Thesis(M.S.)--Auburn University, 2007. / Abstract. Vita. Includes bibliographic references (p.71-82).

Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains xi, 322 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 212-217).

Thesis (M.S.)--University of Wyoming, 2008. / Title from PDF title page (viewed on June 25, 2009). Includes bibliographical references (p. 24-25).

Thesis (M.S.)--Oregon State University, 2005. / Printout. Includes bibliographical references (leaves 141-148). Also available via the World Wide Web.

Thesis (Ph.D.)--University of Nebraska-Lincoln, 2009. / Title from title screen (site viewed January 12, 2010). PDF text: vii, 138 p. : ill. (come col.) maps (some col.) ; 2 Mb. UMI publication number: AAT 3360089. Includes bibliographical references. Also available in microfilm and microfiche formats.

Thesis (Ph. D.)--University of Montana, 2007. / Title from title screen. Description based on contents viewed Oct. 12, 2007. Includes bibliographical references.

Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.

A research report submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science in Engineering. Johannesburg, 2018 / The use of boulders to create habitat heterogeneity is important for aquatic diversity, and being able to predict the stability of a boulder that is placed in a river will aid in sizing the boulder. Identifying ways to increase the stability could save costs associated with over design or replacement due to the boulder washing away. Existing research on incipient motion centres on determining threshold conditions for bed material or protruding elements within a bed surface with relation to, among others: shape of particle, size of particle, relative depth of particle to flow depth, and impact of channel slope. The existing research is limited to bed material that is of a similar size and there is no research on the conditions for incipient motion elements that are relatively large compared to the bed material it is resting on. An idealised flume study was performed to identify trends that several factors have on boulder stability, as well as to verify the results obtained from a pivoting analysis model prediction for a spherical boulder. An additional study was performed to obtain drag coefficients that were suitable for use on spherical boulders that were either embedded into the bed material or simply resting on top of the bed material. The results of the drag experiments were varied; only the results for the non-embedded were suitable to integrate into the model predictions while drag coefficients for the embedded boulders need to be taken from previously published results. The results of the flume study provided good confirmation of the model predictions with the average absolute experimental error being 4%. The trends identified in the flume study show that the most effective method in improving a boulder’s stability is to embed it into the bed material with this being more effective than increasing the size of the boulder. / MT 2018

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