| Summary: | Thesis (Ph. D.), Memorial University of Newfoundland, 1999. Engineering and Applied Science Bibliography: p. 306-330 Faceted conical structures have been proposed as an alternative to the true conical form to ease the fabrication and to lower the construction costs. In considering ice forces on these structures, there was a concern with the validity of existing theories. The main objectives of this study are to improve the understanding of the interaction processes and the failure mechanisms of a level ice field against a faceted cone during continuous ice breaking, and to provide engineers with a set of easy-to-apply formulae for ice load calculation. In this thesis, the results of a three-part study, consisting of experimental and theoretical investigations, are documented. In Part I, a pilot series of physical model tests were conducted to provide a clear insight into the interaction processes. Some important interaction features were identified from analysis of the test data which provided a framework vital to further model development. In Part II, the unique rubble piling process was further examined with the aid of existing particulate mechanics and a comprehensive numerical analysis. A new rubble model was developed to predict the geometry of the rubble and the forces exerted on the structure and the base support. In Part III, an appropriate ice breaking model was selected from the existing theories for the adaptation of the new rubble model. The new model, which considers the salient aspects of the rubble piling process, agrees well with the experimental data. -- The above developments and results are significant, because, for the first time, to the knowledge of the author, an ice load model has been established to account for the effect of rubble in ice loading on a multifaceted cone based on essential features of the interaction. The results provide a useful framework for further model development. The state-of-the-art is such that it is now possible to incorporate rubble load in the force calculation with higher degree of confidence. The methodology for doing so has been developed and presented herein, and constitutes the main contribution of this work to the state-of-the-art.
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