The Napkin Sketch Pilot Study: A minute-paper reflection in pictorial form

This paper presents an evidence-based practice pilot study of the potential cognitive benefits of requiring students to create sketches that summarize course material in ways different than presented in class. This exercise is termed a “napkin sketch” to articulate to students the benefits of simple sketches to communicate ideas – as is often done by engineers in practice. The purpose of the study was to investigate how this napkin sketch activity addresses three concerns of engineering educators: creativity, visualization and communication, and knowledge retention. Specific objectives of the study were to generate conclusions regarding the activity’s ability to (1) provide an outlet for, and a means of encouraging creativity, (2) provide an opportunity for students to visualize and communicate what they have learned through drawings rather than equations or writing, and (3) encourage knowledge retention by providing a mechanism for students to think about and describe concepts learned in the classroom differently than for other requirements. The scope of this paper includes the generation, implementation, and analysis of the napkin sketch activity in three civil engineering courses across eight different class sections in the spring and fall of 2019 at the U.S. Military Academy, a small, public, undergraduate-only four-year college in the northeast United States. The motivation for the study stems from evidence-based practices of re-representation from educational psychology, minute papers from educational research, the growing shift to computer-aided design and away from hand drawing, and recent research suggesting our engineering programs may be degrading student creativity. A between-subjects quasi-experimental setup examined four activity implementations and 249 sketches were collected. Sketch creativity was assessed by three instructors using a creativity rubric adapted from literature. The sketch creativity scores, along with individual student academic and course performance data, were analyzed using standard least squares regression and machine learning techniques to investigate the effect of sketching on creativity and understanding of course material. An anonymous and optional survey was also provided to a total of 56 students, with 21 students responding (37.5%). The following key conclusions can be drawn from the study: (1) the activity does encourage students to think about the material differently, and provides a means for creative students to express lesson content creatively; however, assessment bias, selection bias, and the inherent difficulty in assessing creativity does not allow us to draw conclusions about the creativity of engineering students in any absolute sense from the collected data; (2) incorporating an emphasis on freehand sketching into the engineering curriculum could have positive effects toward developing creativity and pictorial communication skills; (3) there was evidence in the data suggesting that the sample populations examined in the study are experiencing degradation in creativity between sophomore and senior level coursework, which was an idea expressed in the literature; (4) the sketch creativity scores are higher when it is conducted after blocks of material and performed outside of class

Design and Implementation of a New Retrofit for Prestressed Concrete Bridge Elements Using Mechanically-Fastened Fiber-Reinforced Polymer

Currently, departments of transportation (DOTs) must post load restrictions or closures on bridges with deteriorated prestressed concrete superstructures that can no longer carry original design loads. These posted restrictions and closures result in detours that increase travel time and vehicle operating costs for detoured vehicles, impacting commerce, public transportation, and emergency services. Often, load restrictions and closures must remain in place for several years to allow for budgeting, design, and contracting cycles prior to scheduling and completion of permanent repairs or superstructure replacement which must occur to remove posted restrictions. A retrofit solution, which is capable of restoring prestress losses and strength reduction in mild to moderately deteriorated prestressed concrete bridge superstructures such that the useful service life of the bridge can be extended for 3 to 5 years allowing a more permanent solution to be planned and budgeted, would be useful. A practical retrofit alternative is one that that can be installed relatively rapidly by DOT maintenance personnel, can immediately restore traffic upon installation, can be easily inspected and maintained as necessary, and should not be more costly than user costs associated with load restrictions or closures. The thesis describes the results of an experimental program to examine the practical and technical feasibility of restoring prestress losses in deteriorated prestressed concrete C-channel beams using a mechanically-fastened fiber-reinforced polymer (MF-FRP) retrofit methodology. This study found that the developed MF-FRP retrofit methodology is capable of restoring the original bridge load rating and can be installed by a single DOT maintenance crew within 1 to 2 days, depending upon the length and level of deterioration of the candidate bridge. Small-scale testing to optimize the mechanical anchor pattern with respect to the capacity of the FRP material was examined and the number of fasteners required for a typical application was determined. A prestressing mechanism for the retrofit and connection design to attach the MF-FRP retrofit system was developed, including effects of the significant spatial restrictions found in the field. The methodology was optimized with respect to FRP efficiency and retrofit installation time. The MFFRP retrofit solution was tested on 6 full-scale prestressed concrete C-channel beams recently removed from service. The full-scale tests examined the behavior of the undamaged (control) and deteriorated beams with and without the MF-FRP retrofit. The results of the full-scale tests indicated that the MF-FRP retrofit solution presented in this study is capable of restoring the original load rating of prestressed concrete C-channel beams with mild to moderate prestress loss due to deterioration, and it is feasible for the MF-FRP retrofit to be rapidly installed on-site on a bridge and immediately restore traffic upon installation. Technical limitations and difficulties with field installation techniques used in the initial design resulted in significant changes in both the design and field-fabrication methods. Basic production rates for the initial and improved designs were determined, confirming that the field installation can be completed in as little as a single work day by a typical 4-worker DOT maintenance crew. Additionally, a limited qualitative cost comparison indicates that the proposed MF-FRP methodology is economically feasible with the break-even point between the initial installation and material cost to the DOT and the vehicle operating cost savings occurring between a few days and a few months, depending upon the traffic volume, detour length, and posted restriction level for a deteriorated bridge

Rapid Restoration of Deteriorated Prestressed Concrete Bridges Using Mechanically Fastened Fiber Reinforced Polymer

This presentation introduces a methodology to rapidly address deteriorated prestressed concrete bridge superstructures using prestressed mechanically-fastened fiberreinforced polymer (MF-FRP). Currently, departments of transportation (DOTs) must post load restrictions or closures on bridges with deteriorated prestressed concrete superstructures that can no longer carry original design loads. These posted restrictions and closures result in detours that increase travel time and vehicle operating costs for detoured vehicles, impacting commerce, public transportation, and emergency services. Often, load restrictions and closures must remain in place for several years to allow for budgeting, design, and contracting cycles prior to scheduling and completion of permanent repairs or superstructure replacement which must occur to remove posted restrictions. Therefore, a methodology which is capable of restoring prestress losses and strength reduction in mild to moderately deteriorated prestressed concrete bridge superstructures such that the useful service life of the bridge can be extended for 3 to 5 years while a permanent solution is planned and budgeted is desired. Further, a retrofit solution that can be installed rapidly by DOT maintenance personnel, can immediately restore traffic upon installation, and can be easily inspected and maintained is necessary for successful implementation into existing DOT policies and procedures

Crack Density and Elastic Properties of Sustainable Concretes

This paper examines relationships between changes in the microstructure and selected elastic properties of various concrete mixtures exposed to moderately elevated temperatures. The crack density parameters before and after exposure were estimated from the shear modulus measured wet and dry of 1 in. thick by 4 in. diameter (25 x 100 mm) disks. Mixtures examined included both granitic and lightweight coarse aggregates in combination with cementitious systems containing either 20% fly ash, 60% fly ash, termed enhanced sustainability, or 60% slag cement. This study found that the changes in crack density parameter resulting from exposure to elevated temperatures appear to be more sensitive to differences between cementitious materials than to differences between aggregate type or cementitious material proportions. A critical finding was that the relationship between initial crack density parameter and changes in crack density parameter were similar regardless of fly ash content

Student Perceptions of the Civil Engineering Body of Knowledge: Comparison of Two Academic Institutions

Student Perceptions of the Civil Engineering Body of Knowledge: Comparison of Two Academic InstitutionsIn 2008, the American Society of Civil Engineers (ASCE) updated their body of knowledge(BOK2) that defines how a combination of education and experience shall fulfill developmentalrequirements for entry into the civil engineering (CE) profession. A student seeking licensure asa professional engineer (PE) ought to attain a specified level of achievement in each of 24different foundational, technical, and professional outcomes in order to demonstrate theproficiency and preparedness the profession expects.Determining how potential and existing civil engineering students perceive the BOK2 has been asubject of interest, recently investigated by Angela Bielefeldt at the University of Colorado,Boulder (CU). Potential students can use the BOK2 to learn about their chosen field of study,visualize a roadmap for future development, and better understand the dedication their professionrequires. Graduating seniors can use the BOK2 to assess their personal development, their ownstrengths and weaknesses, and coincidently identify the strengths and weaknesses of theirundergraduate engineering program. Student feedback can help leaders in higher education tomake positive changes in their school’s program in order to better prepare students forprofessional service.This study replicates Bielefeldt’s 2010 investigation under different conditions (i.e. at a militaryacademy as opposed to a research-oriented academic institution) in order to provide confirmationthat the BOK2 framework is a useful tool for evaluating CE curriculums across a wide range ofinstitutions. We queried 42 seniors within a military academy’s CE program on their personalstrengths and weaknesses in the context of the 24 outcomes suggested by the ASCE BOK2. Inaddition, we asked these students to identify apparent curriculum weaknesses and rank order the24 outcomes in terms of perceived importance.This study is of interest to any undergraduate CE program administrator who is interested inassessing pedagogy and developing learning experiences to better prepare students forprofessional licensure. The study also assists practicing engineers to provide appropriatementorship and engineering experience to further prepare engineer interns for eventual licensureas a PE

Anchor Bolt Patterns for Mechanically Fastened FRP Plates

This paper examines the results of material testing of hybrid carbon and glass fiber-reinforced polymer (FRP) plates for use in prestressed mechanically fastened applications. The small-scale material tests were conducted in three phases: (1) uniaxial tension without holes, (2) uniaxial tension with open holes, and (3) uniaxial tension with single- and multibolt connections. In all three phases of testing, Digital Image Correlation (DIC) was used to obtain continuous strain data, showing holistic strain field development through failure. A total of 89 tests were conducted across 17 treatment groups to develop an anchor pattern and fastener spacing which is optimized with respect to maximum capacity and behavior under anticipated service load conditions. The tests presented comprise the initial phase of a larger project that aims to employ prestressed mechanically fastened FRP (MF-FRP) plates as a retrofit repair solution for deteriorated prestressed concrete bridge superstructures. Results conclude that 2 lines of 11 bolts with diameters of 12.7 mm, with longitudinal spacing of 100 mm and transverse spacing of 38 mm, provide an end-region anchor pattern with an ultimate capacity of 206 kN which is 89% of the ultimate capacity for the examined FRP plate with holes

Prevention myths and HIV risk reduction by active drug users

Drug injectors and crack users (526) in South Florida responded to a survey questionnaire that was designed to examine belief in the effectiveness of various strategies, other than condom use, employed to reduce personal risk of contracting HIV during sexual acts. Each strategy was believed to be effective by at least one quarter of the study participants. Factor analysis was used to group these strategies. Subsequent multivariate analysis indicated that the participants who believed in the effectiveness of HIV prevention strategies other than condom use were also less likely to report using condoms. These findings highlight the need for prevention interventions to elicit prevention myths and the full range of risk reduction strategies practiced

DIC Strain Field Measurement of FRP Plates with and without Holes

This paper examines the results of material testing of hybrid glass/carbon fiber reinforced polymer (FRP) plates for use in mechanically fastened applications. The small-scale material tests were conducted in three phases: 1) uniaxial tension without holes, 2) uniaxial tension with open holes, and 3) uniaxial tension with bolted connections. In all three phases of testing, Digital Image Correlation (DIC) was used to obtain continuous strain data, showing holistic strain field development through failure. The high-resolution strain data provides detailed information for the design of an efficient hole pattern in Mechanically Fastened-Fiber Reinforced Polymer (MFFRP) plates. The tests presented here are an initial phase of a larger project that aims to employ prestressed MFFRP plates as a repair for deteriorated prestressed hollow-core bridge slabs. Candidate slabs are those that have exposed tendons such that the bridges are typically load posted. It is proposed that the use of a prestressed MFFRP repair will restore lost performance until replacement can be scheduled in a way that is cost effective, rapid, and enables periodic inspection over the lifespan of the short-term repair – prior to scheduled superstructure replacement. The use of prestressed MF-FRP in this application will eliminate the need for an adhesive bond and QA/QC concerns that are often associated with externally bonded FRP

Shock to the System: How a Teaching and Learning Model Held up in a Global Pandemic

In the late 1990s, the Department of Civil and Mechanical Engineering at the U.S. Military Academy (West Point) formulated a teaching model which guided the training of new faculty. The model served faculty well as they provided instruction and developed learning activities. The model remained unchanged for about 15 years until a team of faculty conducted a methodical review of the literature, reflected on desired outcomes, and deliberated about the role that this model played in achieving the institution and department’s mission and vision. The result was an updated teaching and learning model which was presented at the ASEE National Convention in 2017. As was emphasized in a previous paper, the faculty believed strongly that the teaching and learning model be viewed as a living document that must be applied and regularly challenged, discussed, and updated to ensure it remained relevant. When the coronavirus pandemic began in early 2020, the institution, which had very limited experience providing online instruction, sent students home, and switched to delivering fully remote courses within less than one week. Like most other academic institutions, this was a significant shock to the teaching and learning environment; faculty rapidly learned new tools and tried new techniques to teach, engage, and interact with students. After the semester ended, the department formed teams of faculty to devote a portion of the summer to gathering lessons learned from the spring term, examining the literature about online education, and providing recommendations for the fall term. These activities led to discussions about how well the existing teaching and learning model applied to the vastly different environment of online versus in-person education. This inspired the faculty to a thorough examination of the living document. During the subsequent fall term, formal faculty discussions about the model were facilitated. Topics from these discussions were grouped as follows: (1) aspects of the model that can be applied unchanged in the online environment, (2) aspects of the model that are difficult or impossible to apply in the online environment, and (3) ideas that need to be included in the model to support the online environment. The discussions included topics unrelated to the online environment, highlighting important aspects of the model that deserve additional consideration. Results from these faculty discussions will inform a team of faculty that will develop an updated version of the model in the summer of 2021. This work in progress paper summarizes the results from the discussions, highlights preliminary conclusions, and describes future work. This will be of interest to any engineering educator interested in developing and using a teaching and learning model as a guidepost for themselves or their department. This will also be of interest to educators desiring a better understanding of the similarities and differences between in-person and remote teachin

Corrosion Mitigation for Mechanically-Fastened Fiber-Reinforced-Polymer Composites

Mechanically-Fastened Fiber Reinforced Polymer Composites (MF-FRPs) are currently being used to extend the useful service life of deteriorated bridges. However, the A325 Steel fastener assemblies used to attach the MF-FRP system to the bridges are experiencing noticeable corrosion. Through electrochemical polarization measurements and Tafel analysis, the expected lifetime of the A325 fastener assembly was determined and compared to other similar materials, Military Specification Grade 5 Steel (MTD-STD) and PH 17-4 Stainless Steel (PH 17-4). ASTM B117 salt fog testing was performed on each material fastener assembly to simulate the corrosion that should be experienced by each material. The electrochemical analysis and the ASTM B117 salt fog test confirmed the MIL-STD assembly corroded at a much slower rate compared to either A325 or PH 17-4. It was determined that the useful life of the fastener assembly could be extended from 6.5 year using A325 to 372 years using MIL-STD. Implementation of this engineering materials solution will extend the useful life of the MF-FRP fastener assembly however, a cost benefit analysis determined that continuing to use A325 is still the best option given the desired useful life of the MF-FRP retrofit system is 3 to 5 years