Thesis (M.Eng.)--Memorial University of Newfoundland, 2003. / Bibliography: leaves 93-96.

Thesis (M. Sc.)--University of Hong Kong, 2002.

Digitized by Kansas Correctional Industries

Call number: LD2668 .T4 1959 Y34

published_or_final_version / Civil Engineering / Master / Master of Philosophy

published_or_final_version / abstract / Civil Engineering / Master / Master of Philosophy

Slope stability analyses are commonly performed using computer programs hich perform safety factor calculations using limit equilibrium solutions and search for the critical, or most probable failure surface. These searches are always performed using "direct search" techniques, which are the simplest but least efficient optimization methods. In the future, more advanced optimization algorithms will be incorporated into existing slope stability programs, which will greatly increase the speed with which the search converges to the critical slip surface. The relative efficiency and reliability of these new search strategies must be established by comparative testing on a variety of slope problems. This paper presents a set of problems that will serve as a basis for future comparative testing of different optimization procedures. These problems span the range of slope problems encountered by geotechnical engineers. Baseline measures of efficiency are obtained using an existing slope stability program with grid and pattern search capabilities.

No description available.

No description available.

No âmbito da moderna Mecânica do Contínuo, este texto apresenta um modelo cuja equação objetiva simular fenômenos nos quais a variação da tensão depende da velocidade de deformação. Esta nova equação é fruto de uma modificação introduzida na equação hipoplástica apresentada por Nader, em 1999. Inicialmente é apresentado um apanhado histórico geral, de modo a situar este trabalho no contexto mundial da Ciência Geotécnica. Ao longo do texto, os termos e definições elementares são explicados detalhadamente, de modo que o leitor possa ser bem conduzido para etapas posteriores, que envolvem formulações matemáticas e conceitos mais complexos. A Equação Visco-Hipoplástica é apresentada e seus componentes e comportamentos são analisados. São mostrados resultados de comportamento desta nova equação, não somente para ensaios que envolvem fenômenos viscosos, mas também outros tipos de ensaios, denotando a versatilidade do modelo. Na etapa final, são comparados os resultados de simulação de ensaios de relaxação com os resultados experimentais, obtidos em trabalhos publicados na literatura geotécnica. / In the realm of the modern Continuous Mechanics, this text presents a model whose equation aims at simulating phenomena in which the stress variation depends on the deformity speed. This new equation results from a modification applied to the hypoplastic equation presented by Nader, in 1999. Firstly, the study presents a general historic summary so that this work is situated in the worldly context of Geotechnical Science. Throughout the text, the expressions and elementary definitions are explained in detail so that the reader can clearly understand the following stages, which involve mathematic formulations and more complex concepts. The visco-hypoplastic equation is then presented and its components and behavior are analyzed. Results from the behavior of this new equation are then shown, not only applied to experiments that involve viscous phenomena, but also other kinds of experiments, demonstrating, therefore, the versatility of the model. Finally, the results from the simulation of experiments with relaxation are compared to experimental results, obtained from published studies in the geotechnical literature.