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Abstract Distribution of bed shear stress is the critical factor in regulating the meandering of single-thread rivers. However, the impact of ice cover on bed shear stress is largely unknown. In this study, we develop a theoretical model of cross-stream momentum balance to examine the distribution of bed shear stresses in ice-covered meandering rivers. To validate the theoretical model, field surveys were carried out in a river reach of the Red River in Fargo, North Dakota. Data monitoring was completed using an Acoustic Doppler Current Profiler to obtain time-averaged velocity profiles. Our theoretical model indicates that an ice covering develops high-shear zones near both the inner and outer banks, which might exacerbate sediment transport and enhance bank erosion. Velocity measurements confirm the results of the proposed model and demonstrate a clear impact of meandering river banks on velocity profiles and secondary flow patterns under ice cover. Based on our results, we hypothesize that ice cover increases turbulent stresses near banks, which in turn lead to the enhancement of the bed shear stress. Our work provides new insights into the impact of ice cover on bed shear stress distribution, which could play an important role in driving sediment-transport processes and the long-term morphodynamic evolution of meandering rivers seasonally covered by ice. 

National Science Foundation (NSF) funded Research Experiences for Teachers (RET) programs provide opportunities for professional development for teachers. The goal of the RET site at North Dakota State University (NDSU), established in May 2020 (NSF Awards #1953102 and #2224135), was to increase the knowledge of secondary (6th to 12th grade) educators in the use of civil engineering to mitigate natural disasters and their ability to prepare their students to become leaders in STEM disciplines. The primary goal of this study is to assess the effectiveness of the professional development provided in preparing participants to teach STEM topics in their classrooms. The study utilized a mixed method approach and an external evaluator to present data on the responses to two online surveys and a self-interview conducted with the secondary educators in the Summer 2021 NDSU RET cohort. Three themes emerged: (1) difficulty with math, (2) lack of connection/examples, and (3) issues with open-endedness and time to get a response. Nearly all the teachers noted that experiments and simulations with data were helpful strategies in engaging their students in STEM topics. They found value in connecting these topics with real-world problems in the student’s lives. Teachers had increased knowledge about the research projects, real-world applications, and other ways to engage their students in STEM (specifically, civil engineering). Their knowledge was further increased by their interactions with other teachers in the RET program as well as through the presentations that the other teachers delivered during the summer activities. 

Students act as civil engineers and use the engineering design process to design and construct a building in an earthquake-prone area for a local developer. Students will have to make decisions on how many materials they use, because they will have a budget to meet. The building materials will include spaghetti noodles, toothpicks, flexible straws, marshmallows, and hot glue. They will also have to construct a building with specific size constraints and that can withstand a 2.5 lb. weight being placed on top of it. After construction, their building with the weight will be placed on a shake table. Students will measure the time their building remains standing during the earthquake. Students will review where their building first collapsed and redesign their building to try to make it last longer in a second earthquake. Finally, each group will use all of their information to develop a presentation of their results for the developer in hopes of winning the bid. 

Students act as environmental engineers to solve a problem using carbon dioxide (CO2) emissions from cars and wildfires. Wildfires are a timely topic because every year they cause people in many areas to face poor air quality. Students use Microsoft Excel to investigate CO2 emitted from two sources: highway traffic and forest fires. They estimate and graph the CO2 emitted by forest fires and from U.S. highway driving annually from 2004 to 2021. After they analyze these two pieces of data, they analyze a specific fire and evacuation that happened in Saratoga Springs in June 2020, named the Knolls Fire. Finally, using the Excel data and the Knolls Fire data, students decide whether the U.S. should spend money on reducing the number and severity of wildfires, or on reducing CO2 emissions from driving cars. The students design and create a poster based on their decision and present it to the class. 

Students learn how seasonal flooding from snowmelt affects rivers and evaluate how changing environmental conditions, such as flood levels and temperatures, influence the distribution and abundance of organisms such as mosquitoes. In this hands-on activity, students build a river model using stream tables to explore the factors that affect water flow and velocity. Using what they learn, students predict how flooding impacts mosquito populations. Finally, they develop a vector control strategy to reduce mosquito populations and help prevent the spread of mosquito-borne diseases. 

Students act as civil engineers who are assessing the viability of a new housing development along a river. Students use a map of the river and the location of the proposed development to demonstrate where erosion and deposition are occurring along the river. They interpret precipitation data to determine whether flooding will occur. Finally, they create a presentation that includes the best course of action for the city and any flood mitigation strategies necessary. 

A total of 66,894 landslides were observed in North Dakota. The characteristics of these landslide locations were compared with the properties of areas without landslides to assess the factors that may be contributing to the landslides. Specifically, 68,395 control point locations randomly distributed across the state were selected for these comparisons. All the landslides for this study were found in areas with slopes less than 64°, with the majority of the failures occurring on slopes with inclinations between 9° and 14°. The largest fraction of the landslides occurred in the Sentinel Butte Formation (34,063 or 51% of the total), followed by Bullion Creek (8695 or 13% of the total) and river sediment of the Oahe Formation (6421 or 9.6% of the total). In the t tests, all of the surficial geologic formations had statistically significant differences between the landslides and control points. The t test for the slope inclination indicated statistically significant differences with a p-value less than 0.001 and a huge effect size between the landslide and control points. The sodium adsorption ratio and total dissolved solids were also found to be statistically significant from the t test results. Pearson’s correlation matrix showed a negative correlation between the amount of rainfall and various measures of the salt concentrations at the landslide locations, pointing to the reductions in shear strength and slope stability that might result as pore fluid salinity is leached. 

High school science and math classes can often seem irrelevant to the everyday lives ofstudents leading to difficulties in engaging students in these topics. Moreover, limitedopportunities for hands-on learning can further perpetuate perceptions of subject matter difficultyand result in limited exposure to available career paths. By incorporating hands-on curriculummodules in geotechnical engineering, it is possible to overcome these issues while providingstudents with real-world applications making the material more engaging and meaningful. Thispaper presents two curriculum modules developed as part of the National Science Foundation-funded Research Experiences for Teachers (RET) site at North Dakota State University. Thesemodules—one for a high school science class and one for a high school math class—weredeveloped with the aim of promoting science, technology, engineering, and mathematicseducation (STEM), while inspiring students to consider careers in geotechnical engineering. Thelessons are designed to align with the Next Generation Science Standards and include hands-onactivities along with real-world applications to enhance student understanding of the subjectmatter. The effectiveness of these modules was evaluated through formative and summativeassessment and student surveys. The results indicate that the modules can effectively engagestudents in geotechnical engineering by connecting the math and science concepts from theirclasses and increase their interest in STEM fields. These curriculum modules are a valuableresource for high school math and science teachers looking to integrate engineering into theirclasses. 

Fine-grained soils subjected to seismic loading often exhibit instability or failure of slopes, foundations, and embankments. To understand the behavior of clay soils under multiple earthquake loads, kaolinite samples were prepared and tested in the laboratory using a cyclic simple shear device. Each sample was subjected to two cyclic events separated by different degrees of reconsolidation periods to simulate different levels of excess pore water pressure dissipation. The results indicated that the degree to which excess pore water pressure generated during the first cyclic event was dissipated affected the cyclic resistance of the soil during the second cyclic event. The post-cyclic undrained shear strength was also found to be a function of the degree to which excess pore water pressure from the first cyclic load was allowed to dissipate prior to the application of the second cyclic load. 

Through funding from the National Science Foundation to create a Research Experience for Teachers site at North Dakota State University, the authors provided summer research experiences to current secondary (6th to 12th grade) educators to improve their understanding of the civil engineering field and develop new curriculum modules for their classrooms. Reflection of the first summer program in 2021 highlighted several modifications that could be made to improve the quality of the program and curriculum developed, increase the accessibility to underserved and/or underrepresented populations and to better utilize the limited resources available. This paper summarizes the successes of the RET program and provides several concrete recommendations for future programs. Specifically, recruiting of both teachers and faculty could be more effective when personal communications through known contacts are used. Flexibility in the approach without compromising rigor and expectations allows for a more inclusive program that supports underserved and marginalized populations.