient seismic design will be developed and offered through the American Institute of Steel Construction night school program, which will be of interest to practicing engineers, researchers, and students across the country. This project contributes to NSF's role in the National Earthquake Hazards Reduction Program. The novel steel frame-spine lateral force-resisting system with force-limiting connections (FLC) that will be developed in this project will control multi-modal seismic response to protect a building and provide resilient structural and non-structural building performance. This frame-spine-FLC system will rely on a conventional, economical base system that resists a significant proportion of the lateral load. The system judiciously employs floor-level force-limiting deformable connections and an elastic spine to protect the base system. Integrated experiments and numerical simulations will provide comprehensive understanding of the new frame-spine-FLC system, including rich full-scale experimental data on building seismic performance with combined in-plane, out-of-plane, and torsional response under 3D excitation. The FLCs will be tested using the NHERI facility at Lehigh University. This project will be conducted in collaboration with an ongoing synergistic research program in Japan. The extensive dataset from this integrated U.S.-Japan research program will enable unique comparisons of structural and non-structural performance, including critical acceleration-sensitive hospital contents that directly affect the health and safety of patients. In addition, the dataset will enable the advancement of computational modeling for the assessment of building performance and the development of practical, accurate models for use in design that capture the complex 3D structural response that occurs during an earthquake. 

Specimen 2 was created to combat some of the issues found from the static testing of Specimen 2. The base dimension was increased from 1.5” to 2”. The width of the cantilever was also decreased to increase the flexibility of the element. Static testing of Specimen 2 revealed that the element flexibility was increased to achieve a stiffness of 83 k/in resulting in larger post-yielding deformation. Yielding occurred in the cantilever area only. 

Numerical modeling is widely used in structural engineering to represent buildings response under seismic loading conditions. However, even though numerical modeling is a common tool to characterize the behavior of structures, modeling uncertainties can lead to a broad range of expected response, particularly when representing the behavior of novel systems or components. Addressing different modeling choices can provide more informed insights into the response of structures, especially prior to conducting experimental tests or participating in blind prediction contests. Herein, blind response prediction of a novel steel system was conducted before testing at the E-Defense facility in Japan. The full-scale specimen consisted of a weak Moment-Resisting Frame (MRF) retrofitted with steel spines and force-limiting connections (FLC). The set of pre-test predictions involved addressing of different modeling choices to overcome the many sources of epistemic uncertainties and to provide greater confidence in the design and experimental testing program. Several models were subjected to the records specific to the testing program (Northridge Sepulveda and JMA Kobe) to estimate drift and acceleration responses. Numerical results were compared to the experimental data from the shake-table tests. Although all the models were able to represent general trends in drifts and accelerations and enabled proper development of the testing plan, peak response varied significantly depending on the modeling choices, especially those altering the system’s natural periods or those leading to different yielding patterns. 

A new seismic-resilient structural system is being developed to protect buildings, their contents, and occupants during major earthquakes. This economical system is intended for essential facilities, such as hospitals, where damage to the buildings and contents and occupant injuries must be prevented and where continuity of operation is imperative. The primary components of the Frame-Spine-FLC System are: (1) steel base moment-resisting frames designed and detailed to behave in the inelastic range and dissipate energy, (2) stiff and strong elastic spines designed to remain essentially elastic to redistribute seismic demands more uniformly over the building height, and (3) force-limiting connections (FLC) that connect the frame to the spines to provide a yielding mechanism that limits acceleration demands. An international team, including three U.S. universities, two Japanese universities and two major experimental research labs, is collaborating on this project and recently conducted full-scale shake-table testing at the E-Defense facility in Miki, Japan. The test building represents a hospital facility and includes realistic nonstructural components and medical equipment. This paper provides an overview of the shake-table testing program and presents preliminary results that demonstrate the seismic stability response of the Frame-Spine-FLC System and the overall viability of the new concept. 

Abstract In light of the significant damage observed after earthquakes in Japan and New Zealand, enhanced performing seismic force‐resisting systems and energy dissipation devices are increasingly being utilized in buildings. Numerical models are needed to estimate the seismic response of these systems for seismic design or assessment. While there have been studies on modeling uncertainty, selecting the model features most important to response can remain ambiguous, especially if the structure employs less well‐established lateral force‐resisting systems and components. Herein, a global sensitivity analysis was used to address modeling uncertainty in specimens with elastic spines and force‐limiting connections (FLCs) physically tested at full‐scale at the E‐Defense shake table in Japan. Modeling uncertainty was addressed for both model class and model parameter uncertainty by varying primary models to develop several secondary models according to pre‐established uncertainty groups. Numerical estimates of peak story drift ratio and floor acceleration were compared to the results from the experimental testing program using confidence intervals and root‐mean‐square error. Metrics such as the coefficient of variation, variance, linear Pearson correlation coefficient, and Sobol index were used to gain intuition about each model feature's contribution to the dispersion in estimates of the engineering demands. Peak floor acceleration was found to be more sensitive to modeling uncertainty compared to story drift ratio. Assumptions for the spine‐to‐frame connection significantly impacted estimates of peak floor accelerations, which could influence future design methods for spines and FLC in enhanced lateral‐force resisting systems.