DEMIN - Departamento de Engenharia de Minas
URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/510
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3 resultados
Resultados da Pesquisa
Item Estimation of potential failure risks in a mine slope using indicator kriging.(2010) Lana, Milene Sabino; Cabral, Ivo Eyer; Gripp, Adriano Heckert; Gripp, Maria de Fátima AndradeIndicator kriging has been applied to the study of failure mechanisms in a mine slope in Minas Gerais, Brazil, to estimate potential failure risks in limited areas along this slope. Timbopeba Mine, Vale Company, is an open pit iron mine situated in the Quadril´atero Ferr´ıfero, a very important mining district in Minas Gerais. A slope excavated in quartzite with a maximum height of 200m at the time of this study, has presented many failure problems involving the sliding of blocks formed by discontinuities. These blocks are of limited size in comparison to the dimensions of the overall slope. They appear along the entire slope, wherever discontinuity orientations have led to the kinematic feasibility of these blocks. Geostatistics permits the estimation of local failure probability distributions associated to these local failures, which would not be possible with traditional statistical models. The geostatistical method employed in this study, indicator kriging, is quite suitable because it is unnecessary to assume a particular global distribution of the phenomena being modeled. The model was used for locating areas with a great tendency for sliding failure, as it considers the local spatial variability of discontinuity orientations.Item The use of inclined hemisphere projections for analyzing failure mechanisms in discontinuous rocks.(2003) Lana, Milene Sabino; Gripp, Maria de Fátima AndradeThis paper demonstrates the advantages of using inclined stereographic projections in kinematic analysis of rock blocks in discontinuous rock masses. Some examples of limiting cases are presented. The application of inclined projections is illustrated by its use in a mine slope in Brazil. It is clear from the discussion of these examples that inclined hemisphere projections provide better results than horizontal projections. It is also demonstrated that horizontal projections can lead to incorrect results in limiting cases.Item Fluxo de material fragmentado em passagem de minério nas minas subterrâneas: a prática corrente.(2006) Silva, José Margarida da; Gripp, Maria de Fátima AndradeEsse trabalho é parte de pesquisa realizada para preparação de tese de doutorado e apresenta estudo do fluxo por gravidade de material fragmentado em mineração subterrânea. É descrita a prática corrente em minas brasileiras e estrangeiras, enfocando os índices de acidentes, as ações preventivas e corretivas nas operações que utilizam o fluxo por gravidade de minério desmontado em passagens, presentes em diversos métodos de lavra, como na lavra por subníveis, por corte e enchimento e nos métodos que utilizam o abatimento controlado do teto da escavação subterrânea.