Rozprawy doktorskie na temat „Mine backfill”
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O'Neill, Mark A. "Creep settlement of opencast mine backfill". Thesis, Sheffield Hallam University, 2007. http://shura.shu.ac.uk/20148/.
Pełny tekst źródłaHan, Fa Sen. "Geotechnical Behaviour of Frozen Mine Backfills". Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20250.
Pełny tekst źródłaZhu, Zheming 1965. "Analysis of mine backfill behaviour and stability". Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84453.
Pełny tekst źródłaIn this thesis, first laboratory tests and in-situ tests are implemented to determine backfill material properties and backfill stress distribution. The laboratory tests include high sulphide paste fill property tests and layered backfill tests. Second, a backfill finite element model is presented and it is validated by the results of laboratory tests and in-situ tests. Finally, by using this model, the following subjects are studied, (1) backfill stress distribution; (2) influences of backfill material properties and dimensions on backfill stability; (3) stress distribution of layered backfill; (4) optimum layered backfill. The results show that: (a) The variation of backfill material properties is quite large, the compressive strength of the layered backfill model is much higher than that of the non-layered backfill model, and the backfill vertical stress is much less than that anticipated by the formula, rhogH; (b) During the process of adjacent pillar recovery, the minor principal stress inside a backfill is tensile, and this tensile principal stress causes backfill failure and spalling near the exposed surfaces. The spalling size progressively increases with the height of the exposed surface, and a sliding zone creates and leads to backfill collapse; (c) Optimum backfill material should be high elastic modulus, high Poisson's ratio and low density. Optimum backfill size should be large depth and small width; (d) For layered backfill, no sliding zone occurs during the process of adjacent pillar recovery, so layered backfill can improve backfill stability. The optimum layered backfill should consist of strong layers distributed evenly with thicknesses of 1~2m and weak layers 2~2.5 times the thickness of the strong layers. This can save binder consumption by about 11%.
Aldhafeeri, Zaid. "Reactivity of Cemented Paste Backfill". Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/38111.
Pełny tekst źródłaBlanchfield, Richard. "Volume change characteristics of opencast coal mine backfill". Thesis, University of Sheffield, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.480898.
Pełny tekst źródłaPiciacchia, Luciano 1959. "Field and laboratory studies of mine backfill design criteria". Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=74360.
Pełny tekst źródłaA backfill classification system is proposed based upon size distribution. A series of design equations are presented which relate to this system. These equations represent the means by which backfill geomechanical behaviour can be related to physical properties. This is considered to be fundamental to an effective backfill design procedure. Derivation of the equations has been based upon analysis of data from a program of laboratory and in situ testing conducted in ten operating Canadian mines by the author, together with other published work.
The in situ testing required the development of a pressuremeter testing procedure novel to underground mining. The theoretical basis for the employment of pressuremeter data has been examined and behavioral equations have been developed to describe the deformation and stress history during a backfill material test. In addition two new equations have been developed for the analysis of pressuremeter data. The in situ data collected has been correlated with laboratory derived geomechanical data for the same backfill materials.
The geomechanical properties associated with the proposed backfill classifications have also been related to their influence on backfill behaviour in three mine backfill roles: free standing stability during pillar recovery in bulk mining methods; dynamic interaction with stope walls in rockburst prone ground; and ability to reduce stresses in highly stressed rock masses. This work has been based on new and established modelling methods and aims to provide insight into the effectiveness of the backfill classes in these roles of growing practical significance.
Bouzaiene, Riadh. "On the flow mechanics of mine backfill slurries in pipelines". Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=28992.
Pełny tekst źródłaThe main contribution of this work is, particularly, in the development of an analytical model to describe the flow and predict the pressure gradient of a class of high density backfill whose motion in pipelines follows the Plug Flow Model (PFM). The development of the model called for investigating the conditions required for establishing Plug Flow. It was found that mix proportioning procedures, similar to those found in the concrete industry, are key factors in obtaining Plug Flow.
Pressure drop was found to be a function of the thickness of the Bingham plastic annular layer surrounding the cylindrical core of aggregates. Analytical equations were proposed to solve for the thickness of this layer by considering the rheology of the mixture. Alternatively, the thickness of the annular layer may be estimated by considering the relative proportions of the mixture with respect to aggregates void content. The model offered pressure drop predictions in good agreement with published data. The proposed model may also serve as an alternative to Mooney's method, when dealing with the annular lubricating layer effect characterising mixtures in Plug Flow.
Fadaei, Kermani Mehrdad. "An investigation into a new binder for hydraulic backfill /". Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=112568.
Pełny tekst źródłaIn order to improve the mechanical behaviour of fill, cementitious materials are used. These cementitious materials are expensive. As a result the consumption of these cementitious materials has to be optimized and minimized in a way that the required strength is met. The objective of this research is to investigate a new type of backfill, which is known as gelfill. Gelfill binders usually consist of alkali activators such as sodium silicate and the other cementitious materials. Sodium silicate has been used in waste treatment and activation of artificial pozzolans such as blast furnace slag and fly ash.
The work presented in this thesis is to evaluate the use of sodium silicate in gelfill. Consequently, the influence of mixing time, mixing sequence and curing time are studied on gelfill and silica sand hydraulic backfill. Various tests including unconfined and confined compressive strength were conducted in order to investigate the mechanical behaviour of samples. By conducting mercury intrusion porosimetery (MIP) and scanning electron microscopy (SEM), microstructure and mineralogical properties of specimens were studied.
The result of this thesis demonstrates that gelfill compared with silica sand hydraulic backfill has better mechanical properties. In addition, other variables, including: mixing time and sequence, have a significant effect on gelfill.
Bowman, Charles H. "Geotechnical charcterization of coal refuse for use as a backfill material". Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-08182009-040343/.
Pełny tekst źródłaVan, Tonder Warren Deon. "Centrifuge modelling of permeability in a heterogeneous coal mine backfill sequence". Diss., University of Pretoria, 2015. http://hdl.handle.net/2263/57291.
Pełny tekst źródłaDissertation (MSc)--University of Pretoria, 2015.
tm2016
Geology
MSc
Unrestricted
Hughes, Paul B. "Performance of paste fill fences at Red Lake Mine". Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/2502.
Pełny tekst źródłaCui, Liang. "Multiphysics Modeling and Simulation of the Behavior of Cemented Tailings Backfill". Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36145.
Pełny tekst źródłaBenton, Donovan. "The Use of Paste Backfill to Increase Long-Term Mine Stability and Coal Extraction: A theoretical study for Illinois Basin room and pillar coal mines". OpenSIUC, 2013. https://opensiuc.lib.siu.edu/theses/1249.
Pełny tekst źródłaGhirian, Alireza. "Coupled Thermo-Hydro-Mechanical-Chemical (THMC) Processes in Cemented Tailings Backfill Structures and Implications for their Engineering Design". Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34605.
Pełny tekst źródłaRask, Amanda. "Indirect methods as quality control of cemented hydraulic fill : Renström mine, Boliden mineral AB". Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-72962.
Pełny tekst źródłaZeni, Marilia Abrão. "Caracterização de backfill cimentado na mina Aguilar". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/143712.
Pełny tekst źródłaAs a consequence of the ongoing reduction of mineral resources and the high cost involved in the construction of a mine, the maximum recovery of a mineral deposit becomes a fundamental issue. Therefore, besides the need of caution on the choice of the mining method, it is possible to make use of additional recovery methods, such as the recovery of pillars. This research was based on the determination of the characterization of the fill (cemented backfill) used in avoid stopes that allows the subsequent recovery of adjacent pillars. The characterization of the fill consists of determining the uniaxial compressive strength of the backfill required for an efficient filling, developing an optimal particle-size distribution for the aggregates and finding the cement-water ratio necessary to reach the desired resistance. The methodology developed to obtain the new characterization is comprised of several steps which include field work and laboratory tests. First, cement dosing parameters and particle size of the aggregates (already used at the filling manufacturing plant), as well as their corresponding strength, were obtained through analyses in the field work. Then, theoretical definitions of the ideal cement dosing and optimal particle-size analysis were carried out based on the uniaxial compressive strength that has been identified as necessary to comply with the geomechanical requests from the rock mass, and then later, the new theoretical characterization was tested by making backfill samples, followed by execution of compression tests. During the first stage of this methodology, it has been identified a high proportion of clay particle size for the aggregates, that have affected the strength results obtained from the characterization used initially. From this point, we decided to build the optimal particle-size curve without this fraction. Uniaxial compressive strength, calculated as 2.69 MPa, was obtained from the long-term planning that determines the full recovery of the existing pillars in the mine. In this way, the entire area to be mined was considered as a single block. Finally, the cement dosing has been identified as 4% by weight, which together with the optimal particle size, is able to achieve the expected strength values. In order to effectively fulfill the mine production planning over the next years of lifespan, the filling should provide the mine local geomechanical stability at open stopes level, with vertical walls of stable backfill, and also global stability at the contacts between levels and access galleries. This will only be achieved if the new characterization is correctly applied.
Reed, S. M. "Groundwater recovery problems associated with opencast mine backfills". Thesis, University of Nottingham, 1986. http://eprints.nottingham.ac.uk/11881/.
Pełny tekst źródłaVissotto, Júnior Lucas Alberto. "Análise tridimensional de mina subterrânea com ênfase na interação entre maciço e preenchimento (caso de estudo: mina Cuiabá)". reponame:Repositório Institucional da UnB, 2013. http://repositorio.unb.br/handle/10482/15754.
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Este trabalho apresenta uma análise tridimensional de mina subterrânea com ênfase na interação entre maciço rochoso e preenchimento (backfill), considerando o comportamento mecânico do maciço enquanto ocorre o progresso das escavações e da disposição com aumento da tensão confinante e endurecimento do módulo de deformabilidade. Foi realizado o monitoramento do caso de estudo da Mina Cuiabá e comparados os resultados com as modelagens tridimensionais. O tipo específico de lavra estudada foi o cut and fill com orientação sub vertical. Nas modelagens foi analisado o processo de endurecimento do modulo de deformabilidade do backfill, de acordo com a etapa do ciclo de lavra. Os resultados do monitoramento e das modelagens mostraram que a adoção pelo backfill contribui de modo ativo para a estabilidade e segurança da mina. O aumento da tensão confinante devido ao endurecimento do backfill aumentou a interação mecânica com o maciço. Um aspecto sócio ambiental importante relaciona-se ao preenchimento das escavações com rejeito que tendem a mitigar os impactos ambientais, principalmente pela considerável redução dos volumes de rejeitos dispostos em superfície. _______________________________________________________________________________________ ABSTRACT
This study presents a numerical and experimental three-dimensional analysis of the interaction rock mass / backfill, considering the mechanic behavior of rock mass, during the process of excavation and backfill disposal, with increase of the confining stress and the module deformability hardening. The study case of Mine Cuiabá was monitored and the results were compared with the three-dimensional models. The specific type of mine studied was the cut and fill with sub vertical orientation. In the simulations was considered the module of backfill deformability that varies according to the stage of the exploration cycle. The disposal via backfill technology was simulated and monitored, which the results showed a positive contribution with the stability and safety of mine. The increase of the confining stress due to the hardening of backfill deformability module improved the interaction rock mass and backfill. This study showed that the backfill disposal linked to underground exploration mine tends to mitigate the environmental impacts in the mine.
Masniyom, Manoon. "Systematic Selection and Application of Backfill in Underground Mines". Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2009. http://nbn-resolving.de/urn:nbn:de:bsz:105-4418234.
Pełny tekst źródłaVicente, Annalisa Sarga. "Assessing different coal combustion residue backfill scenarios in opencast coal mines, Mpumalanga, South Africa". University of Western Cape, 2020. http://hdl.handle.net/11394/7853.
Pełny tekst źródłaCoal-fired power stations produce large volumes of coal combustion residues (CCRs), which are disposed of in hold ponds or landfill sites. These ash storage facilities are limited in space and are approaching the end of their capacities, thus additional land is required for extensions. If new land is not sourced, power plants will be forced to cease operations, resulting in increased expenditure costs and environmental liability. A proposed disposal solution is to backfill opencast coal mines with CCR monoliths. However, there is limited knowledge on the hydraulic behaviour of CCRs in an opencast coal mine environment. This leads to an inability to assess this applications feasibility and determine whether this activity will have a positive, negligible or negative effect on groundwater quality. This study aims to address this gap in knowledge by assessing the flow and transport properties of CCRs under numerous theoretical backfilling conditions.
Nujaim, Mutaz. "Comportement géomécanique des barricades rocheuses et des remblais en pâte cimentés : expérimentations et modélisations". Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0195.
Pełny tekst źródłaPrecious metals (such as gold and silver), and base metals (such as copper and others) are mined from the underground by excavation, creating voids of various sizes called (stope) which are interconnected by galleries or drifts (for circulation and draw point). In the case of cut-and-fill mining, these voids are usually filled with cemented paste backfill (CPB) which is a mixture made of concentrator mill tailings, of a binding agent (e.g., cement) and mixing water. Since the CPB is placed in the liquid state (solid-liquid suspension) in the underground stopes, it is necessary to use a retaining structure to contain it during backfilling. This retaining structure is called a barricade and can be constructed from wood, concrete, bricks, shotcrete or from waste rock available underground and which come from the drift’s development. Barricades built from waste rock are the most common in Quebec and Canada because they are economical, readily available (underground) and promote water drainage during backfilling, which promotes self-weight consolidation of the CPB, and therefore, reduction of pore water pressure. To date, little information exists on the real in situ characteristics of these barricades (such as their grain size distributions, their failure strength, the probable mechanism of their rupture and the standard dimensions used) to support their design in a meaningful way to ensure the safety of workers and mining equipment, which would contribute to the reduction of the mining cycle, and consequently, to the increase of mining productivity. The work of this thesis project was based on physical and numerical modeling to better understand the complex geomechanical behavior of waste rock barricades. A reduced-scale physical model of a mine stope was developed and constructed from translucent plexiglass plates to simulate backfilling in underground mines. A specific methodology was developed for the execution of the tests: instrumentation of the reduced-scale model using pressure sensors (total and pore water), calibration of the sensors, filling of the reduced-scale model with CPB, continuous monitoring of the tests using high-definition cameras. The tests carried out have made it possible to highlight the main probable mechanism of rupture of the waste rock barricades, as well as the estimation of the maximum pressure at the time of their rupture. The effect of waste rock particle size distribution on the stability and integrity of waste rock barricades due to the CPB pressure was also analyzed. Part of the tests carried out on the reduced-scale model were modeled using the Geostudio 2018 numerical code (GeoSlope Intl.) through calibration with the experimental results. The results of the simulations performed reproduced well the general behavior observed during the tests on the reduced-scale model, but with a significant difference in the pressure values. Simplified analytical solutions based on limit equilibrium have also been proposed based on experimental observations for the stability analysis (with respect to sliding and friction) of waste rock barricades. Some recommendations were proposed to take this study further by including the effect of various factors (e.g., the position of the barricade in the drift or draw point, the viscosity, and the shear yield stress of the backfill or its solids mass concentration, the shear parameters of the waste rock barricades, the arching effect, etc.)
Coussy, Samuel. "Stabilisation de rejets miniers pollués à l’arsenic à l’aide de sous-produits cimentaires : étude de l’influence de la cristallochimie sur le risque de mobilisation des polluants". Thesis, Lyon, INSA, 2011. http://www.theses.fr/2011ISAL0077/document.
Pełny tekst źródłaThe objective of this study is to understand the geochemical behaviour of arsenic in cemented paste backfills. This technique consists in transporting the tailings in the mine openings. Two types of backfills are prepared in the laboratory for this study. First, synthetic cemented paste backfills artificially spiked with arsenic are synthesized, using silica in replacement of the tailings. In parallel, other cemented paste backfill specimens are prepared with arsenic-rich tailings. In the two cases, various types of hydraulic binders are tested. Several types of investigations are conducted on the cemented paste backfill specimens. A mineralogical characterization is carried out with the help of specific tools. At the same time, cemented paste backfill samples are submitted to several complementary leaching tests, to assess the mobility/immobilization potential of arsenic in these matrices. Finally, geochemical modeling is implemented, based on the results of the two previous studies, in order to refine the understanding of the nature and stability of the arsenic compounds. The results show that arsenic is better immobilized in Portland cement and slag-based matrices, rather than in fly ash-based matrices. The variable leaching behaviour from a given matrix to another is due to different arsenic trapping mechanisms. Arsenic can precipitate and form several arsenic minerals, mainly calcium arsenates, but also various other secondary compounds, which are different from a matrix to another. Physical entrapment of the tailings grains by the cementitious minerals can also occur, by formation of a coating around the grains, limiting the oxidation and dissolution of arsenic-bearing sulfides (passivation). These mechanisms are involved in the stabilization/solidification of arsenic by cemented paste backfills
Abbasy, Farzaan. "Thermal conductivity of mine backfill". Thesis, 2009. http://spectrum.library.concordia.ca/976499/1/MR63157.pdf.
Pełny tekst źródłaGhazi, Sina. "Modeling of an Underground Mine Backfill Barricade". Thesis, 2011. http://hdl.handle.net/1807/29550.
Pełny tekst źródłaLamos, August Wilhelm. "Controlled loading response cemented backfill support for deep tabular stopes". Thesis, 1993. https://hdl.handle.net/10539/28931.
Pełny tekst źródłaHydraulically placed cemented backfill is increasingly being used as a means of stope support in South African hard-rock mines. The addition of binder provides backfill with a primary compressive strength. the property for which the material has traditionally been utilised. Binder-induced cohesion, however, is not the only factor determining the quality of cemented backfill and the material's utility can be enhanced significantly by applying all of its attributes to the task of stope support. The main purpose of this thesis is, therefore, to examine those factors which influence the performance of cemented backfill, and to provide relevant and useful information for the design of improved cemented backfill mine support for tabular mining excavations. In an extensive laboratory investigation, a number of relevant factors were tested for their influence on the loading behaviour of cemented backfill. Twenty two cemented backfills. grouped according to aggregate type, water content, binder content and binder type, were analysed to determine the influence of composition on their material properties. This study was augmented by several test series on the effects of curing conditions on cemented backfill quality. In a second major investigation, the effects of geometrical parameters, including sample volume and sample width to height ratios were analysed. A further study dealt with the effect of spatially separating sample backfill ribs under normal compression, as well as at high closure rates. It is concluded, that by co-ordinating the composition design of cemented backfills with the spatial configuration of backfill support elements, it is possible to modify all phases of the cemented backfill loading response. This implies the control of the binder-induced compressive strength at low strains, the large-scale yielding behaviour of backfill support, as well as the stiffness of the backfill body at high stresses. In the light of stope support requirements. particularly under rockburst conditions, the capacity of backfill support to yield and absorb rapid stope closure and then to decelerate the hangingwall by the rapid strain-hardening of the, now, large width to height ratio backfill mass, has the potential of substantially increasing mine safety in tabular stopes,
Andrew Chakane 2020
Sargeant, Aubrey Lancelot. "The Application of Post Consumer Glass as a Cementing Agent in Mine Backfill". Thesis, 2008. http://hdl.handle.net/1974/1002.
Pełny tekst źródłaThesis (Master, Mining Engineering) -- Queen's University, 2008-01-29 15:09:30.281
Van, Wyk Wilhelm Jacobus. "Settlement of open cast mine backfill : two large scale field tests". Thesis, 1998. https://hdl.handle.net/10539/26641.
Pełny tekst źródłaThe Electricity Supply Commission of South Africa (Eskom) have identified open cast coal mine backfill areas as potential disposal sites for the large volumes of coal ash produced by their power stations. As Eskom's power stations are mainly situated in agricultural and coal rich areas of the provinces of Mpumalanga and the Free State, the sterilisation of substantial areas of agricultural soil and coal deposits is thus reduced. The construction of a tailings dam or dump on uncompacted open cast mine backfill creates various problems related to the settlement of the backfill. The scale of the operation, the large particle size and heterogeneous nature of the backfill and its method of placement complicates the prediction for settlement of the backfill. Areas in excess of 74 000 ha could be subjected to opencast mining in Mpumalanga and for future development of these areas more information regarding the magnitude and mechanics of mine backfill settlement is required. This dissertation describes two large scale field tests in which the settlement of mine backfiil was studied during the construction of a test section of an ash tailings dam and the construction of a dry ash dump.
Andrew Chakane 2019
Jamali-Firouz-Abadi, Maryam. "Effect of Binder Content and Load History on the One-dimensional Compression of Williams Mine Cemented Paste Backfill". Thesis, 2012. http://hdl.handle.net/1807/35326.
Pełny tekst źródłaChovan, Karen. "An investigation into the use of agglomerated tailings in backfill : a potential tailings disposal option and case study for Eskay Creek Mine, British Columbia". Thesis, 2001. http://hdl.handle.net/2429/11505.
Pełny tekst źródłaDippel, Susan Katherine. "Mineralogical and geochemical characterisation of phosphogypsum waste material and its potential for use as backfill at WMC Fertilizers’ Mine site, Phosphate Hill, N-W Queensland". 2004. http://eprints.jcu.edu.au/103/1/01front.pdf.
Pełny tekst źródłaMasniyom, Manoon [Verfasser]. "Systematic selection and application of backfill in underground mines / vorgelegt von Manoon Masniyom". 2009. http://d-nb.info/994376162/34.
Pełny tekst źródłaAdams, Duncan John. "The determination of the Situ behaviour of backfill nibs in deep level gold mines". Thesis, 2016. http://hdl.handle.net/10539/20794.
Pełny tekst źródłaAdams, Duncan John. "The determination of the in situ behaviour of backfill ribs in deep level gold mines". Thesis, 2016. http://hdl.handle.net/10539/20902.
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