Performance and Assessment of Rehabilitated Steel Culverts

This thesis explores the effects of rehabilitation on the structural performance of corrugated steel culverts. A full-scale laboratory experiment investigated the effects of grouted slip-liners on the performance of two buried circular corrugated steel culverts. One culvert was slip-lined and grouted using low strength grout, while the other was slip-lined and grouted using high strength grout. The performances of the culverts were measured before and after rehabilitation under service loads using single wheel pair loading at 0.45m of cover. Then, the rehabilitated culverts were loaded to their ultimate limit states. Results showed that the low and high strength grouted slip-liners provided strength well beyond requirements, with the low strength specimen failing at a load 2.4 times the fully factored service load, while the high strength specimen did not reach an ultimate limit state before bearing failure of the soil stopped testing. Results also showed that the low strength specimen behaved rigidly under service loads and flexibly under higher loads, while the high strength specimen behaved rigidly under all loads. A second full-scale experiment investigated the effect of a paved invert rehabilitation procedure on the performance of a deteriorated horizontal ellipse culvert. The performance of the culvert before and after rehabilitation was examined under service loads using tandem axle loading at 0.45m of cover. The rehabilitated culvert was then loaded up to its ultimate limit state. The culvert failed due to the formation of a plastic hinge at the West shoulder, while the paved invert cracked at the invert. Results showed that the rehabilitation increased the structural performance of the culvert, increasing the system stiffness and reducing average strains and local bending at critical locations in the culvert under service loads. A sustainability rating tool specifically for the evaluation of deteriorated culvert replacement or rehabilitation projects was also developed. A module for an existing tool, called GoldSET, was created and tested using two case studies, each comparing the replacement of a culvert using a traditional open-cut method with two trenchless rehabilitation techniques. In each case, the analyses showed that the trenchless techniques were the better alternatives in terms of sustainability.

Proving My Competency One Test at a Time: Internationally Educated Nurses and the Canadian English Language Benchmark Assessment for Nurses

Abstract Professional language assessment is a new concept that has great potential to benefit Internationally Educated Professionals and the communities they serve. This thesis reports on a qualitative study that examined the responses of 16 Canadian English Language Benchmark Assessment for Nurses (CELBAN) test-takers on the topic of their perceptions of the CELBAN test-taking experience in Ontario in the winter of 2015. An Ontario organization involved in registering participants distributed an e-mail through their listserv. Thematic analyses of focus group and interview transcripts identified 7 themes from the data. These themes were used to inform conclusions to the following questions: (1) How do IENs characterize their assessment experience? (2) How do IENs describe the testing constructs measured by the CELBAN? (3) What, if any, potential sources of construct irrelevant variance (CIV) do the test-takers describe based on their assessment experience? (4) Do IENs feel that the CELBAN tasks provide a good reflection of the types of communicative tasks required of a nurse? Overall, participants reported positive experiences with the CELBAN as an assessment of their language skills, and noted some instances in which they felt some factors external to the assessment impacted their demonstration of their knowledge and skill. Lastly, some test-takers noted the challenge of completing the CELBAN where the types of communicative nursing tasks included in the assessment differed from nursing tasks typical of an IENs country or origin. The findings are discussed in relation to literature on high-stakes large-scale assessment and IEPs, and a set of recommendations are offered to future CELBAN administration. These recommendations include (1) the provision of a webpage listing all licensure requirements (2) monitoring of CELBAN location and dates in relation to the wider certification timeline for applicants (3) The provision of additional CELBAN preparatory materials (4) Minor changes to the CELBAN administrative protocols. Given that the CELBAN is a relatively new assessment format and its widespread use for high-stakes decisions (a component of nursing certification and licensure), research validating IEN-test-taker responses to construct representation and construct irrelevant variance is critical to our understanding of the role of competency testing for IENs.