The U.S. National Science Foundation (NSF) Natural Hazards Engineering Research Infrastructure (NHERI) Network Coordination Office (NCO) Education and Community Outreach (ECO) led coordinated efforts to promote educational activities along various pathways for students and educators targeted at broadening participation in and awareness of natural hazards engineering research through the Research Experiences for Undergraduates (REU) Summer Program, the Graduate Student Council (GSC), and the Summer Institute for Early Career Researchers and K-12 Educators. NHERI connects a diverse group of undergraduate and graduate students, faculty and K-12 educators, and researchers interested in mitigating the effects of natural hazards through these flagship educational programs. After 6 years of implementing these integrated educational activities, longitudinal outcomes and impacts for both students and faculty have been collected and are reported in this paper. Embedded in this report are several best practices used in educational outreach for recruitment, mentoring, and engagement of diverse participants that have been evaluated and enhanced through assessment and in collaboration with the larger NHERI network. Throughout 6 years of leading education activities, these practices have also helped create an intentional focus on challenge areas and informed the evolution of interdisciplinary pathways for natural hazards engineering research.

The transition from industry to academia can present unique challenges for new faculty members in STEM (Science, Technology, Engineering, and Mathematics) fields. Considering high drop, fail, withdraw (DFW) rates in undergraduate STEM courses and the need to increase the number of well-prepared graduates in these areas, it is important to better understand the needs of early-career faculty transitioning from outside of academia in order to support their development as effective scholars and educators. This study, which utilizes a Scholarship of Teaching and Learning (SoTL) framework, focuses on the experiences, views, and needs of two engineering faculty members who have recently moved from industry to academia. Findings inform practice and indicate a common lack of knowledge about new faculty’s teaching requirements, a need for personalized support structures for incoming faculty members, and a shift toward active approaches to teaching students when such supports are provided. In this process, leveraging an embedded experts model and acknowledging and understanding students’ needs through active listening emerged as important factors in faculty’s growth and personal development during their first semester in academia.

Fusion bonded thermoset epoxy-coated reinforcement is evaluated in conjunction with inorganic and organic corrosion inhibitors, bars initially coated with zinc prior to epoxy application, chemical pretreatments and epoxy formulations that increase the adhesion of the epoxy coating, and concretes with reduced water-cement ratios. The performance of corrosion protection systems is compared based on metal loss and disbondment between the epoxy-coating and the underlying steel using Southern Exposure and cracked beam tests in the laboratory and larger-scale slab specimens in the field. Findings after six years of this seven-year study indicate that conventional epoxy-coatings provide significant corrosion protection for reinforcing steel. The main potential weakness of this system is the loss of adhesion between the epoxy coating and the reinforcing steel, which is observed to be significantly greater for bars in cracked concrete than for bars in uncracked concrete. Bars initially coated with zinc prior to epoxy application exhibit lower disbondment than conventional epoxy-coated reinforcement. Concretes with reduced water-cement ratios provide better performance in uncracked concrete but only limited additional corrosion protection in cracked concrete.

Contribution: This study extends the embedded expert literature by examining a cross-college partnership between engineering and education faculty and its impact on the engineering faculty’s teaching practices. Background: Previous embedded expert models focused on disciplinary expert models that required extensive educational training to prepare embedded experts to work with instructors to transform courses using active learning strategies. Intended Outcomes: This study employed a novel approach to the embedded expert model by utilizing science, math, and technology education faculty to support undergraduate engineering instructors in transforming teaching practices. Active learning strategies and culturally relevant pedagogy were emphasized in this multisemester transformation process. Anticipated outcomes included decreases in the drop, withdrawal, and failure rates in transformed courses, and an increase in overall GPA for students enrolled in these courses. Application Design: The embedded educational expert approach supported instructors in electrical engineering, biomedical engineering and academic inquiry scholarship, and chemical engineering. Course interventions included adaptive assessment, project-based learning (PBL), peer-assisted learning, and case studies. Findings: Observation, interview, survey, and course level support the multidisciplinary embedded expert model for transforming instructors’ teaching practices and improving student pass rates within multiple engineering departments.

Vittorio Marone is an Associate Professor of Instructional Technology in the Department of Interdisciplinary Learning and Teaching at The University of Texas at San Antonio. He earned his doctorate in Education in a dual-degree program between the University of Padua and The University of Tennessee. He also holds a doctorate in Languages, Cultures, and Societies from Ca’ Foscari University of Venice. His research interests include new literacies, youth cultures, games and learning, music technology, and multimodality. He presented his work at national and international conferences such as GLS (Games + Learning + Society) and G4C (Games for Change). He is the author of the book La Quotidianità dell’Assurdo (The Everyday Absurd, Archetipolibri, Bologna, 2010).

Since 2015, NHERI, or the Natural Hazards Engineering Research Infrastructure, began research operations supported by the United States National Science Foundation (NSF) as a distributed, multi-user national facility that provides the natural hazards research community with access to a powerful research infrastructure. NHERI is comprised of separate research infrastructure awards for a Network Coordination Office (NCO), Cyberinfrastructure, a Computational Modeling and Simulation Center, eight Experimental Facilities, and CONVERGE (an initiative to advance social sciences and interdisciplinary research). Awards made for NHERI contribute to NSF's role in the National Earthquake Hazards Reduction Program and the National Windstorm Impact Reduction Program of the United States. The mission of NHERI is to provide the earthquake, wind, coastal engineering, and social sciences communities with access to research infrastructure, education, and community outreach activities focused on improving the resilience and sustainability of the civil infrastructure against earthquakes, windstorms, and associated natural events such as tsunami and coastal storm surge. In this paper, the role and key NHERI activities are described for the NCO, which is led by Purdue University, along with partner institutions—the University of Texas at San Antonio, North Carolina State University, Texas Tech University, the U.S. Naval Research Laboratory, and the University of Hawaii at Manoa. The NHERI NCO serves as a focal point and leader of a multi-hazards research community, and maintains a community-based NHERI science plan. It manages scheduling for partner NHERI Experimental Facilities and coordinates all components to ensure effective and fair governance, efficient testing, and user support within a safe environment. Another important role of the NCO is to lead NHERI-wide educational and outreach activities: the network facilitates educational experiences ranging from summer programs for undergraduates to workshops for post-docs and early-career faculty that also both involve development of K-12 lesson plans. The NCO works to develop strategic national and international partnerships and to coordinate NHERI activities with other awardee components to form a cohesive and fully-integrated global natural hazards engineering research infrastructure that fosters collaboration in new ways.

Engaging engineering faculty in transformative practices in course design and teaching is critical to student success, especially in fields like engineering where there are challenges with attrition and retention. This paper presents a current course transformation program in which engineering faculty transform the design of their courses and teaching practices to improve learning supported by embedded experts. In this program, embedded experts are education experts who work with engineering faculty in transforming courses to address the needs of their students. This evaluation study investigates the outcomes of course transformations on engineering student achievement and teaching practices. The results show an overall improvement in student achievement outcomes and indicate that it has helped participating faculty become more successful engineering educators.

Corrosion-related cracking in reinforced concrete is caused by expansive corrosion products and the resulting tensile stresses. While the amount of corrosion to cause cracking has been studied for uncoated conventional reinforcement, significantly less is known about the corrosion loss at cracking for galvanized reinforcement. Conventional and galvanized bars were cast in chloride-contaminated concrete. Clear cover to the bar ranged from 0.5 to 2 in. (12.7 to 51 mm). Specimens were tested both with and without the use of impressed current to drive corrosion. It was found that galvanized reinforcement requires greater corrosion losses to crack concrete than conventional steel reinforcement. Visual observations at autopsy suggest that the cracking of the concrete specimens containing galvanized reinforcement was not due to zinc corrosion products, but rather to corrosion products from intermetallic iron-zinc layers or from the underlying steel. Further study is needed to determine the exact nature of these corrosion products. Tests using impressed current may be used to establish the corrosion loss required to cause cracking.

XM-28 (UNS S24100) and 2304 (UNS S32304) stainless steel reinforcing bars with different levels of pickling were evaluated for corrosion resistance using the rapid macrocell and cracked beam tests outlined in ASTM A955. Two heats of XM-28 from the same producer were evaluated using the rapid macrocell test. A single heat of 2304 was evaluated in two conditions; as-received from the manufacturer and re-pickled using both ASTM A955 tests. The poorly pickled heat of XM-28 reinforcement failed the rapid macrocell test with a peak individual corrosion rate exceeding 16 mu m/y, while the properly pickled heat passed with no significant corrosion measured. The poorly pickled 2304 reinforcing steel failed the macrocell and cracked beam tests, with peak corrosion rates of 1.07 and 6.48 mu m/y, respectively, while upon re-pickling, the same heat of steel passed both tests. These results suggest the need for a method to verify that the pickling process has been performed properly. Performance during the first week of the rapid macrocell tests or requiring that the bars exhibit a bright, shiny, uniformly light surface represent two potential methods for establishing the adequacy of pickling.

This paper presents a work in progress of our university's initiative aimed at improving undergraduate engineering education through faculty professional development. This professional development is based on continual mentoring and course transformation through embedded education experts paired with engineering faculty. Through such transformative teaching practices, this initiative seeks to increase student achievement, interest, and retention in engineering, particularly with students from underrepresented minority groups.

Anti-bleed grouts are often used to fill voids in post-tensioning ducts that result from bleeding and shrinkage of older portland-cement grouts. This repair however exposes the strands to environmental differences from dissimilar grouts, differences that may cause rapid corrosion. Portland-cement grout, gypsum grout, and four commercially available prepackaged grouts were analyzed to determine the chemical composition of the resulting pore solutions and tested to determine the potential for accelerated corrosion. Grouts and simulated pore solutions were paired to. evaluate their potential to cause corrosion of respectively, grout-encased and bare prestressing strands using the rapid macrocell test. Strands were also evaluated in simulated pore solutions containing chlorides and in deionized water Unprotected prestressing strands can exhibit rapid corrosion. Gypsum grout, with its low pH and high sulfate content, will cause accelerated corrosion of strands when used in conjunction with any of the other grouts tested. None of the prepackaged grouts resulted in significant corrosion when used in conjunction with portland-cement grout. The highest corrosion measured for a prepackaged grout occurred for the grout with the highest pore solution sulfate content.

The effect of a partial replacement of cement with slag cement on free shrinkage is evaluated for curing periods between 3 and 28 days. Mixtures include concrete containing different replacement levels of slag cement (30, 60, and 80% by volume) cast with limestone, granite, or quartzite coarse aggregate. Comparisons are only made with mixtures having the same paste content (by volume) and water-cementitious material ratio. The study shows that a partial replacement of cement with slag cement decreases free shrinkage compared to mixtures containing 100% portland cement; the reduction is greatest at early ages and is improved as the replacement level is increased. Increasing the curing period decreases free shrinkage for mixtures with and without slag cement. When slag cement is used in conjunction with a porous limestone coarse aggregate, where internal curing is provided by the water stored in the pores of limestone, an even greater reduction in free shrinkage is observed compared to mixtures cast with low-absorption coarse aggregate.

The bond strength of four sets of reinforcing bars is evaluated, two each with No. 5 and No. 10 (No. 16 and No. 32) bars, which have, respectively, nominal diameters of 0.625 and 1.27 in. (15.9 and 32.3 mm). One bar of each size satisfies the criterion for maximum deformation spacing in ASTM reinforcing bar specifications, while the other has deformations that exceed the maximum spacing. All bars exceed the requirements for minimum deformation height. Research related to the effect of deformation properties on bond strength, including the research used to establish the requirements for deformations in ASTM reinforcing bar specifications, is also reviewed. The test results match earlier research and demonstrate that (1) bond strength is not governed by the specific value of deformation height or spacing, but by the combination of the two as represented by the relative rib area of the bars and (2) the bond strength of the bars with deformation spacings that exceed those in ASTM reinforcing bar specifications is similar to the bond strength of the bars that meet the specification. Based on this and prior research, it is recommended that ASTM reinforcing bar specifications be modified to allow for deformation spacing up to 90 % (currently a maximum of 70 %) of the bar diameter provided the ratio of deformation height to deformation spacing is greater than or equal to the minimum ratio for bar deformations meeting the current requirements in ASTM reinforcing bar specifications.

The implementation of a step-by-step concrete mixture design procedure to determine an optimized aggregate gradation is described. The procedure uses both the modified coarseness factor and percent retained charts to establish an optimal blend of user-selected aggregates, criteria that are usually not implemented simultaneously. The design process is iterative and depends on the gradations of available aggregates, the cementitious material content of the concrete mixture, and the maximum aggregate size. The procedure can be implemented using a spreadsheet and, unlike traditional approaches, is capable of blending aggregates with significantly different specific gravities.

Bridge deck crack surveys were performed on twelve bridges on US-59 south of Lawrence, Kansas, to determine the effects of mixture proportions, concrete properties, deck type, and girder type on the crack density of reinforced concrete bridge decks. Of the twelve decks surveyed, eight are supported by prestressed concrete girders and four are supported by steel girders. Four of the decks supported by prestressed girders are cast on partial-depth precast deck panels, two are monolithic with synthetic fibers, and two have overlays. Of the four decks supported by steel girders, two have silica fume overlays (SFO) and two are monolithic. One of two decks with a silica fume overlay contains synthetic fibers in the overlay. Following the surveys, crack maps were plotted and analyzed and cracking trends were observed. The results for the US-59 bridge decks are compared with crack densities obtained in a study of low-cracking high-performance concrete (LC-HPC) bridge decks. The monolithic concrete bridge decks supported by prestressed concrete girders within this study exhibit less cracking than decks supported by steel girders. At an age of approximately three and a half years, the US-59 monolithic decks supported by prestressed girders with deck panels are not displaying significant cracking; most of the cracks are short transverse cracks aligned with the joints between the deck panels. The US-59 decks supported by prestressed girders with overlays exhibit significantly more cracking than the decks on prestressed girders without overlays. Bridge decks supported by steel girders without overlays have slightly higher crack densities than the decks with overlays. No benefits of using fibers in either the overlay or deck have been observed in this study, the sample size, however, is small. An increase in crack density was observed with an increase in average concrete slump for decks supported by both prestressed and steel girders. Decks with deck panels supported by prestressed girders exhibited an increased crack density with an increase in paste content. .

A high-resolution model of a bridge column was developed using the computer program ABAQUS, and the accuracy of the model was evaluated for the displacement field and the rotations of a bridge system subjected to biaxial shake-table loading. The effect of simulation parameters (reinforcing bar slip within the joint and stiffness degradation of the concrete) was studied to determine the goodness-of-fit of the displacement and rotation fields recorded during the dynamic response. Fourier Domain Error Index analyses showed that the yield stress of the reinforcement and the boundary conditions of the column submodel were important parameters, and the damage and stiffness degradation parameters were not as important for the goodness-of-fit of the finite element model. The computed rotations at the plastic hinge regions near the beam caps had the best correlation.

The corrosion performance of 2304 duplex stainless steel reinforcement and NX-SCR™ stainless steel clad reinforcement was tested using the rapid macrocell, Southern Exposure, and cracked beam tests. The 2304 duplex stainless steel was evaluated in the as-received condition and after re-pickling in the macrocell tests. The NX-SCR™ stainless steel clad reinforcement was evaluated in the undamaged and damaged (0.83% damaged area) conditions and without a cap to protect the inner conventional steel core in the rapid macrocell test, in the undamaged condition in the Southern Exposure and cracked beam tests (known as bench-scale tests), and in the damaged condition (0.2% damaged area) in the Southern Exposure tests, and as a bent bar in the rapid macrocell and Southern Exposure tests. The performance of both steels was compared with that of epoxy-coated reinforcement in the damaged (0.83% damaged area for macrocells, 0.5% damaged area for bench-scale) and undamaged conditions and with conventional reinforcing steel. Tests of mixed specimens containing both stainless steel and conventional bars as either the anode or the cathode to evaluate possible galvanic effects were also performed. For specimens that initiated corrosion, the chloride content at the level of top reinforcement in the Southern Exposure specimens was also measured at the time of corrosion initiation. The results of the rapid macrocell and cracked beam tests are used to evaluate the stainless steel bars in accordance with the requirements of ASTM A955. For stainless steels to qualify in accordance with the rapid macrocell test guidelines listed in ASTM A955, the corrosion rate of the individual specimens may not exceed 0.50 μm/yr, and the average corrosion rate for all specimens in a series may not exceed 0.25 μm/yr.