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1. Predetermined Collector Force and Rotation Histories Tests on TFW, in Advancing Knowledge on the Performance of Seismic Collectors in Steel Building Structures

   https://doi.org/10.17603/ds2-3wqg-aj61  

   Fleischman, Robert; Sause, Richard; Ricles, James; Pandey, Sudan; Marullo, Thomas (January 2026, Designsafe-CI)

   {"Abstract":["To safely survive an earthquake, and thereby protect its occupants, contents, adjacent property, and passersby, a building structure must transfer the large forces that develop during the earthquake from within the building down to the foundation. Earthquake (lateral) forces are generated by the building weight being accelerated horizontally, and thus most earthquake forces originate in the building's heaviest element, i.e., its floors. A key structural element in the force transfer path to the foundation are collectors, which are either special reinforcement in the floor slab or special beams below the slab, that "collect" the forces in the floor, and transfer them to the primary seismic force-resisting vertical elements (frames, braces, or walls). The loss of collectors or collector connections can be catastrophic, as evidenced by the collapse of the CTV building in the 2011 Christchurch, New Zealand earthquake, which killed 115 people, the largest loss of life in this event, and to some extent the collapse of nine parking garages in the 1994 Northridge, California earthquake. Despite the critical nature of seismic collectors, no research effort, including physical testing, has focused specifically on collectors, and knowledge of their seismic performance is lacking. A challenge in understanding the performance of seismic collectors is the complex nature of the floor system itself, a complicated assemblage of many components of different materials (e.g., steel, metal, and concrete) at different elevations, with multiple purposes and uncertain force paths. Past seismic design methodologies for buildings may have significantly underestimated the collector forces. This lack of knowledge impacts not only new construction but also the assessment and retrofit of existing, especially critical care, facilities in high seismic regions. This condition also applies to older non-seismic compliant steel structures nationwide, where inadequate or non-existent seismic collectors are often a major concern. A better understanding of the performance of steel seismic collectors is needed for safe and economical structures, both in the existing building stock and for new construction. Further, the collector's unique role as the critical link between the floor and the vertical elements provides an opportunity for collectors from trying to "out-strength" the earthquake force to instead serve as an innovative force-limiting element that protects the structure from damage. The goals of this research are to: (1) advance knowledge on the seismic performance, analysis, and design of collectors in steel composite floor systems, and (2) develop new knowledge on the reliable seismic performance and potential benefits of innovative collector concepts that can lead to low-damage structural design. This project will support researchers and graduate students from the University of Arizona, University of California, San Diego, and Lehigh University. The project will benefit from working closely with collaborators who are separately supported, i.e., a researcher and a practitioner in New Zealand and an industry panel of seismic design engineers in the United States. An outreach program will be conducted by the University of Arizona with local K-8 schools identified demographically as possessing student bodies of predominately underrepresented groups. The outreach program will target third, fourth, and eighth grade students to include: (1) slides shows and question and answer sessions on earthquake engineering, (2) career mentoring from graduate and undergraduate students, and (3) hands-on science and math activities.\n\nIn this project, an integrated research program will investigate the performance of seismic collectors for steel composite deck structures using the experimental and computational simulation capabilities afforded by the NSF-supported Natural Hazards Engineering Research Infrastructure (NHERI). The research will involve: (1) large-scale testing of collector elements in a steel composite floor system at the NHERI experimental facility at Lehigh University, (2) shake table testing of a 0.4-scale, single-story, steel composite floor system at the NHERI shake table facility at the University of California, San Diego, and (3) nonlinear analysis of steel structure collector elements, details and surrounding regions under seismic effects, and earthquake simulations of steel buildings under strong earthquakes. The planned experiments on steel collectors, with realistic boundary conditions and inertial forces, will be the first of its kind. New data products and calibrated numerical models will be produced from large-scale physical testing. Analytical models will be developed for the collectors and the collector inertial force paths. Transfer of research results into practice will include: (1) new concepts for low-damage structural design, (2) research-based design recommendations, and (3) assessment and retrofit guidelines."]} 

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2. Teacher Perspectives of Outcomes and Challenges Resulting from Students' Interactions with MATLAB in e4usa (Fundamental)

   Léger, N.; Klein-Gardner, S. S.; Berhane, B. T. (June 2023, 2023 ASEE Annual Conference & Exposition)

   As part of the e4usa curriculum, a MATLAB model has been developed and implemented in order to cultivate engineering and computational thinking skills in high school students. The MATLAB model uses a live script that allows students to interact with sliders and dropdown menus to change parameters on a water filtration model. With computational skills increasingly in demand, the literature suggests that adding computational thinking and coding skills as a new form of literacy is crucial for preparing future engineering professionals. Additionally, to ensure that students are better prepared by the time they reach their post-secondary studies, early exposure to computational thinking skills has valuable implications. In this fundamental paper, we describe outcomes resulting from students' interactions with MATLAB in e4usa. The mathematical model allows the students to analyze the effects of different filtration materials, impurities to be removed, length of the water filter, and the space between particles in their filtration material. Using at first a mathematical model rather than testing physical materials will allow them to learn more about their potential filtration materials so that they may make more informed decisions about which filtration materials they want to select for their design and use in the prototype that they build and test. With that said, we focus on student outcomes in this design activity. We hypothesize that this modeling activity prior to design may reduce the time spent in physical testing as well as the volume of materials consumed. Additionally, we are inquisitive about the impact that it has on the subsequent design activities compared to previous semesters where this lesson was taught, where it was observed that students spend a considerable amount of time trying out different materials. As part of our data, we have collected teacher data from surveys, pre and post-responses about their expectations, attitudes, and perceived value of implementing the MATLAB model in their classrooms, class observation data from at least two schools where we noted the interactions between the teachers and students, and teacher and student focus groups at the end of the semester where we expect to collect richer data from these two groups that will allow us to triangulate data collected from surveys and classroom observations. 

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3. Designing a Workshop to Support Teacher Customization of Curricula

   Bradford, Allison; Bichler, Sarah; Linn, Marcia C. (January 2021, Computersupported collaborative learning)

   de Vries, E; Hod, Y.; Ahn, J. (Ed.)

   We report on design-based research to refine a professional development workshop that supports teachers to customize online curricula. We iteratively design representations to make the knowledge integration pedagogy of the curricula visible. We study ways to make the work of students using the curricula actionable for participating teachers. We analyze participants’ trajectories across the three iterations of the workshop. Initially, when participants realized they could customize the online curriculum, they developed feelings of ownership. Then, as participants deepened their understanding of the pedagogy, they began to use it to evaluate their own instruction. The trajectory culminated in participants connecting the pedagogy to student work from their own classroom. This led to a shift from focusing on remedies for misconceptions to seeking opportunities for building on students’ nascent ideas when customizing. The workshop refinements empowered teachers to mobilize the pedagogy to interpret their students' work to inform their customization decisions. 

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4. What Are the Beliefs and Misconceptions about Climate Change of Students Pursuing Careers in Civil and Construction Engineering?

   Coleman, E.; Shealy, T.; Godwin, A. (April 2018, Construction Research Congress)

   The overwhelming consensus in the scientific community is that anthropogenic climate change will irreversibly affect future generations. Engineering professionals who design and construct our built environment can protect society against the effects of global warming through implementation of building strategies that reduce climate changing emissions. There is little research to assess if students who intend to pursue careers in the design and construction of our built environment hope to address such important environmental and societal challenges. To advance understanding, a survey instrument was developed and validated to measure undergraduate engineering students’ climate change literacy, career motivations, and agency to address climate change in their career. Preliminary results compare responses of engineering students intending to pursue a career in civil and construction industries to those of engineering students intending to pursue other engineering careers. The results indicate that civil and construction engineering students are more likely to take sustainability courses and learn about climate change in the classroom, but they do not excel above other engineers in their knowledge of climate science. The educational gap in engineering sustainability courses must be closed to ensure those who will design and construct our built environment are properly equipped to succeed in the sustainability-related careers they desire. 

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5. Coupon Material Testing:Subtitle

   https://doi.org/10.17603/ds2-k0db-er44  

   Duke, Jessica; Sause, Richard; Ricles, James; Cao, Liang; Marullo, Thomas (January 2022, Designsafe-CI)

   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. 

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