15 research outputs found
Case Study on Aggregate Interlock Capacity for the Shear Assessment of Cracked Reinforced-Concrete Bridge Cross Sections
Students’ Perceptions of Doctoral Defense in Relation to Sociodemographic Characteristics
The doctoral defense is considered to have three dimensions: the scholarly dimension, the emotional (affective) dimension, and the cultural dimension. In this work, I explore the link between sociodemographic factors and students’ perception of the doctoral defense to better understand the affective dimension. In particular, I focus on gender, ethnicity, and age at the time of defense, as well as current position and field of study. To address the influence of these aspects on the affective dimension of the doctoral defense, I first reviewed the literature on these sociodemographic aspects as well as the affective dimension of the defense. I then carried out an international survey on doctoral defenses, defense formats, and students’ perceptions and analyzed the 204 completed surveys for this study using quantitative and qualitative methods. The analysis included cross-correlations between students’ perceptions and the studied sociodemographic aspects. The main results of these analyses are that gender affects various aspects of the students’ perception of the doctoral defense and long-term perception, and that female candidates experience more issues with their committee. Ethnicity is important as well, although the participation of non-white respondents in this survey was limited. The influence of age at the defense is limited, and only for the youngest and oldest age groups did I observe some differences in perception. There is no relation between current position and perception of the candidates during the defense. Finally, field of study is correlated for various aspects of student perception, committee issues, and long-term perception. The conclusion of this work is that sociodemographic aspects, and in particular gender, ethnicity, and field of study, influence how doctoral candidates experience their defense
Students’ Perceptions of Doctoral Defense Formats
The doctoral defense is an important step in the doctoral journey and an essential requirement for obtaining a doctoral degree. Past research on the doctoral defense has focused solely on national practices. In this work, I investigate the potential link between the doctoral defense format based on its major and minor elements and the perception of the defense by the student. For this purpose, I first reviewed the different defense formats used internationally to extract the different elements of the doctoral defense, and the literature on students’ perceptions of the doctoral defense. Then, I carried out an international survey which received 297 responses, of which 204 were completed surveys which I used for the analysis in this article. I first analyzed the outcomes of the survey using qualitative and quantitative methods, and then cross-correlated the outcomes of defense format with the outcomes of student perception. From this analysis, I observed that the defense elements that positively impact the student’s perception are: publication of the thesis before the defense, receiving committee feedback before the defense, knowing the recommendations of one or more committee member in advance, having the supervisor present in the audience or as part of the committee, using a dress code, and including a laudatio. The final conclusion of this work is threefold. The first conclusion is that the details of the defense format impact most the students’ perception. The second conclusion is that doctoral students, on average, value the defense as a positive experience. The third conclusion is that the defense format cannot influence two important aspects of how a student perceives the defense: the student’s inner life and experience during the defense, and the behavior of the committee members
Stop Criteria for Flexure for Proof Load Testing of Reinforced Concrete Structures
Existing bridges with large uncertainties can be assessed with a proof load test. In a proof load test, a load representative of the factored live load is applied to the bridge at the critical position. If the bridge can carry this load without distress, the proof load test shows experimentally that the bridge fulfills the requirements of the code. Because large loads are applied during proof load tests, the structure or element that is tested needs to be carefully monitored during the test. The monitored structural responses are interpreted in terms of stop criteria. Existing stop criteria for flexure in reinforced concrete can be extended with theoretical considerations. These proposed stop criteria are then verified with experimental results: reinforced concrete beams failing in flexure and tested in the laboratory, a collapse test on an existing reinforced concrete slab bridge that reached flexural distress, and the pilot proof load tests that were carried out in the Netherlands and in which no distress was observed. The tests in which failure was obtained are used to evaluate the margin of safety provided by the proposed stop criteria. The available pilot proof load tests are analyzed to see if the proposed stop criteria are not overly conservative. The result of this comparison is that the stop criteria are never exceeded. Therefore, the proposed stop criteria can be used for proof load tests for the failure mode of bending moment in reinforced concrete structures.Concrete Structure