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According to a new design paradigm called Converging Design, high-level optimization objectives such as resilience and sustainability can be pursued through iterative simulation and feedback. Unlike traditional design processes that prioritize desirable seismic performance at various seismic hazard levels, the Converging Design methodology also considers the long-term ecological impact of construction and functional recovery. This methodology requires navigating competing priorities, which can be pursued through multi-objective optimization (MOO). However, computational costs and incorporating uncertainty in seismic analysis also demand that optimization frameworks use algorithms and analysis resolutions that are appropriate to the decisions being made as the design is refined. While such a framework could be applied to any material, mass timber systems are increasingly attractive as a potential sustainable solution for buildings. In this study, using a Python-based object-oriented program, an automated structural design procedure is developed to evaluate the seismic and sustainability performance of parametrically definable mass timber building configurations. Different geometric classes with Cross-Laminated Timber Rocking Walls are modeled using OpenSees and are automatically designed. Their behavior is then studied to provide insights into the relationship between structural variables and the optimization objectives. The results show a clear trade-off between Seismic Safety (the inverse of risk) and Global Warming Potential due to the construction of different design options, although the nature of this trade-off depends on the desired seismic behavior limit states. The developed software thus enables designers to efficiently explore a range of early design options for mass timber lateral systems and to achieve optimal solutions that balance seismic and sustainability performance. 

Twenty-five students over two years participated in an NSF GEOPATHs funded two-week, field-based summer research course and a follow up 15-week course-based undergraduate research experience (CURE). The goal was to attract, retain, and graduate a diverse group of students into an Environmental Geology program. Hispanic and female students were targeted for the cohorts, and 58% were female, 27% were Hispanic, and 8% were black. The students were split into two groups which worked in SW Florida. One group focused on surface water and groundwater in barrier islands and the other group studied calcite. Students in the surface water/groundwater group learned how to install temporary groundwater wells, collected groundwater and surface water samples, and analyzed water chemistry. Students in the calcite group learned how to collect field samples, prepare samples for analysis, and use advanced instrumentation to determine the calcite samples’ unit cells, atomic bonding, and classification. An attitude assessment, based on Lopatto (2010), was given at the end of both the summer and fall course. The students indicated that this research experience increased their confidence to conduct more research which occurs outdoors, help them identify as a scientist, and positively influenced their decision to major in Environmental Geology. Compared to the two-week summer program, survey results showed a slight decrease in students’ interest in the semester-long Fall course. Ninety six percent of the students indicated the SW Florida location caused them to be more invested in the research experiences, suggesting a sense of place was important to the students’ positive experiences during this project. Summer pre-test scores on summative assessments, based on Lewis et al. (2020), had a mean of 44% while the post-test had a mean of 68%. The Fall post-test mean increased to 88%. Paired t-tests for the summer and fall assessments show a statistically significant difference between the pre- and post-test scores. The students seemed to have a slightly more positive attitude towards research and geology as a result of the field experience, but their learning was higher after the semester-long CURE course. Fifty six percent of the cohort graduated with a degree in geoscience; 79% of the cohort currently have jobs in the geoscience sector or are attending graduate school the rest are still enrolled. 

Twenty-six students participated in an NSF GEOPATHs funded undergraduate research experience. This experience consisted of a two-week field-based summer research course and a follow-up 15-week course-based undergraduate research experience. The goal of this project was to attract, retain, and graduate a diverse group of students into a new Environmental Geology BS program. Hispanic and female students were targeted for the cohorts. 58% of our cohort were female, 27% were Hispanic, and 8% were black. The students were split into two groups. One group focused on barrier island groundwater in Southwest Florida and the other group studied calcite from Southwest Florida. Students in the groundwater cohort learned how to install temporary groundwater wells, collect groundwater and surface water samples, use probes and laboratory methods to measure water quality. Students in the calcite group learned how to collect and prepare samples for analytical work and use advanced instrumentation to determine the calcite’s unit cells, atomic bonding, and classification. Summative assessments based on Creative Exercises of Lewis et al. (2010) were given as pre- and post-tests during the summer field courses and again at the end of the fall course. A combined mean score for the summer pre-tests was 45%, while the fall post-tests score was 68%. A paired samples t-test for the combined summer assessment suggests a statistically significant difference between the pre- and post-test scores (t-score = 2.06; P = 2.55 x 10-6). An attitude assessment was based on Lopatto (2010) CURE survey and was given at the end of both courses. The students indicated this research experience increased their confidence to: conduct more research, and research with an outdoor component; help them identify as a scientist; and, positively influenced their decision to major in environmental geology. The students also indicated the location of the research experiences in Southwest Florida caused them to be more invested in the research. This suggests sense of place was impactful to the students’ positive experiences during this project. 

Mass timber products are gaining popularity in North America as an alternative to traditional construction materials as part of both the gravity and lateral force-resisting system. However, several knowledge gaps still exist in terms of their expected seismic performance and plausible hybridizations with other materials, e.g. steel energy dissipators. This research explores the potential use of wall spine systems consisting of mass ply panels (MPP) and steel buckling-restrained braces (BRBs) as energy dissipators. The proposed BRB-MPP spine assembly makes up the lateral force-resisting system of a three-story mass-timber building segment that will be tested under cyclic quasi-static loading at Oregon State University. The proposed design methodology follows displacement-based design principles to determine the minimum required stiffness to limit inelastic story drift ratios at the design earthquake level. The MPP spine and BRB-to-MPP connections were capacity designed to resist forces transferred by the BRBs at roof drift ratios beyond the risk-targeted Maximum Considered Earthquake (MCER). This design solution provides an interesting alternative for the design of modern mass timber buildings. The results obtained in the experimental campaign will be used to validate the design methodology and the behavior of the innovative structural system.