Made available in DSpace on 2014-12-17T15:41:57Z (GMT). No. of bitstreams: 1 JacksonSS_DISSERT.pdf: 3709927 bytes, checksum: 4cec63d3bb80372612d5fdea7750717f (MD5) Previous issue date: 2011-05-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This study aimed to identify and review of the conceptual differences presented by authors of books, focusing on the theme of electronic configuration. It shows the changing concepts of electronic configuration, its implications for the cognitive development of students and their relations with the contemporary world. We identified possible obstacles in books generated in the search for simplifications, situations of different concepts of energy in the electron configuration for sublevels. For this analysis was carried out in several books, and some other general chemistry and inorganic chemistry without distinguishing between level of education, whether secondary or higher. It was found that some books for school books corroborated with higher education, others do not. To check the consistency of what was discussed, it was a survey of 30 teachers, it was found divergent points of responses, particularly with respect to the energy sublevels and authorship of the diagram which facilitated the electron configuration. It was found that the total 22professores, ie, 73,33% answered correctly on the energy sublevel more calcium (Ca) and 80%, ie, 24 teachers responded incorrectly on the iron. As for the authorship of the diagram used to facilitate the electronic configuration, we obtained 93, 33% of teachers indicated that they followed a diagram, and this was called "Diagram of Linus Pauling," teacher 01, 3,33%, indicated that the diagram was authored by Madelung and 01, 3,33%, did not respond to question. Was observed that it is necessary a more detailed assessment of ancient writings, as the search for simplifications and generalizations, not so plausible, lead to errors and consequences negative for understanding the properties of many substances. It was found that quantum mechanics combined with spectroscopic data should be part of a more thorough analysis, especially when it extends situations atoms monoelectronicpolieletr?nicos to describe atoms, because factors such as effective nuclear charge and shielding factor must be taken into consideration, because interactions there is inside an atom, described by a set ofquantum numbers, sometimes not taken into account / Este trabalho teve como objetivo a identifica??o e coment?rio das diferen?as conceituais apresentadas por autores de livros, enfocando o tema configura??o eletr?nica. Essa an?lise mostra as mudan?as de conceitos sobre configura??o eletr?nica, suas implica??es no desenvolvimento cognitivo de alunos e as suas rela??es com o mundo contempor?neo. Identificou-se em livros poss?veis entraves gerados na busca de simplifica??es, situa??es de diferentes conceitos de energia na configura??o eletr?nica por subn?veis. Para tanto foi realizada uma an?lise em v?rios livros, sendo alguns de qu?mica geral e outros de qu?mica inorg?nica sem distin??o entre n?vel de ensino, se m?dio ou superior. Verificou-se que alguns livros de ensino m?dio corroboravam com livros de ensino superior, outros n?o. Para verificar a consist?ncia do que se estava analisado, fez-se uma pesquisa com 30 professores, em que foi encontrado pontos divergentes de respostas, com rela??o principalmente ? energia de subn?veis e autoria do diagrama que facilitava a configura??o eletr?nica. Constatou-se que do total, 22 professores, ou seja, 73,33% responderam corretamente sobre o subn?vel mais energ?tico do c?lcio (Ca) e 80%, ou seja, 24 professores responderam incorretamente sobre o ferro. J? quanto a autoria do diagrama usado para facilitar a configura??o eletr?nica, obteve-se93,33% de professores que indicaram que seguiam um diagrama, e este era denominado de diagrama de Linus Pauling , 01 professor, 3,33%, indicou que o diagrama era de autoria de Madelung e 01, 3,33%, n?o respondeu a pergunta.Foi observado que ? necess?rio uma avalia??o mais minuciosa de escritos antigos, pois a busca de simplifica??es e generaliza??es, n?o t?o plaus?veis, levam a erros e consequ?ncias negativas para a compreens?o das propriedades de muitas subst?ncias. Verificou-se que a mec?nica qu?ntica aliada a dados espectrosc?picos deve fazer parte de uma an?lise mais minuciosa, principalmente quando se estende situa??es de ?tomos monoeletr?nicos para descrever ?tomos polieletr?nicos, pois fatores como carga nuclear efetiva e fator de blindagem devem ser levados em considera??o, devido a intera??es que h? internamente num ?tomo, descrito por um conjunto de n?meros qu?nticos, ?s vezes n?o levados em considera??o

Sublevel caving operations at great depths are subjected both to large stress concentrations that are redistributed as the mining front progresses and to mining-induced seismicity. This is the case for Kiirunavaara mine, Sweden’s largest underground mine. Since the mine was declared seismically active in 2007 / 2008, large rockfalls controlled by structures have happened in many parts of the mine, despite the use of rock support systems designed for bearing dynamic loads. A novel layout for sublevel caving operations, internally named “fork layout” is being tested at a satellite mine. This layout was conceived to place the ore-parallel longitudinal footwall drifts further away from the contact between the orebody and footwall drifts. That way, the differential stresses that generate stress-related damages are expected to be reduced. However, the effect of implementing the fork layout on the hazard potential for structurally controlled rockfalls has not been studied in detail yet. Large rockfalls that occurred in different parts of the mine were analysed with respect to their structures, location of the damage event and type of excavation. The majority of these occurred at footwall drift intersections. Information from damage mapping and seismic events that triggered these rockfalls was used to generate a conceptual model that illustrates the relative spatial relation between the seismic source and damage location. In addition, the seismic source parameters of the events that triggered these rockfalls were processed using scaling laws to obtain ground motion parameters such as peak particle velocity and acceleration at the damage site. The effect of implementing the fork layout on rockfall hazard was tested in the intersections between footwall drifts and crosscuts (FD-CC), and intersections between access and footwall drifts (AD-FD) in two production blocks, using the traditional layout for sublevel caving mining as a point of comparison. Two different fork layouts were tested, FD-CC at 80° (or AD-FD at 100°) and FD-CC at 70° (or AD-FD at 110°). Structural data available from face mapping and oriented core logging was used to define predominant joint sets at the investigated blocks. Using the structural input, wedge volumes at the intersections were modelled deterministically and probabilistically in Unwedge. The variations in wedge volumes formed at the intersections between layouts were used as a proxy for rockfall potential, meaning that if a layout reduced the wedge size, the smaller the rockfall hazard if triggered by a seismic event, and vice versa. It was concluded that most rockfalls at the FD-CC intersections are controlled by structures from three major joint sets. It was observed that rockfalls at FD-CC intersections occurred more often at certain footwall drift orientations. Many seismic events that triggered these rockfalls are located close to the ore passes and generated ground accelerations between 0.5 to 10 times the gravity acceleration. Implementing fork layouts with FD-CC at 80° intersection angle generates larger wedges than the traditional layout and thus, scenarios with a higher rockfall hazard. On the other hand, using fork layouts with FD-CC at 70° intersection angle reduces wedge size at the southern FD-CC intersections; hence, the rockfall hazard is reduced in these intersections. In the northern FD-CC intersections, the wedge volumes are increased and thus, a higher rockfall potential is generated in these intersections. AD-FD at 110° intersection angle generates also a smaller rockfall hazard than the traditional layout in both production blocks.

The sublevel caving mining method is a mass production method with potentially very low operational costs. The success of this method is dependent on, among other factors, the cavability of the orebody and the overlying rock mass. However, caving of the surrounding rock mass also results in deformations in the cap rock as well as on the ground surface above the orebody being mined. From this follows that any existing infrastructure on the ground surface must be relocated as not to be affected by the mining-induced deformations.This thesis work was undertaken to bring about a better understanding of the rock mass behavior in the cap rock of non-daylighting orebodies, with particular application to the Printzsköld orebody as part of the LKAB Malmberget Mine. Rock testing, field observations and underground mapping was conducted to characterize the rock mass in the caving environment. A methodology for identifying the caving front based on seismic monitoring data was derived by studying the Fabian orebody (which has caved to surface), and using laser scanning data for validation. The methodology was then applied to the Printzsköld orebody to identify the caving front.Numerical modeling was performed for various scenarios of the rock mass as mining proceeded. Modeling included (i) stress analysis to understand stress changes and their effects on the rock mass behavior, (ii) discontinuum numerical modeling to quantify the influence of large-scale geological structures on the cave progression, and (iii) discontinuum cave modeling to simulate possible cave mechanisms in the cap rock more explicitly. Laser scanning together with seismic event data were used to calibrate the numerical models.The numerical simulation results showed that as mining progresses, the cap rock and hangingwall were exposed to stress changes that resulted in yielding. Two failure mechanisms were predominantly at play (i) shear failure (dominant in the cap rock) and (ii) tensile failure (dominant in the hangingwall). The presence of the large-scale structures affected thenearfield stresses through slip along the cave boundaries. The effect of the structures on the far field stresses were less significant.Discontinuum modeling to explicitly simulate failure and caving involved simulating the rock mass as a jointed medium using Voronoi tessellations in 2D, and bonded block modeling (BBM) in 3D. Both the 2D and the 3D modeling results showed fair agreement when comparing the inferred boundary of the seismogenic zone, with that identified from seismic monitoring data. Predictive numerical modeling was conducted for future planned mining to assess future cave development in the cap rock. The results from 3D modeling indicated that cave breakthrough for the Printzsköld orebody is expected when mining the 1023 m level, corresponding to approximately year 2022, as per current mining plans. The 2D model was non-conservative with cave breakthrough predicted to occur when mining the 1109 m level, corresponding to the year 2028.The estimated boundary between the seismogenic and yielded zones, as defined in the Duplancic and Brady conceptual model of caving, was coinciding with, or was close to, the cave boundary in the Printzsköld orebody. This may imply that in some areas the yielded zone was not present and that the Duplancic and Brady model may not be universally applicable. Additional work is required to verify this indication, as well as to fine-tune the modeling methodology.

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