Rozprawy doktorskie: „Open pit mining system”

1

Cetin, Necmettin. "Open Pit Truck /shovel Haulage System Simulation". Phd thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605499/index.pdf.

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This thesis is aimed at studying the open pit truck- shovel haulage systems using computer simulation approach. The main goal of the study is to enhance the analysis and comparison of heuristic truck dispatching policies currently available and search for an adaptive rule applicable to open pit mines. For this purpose, a stochastic truck dispatching and production simulation program is developed for a medium size open pit mine consisting of several production faces and a single dump site using GPSS/H software. Eight basic rules are modeled in separate program files. The program considers all components of truck cycle and normal distribution is used to model all these variables. The program asks the user to enter the number of trucks initially assigned to each shovel site. Full-factorial simulation experiments are made to investigate the effects of several factors including the dispatching rules, the number of trucks operating, the number of shovels operating, the variability in truck loading, hauling and return times, the distance between shovels and dump site, and availability of shovel and truck resources. The breakdown of shovel and trucks are modeled using exponential distribution. Three performance measures are selected as truck production, overall shovel utilization and overall truck utilizations. Statistical analysis of the simulation experiments is done using ANOVA method with Minitab software. Regression analysis gives coefficient of determination values, R2, of 56.7 %, 84.1 %, and 79.6 % for the three performance measures, respectively. Also, Tukey&rsquo
s method of mean comparison test is carried out to compare the basic dispatching rules. From the results of statistical analysis, it is concluded that the effects of basic truck dispatching rules on the system performance are not significant. But, the main factors affecting the performances are the number of trucks, the number of shovels, the distance between the shovels and dump site, finally the availability of shovel and truck resources. Also, there are significant interaction effects between these main factors. Finally, an adaptive rule using the standardized utilization of shovels and trucks is developed.

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2

Radlowski, Jacek K. "In-pit crushing and conveying as an alternative to an all truck system in open pit mines". Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/28512.

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The material transport system in an open pit mine significantly affects the capital and operating costs. All truck haulage is the most common and is a reliable and flexible transport system. On the other hand, this system is very expensive and can cost up to 50% of total mining costs. Its cost is continuously increasing due to the inflation of the fuel, tire, and labour expenditures. In-pit crushing and conveying is an alternative transport system which requires a higher initial investment but gives substantial savings in operating costs. An evaluation of the all truck system versus the in-pit crushing and conveying system has been performed by means of a simulation of both transport systems in the same mine model. Results of the simulation and the data obtained from the feasibility studies provided input for an economic comparison of the alternative transport systems. A cash flow analysis showed that the in-pit crushing and conveying system was competitive with the all truck system, giving a payback within four years and resulting in total costs over 30% lower than those of an all truck system. Three computer programs, written by the author, have been used to analyse the mine model: (1) Open Pit Simulation Program - to model a hypothetical mine and simulate its haulage operation over the mine life, (2) Off-Highway Truck Simulation Program - to simulate the truck haulage on average annual routes in terms of the operating time and fuel consumption for the estimation of the truck fleet size and the fuel cost, (3) Cash Flow Analysis Calculation Program - to compare costs of the alternative transport systems over the whole period of a mine life.
Applied Science, Faculty of
Mining Engineering, Keevil Institute of
Graduate

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3

Kolb, William Edward 1960. "MICROCOMPUTER BASED AUTOMATIC TRUCK DISPATCHING - SYSTEM MODELING AND SIMULATION (MINING, SOFTWARE, ALGORITHM, OPEN-PIT)". Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/292092.

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4

May, Meredith Augusta. "Applications of Queuing Theory for Open-Pit Truck/Shovel Haulage Systems". Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/19218.

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Surface mining is the most common mining method worldwide, and open pit mining accounts for more than 60% of all surface output. Haulage costs account for as much as 60% of the total operating cost for these types of mines, so it is desirable to maintain an efficient haulage system. As the size of the haulage fleet being used increases, shovel productivity increases and truck productivity decreases, so an effective fleet size must be chosen that will effectively utilize all pieces of equipment. One method of fleet selection involves the application of queuing theory to the haul cycle. Queuing theory was developed to model systems that provide service for randomly arising demands and predict the behavior of such systems. A queuing system is one in which customers arrive for service, wait for service if it is not immediately available, and move on to the next server or exit the system once they have been serviced. Most mining haul routes consist of four main components: loading, loaded hauling, dumping, and unloaded hauling to return to the loader. These components can be modeled together as servers in one cyclic queuing network, or independently as individual service channels. Data from a large open pit gold mine are analyzed and applied to a multichannel queuing model representative of the loading process of the haul cycle. The outputs of the model are compared against the actual truck data to evaluate the validity of the queuing model developed.
Master of Science

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5

Patterson, Samuel R. "Optimising the operational energy efficiency of an open-pit coal mine system". Thesis, Queensland University of Technology, 2016. https://eprints.qut.edu.au/95087/1/Samuel_Patterson_Thesis.pdf.

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This thesis investigates factors that impact the energy efficiency of a mining operation. An innovative mathematical framework and solution approach are developed to model, solve and analyse an open-pit coal mine. A case study in South East Queensland is investigated to validate the approach and explore the opportunities for using it to aid long, medium and short term decision makers.

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6

Sperling, Tony. "Risk-cost-benefit framework for the design of dewatering systems in open pit mines". Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/31873.

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Control of groundwater plays an important part in operations at many open pit mines. Selection of an efficient and cost effective dewatering program that will improve slope stability of the pit walls is frequently complicated by the complex and somewhat uncertain hydrogeologic environment found at most mine sites. This dissertation describes a risk-cost-benefit (RCB) framework that can be used to identify the most effective dewatering strategy under such conditions, because the stochastic framework explicitly accounts for uncertainty in hydrogeologic and shear strength parameters in the groundwater flow, slope stability and economic analyses. In the framework, the monetary worth of each design alternative is measured in terms of an economic objective function. This function is defined in terms of a discounted stream of benefits, costs and risks over the operational life of the mine. Benefits consist of revenue generated from the sale of mineral concentrate. Costs include normal operating and dewatering expenses. Monetary risks are defined as the economic consequences associated with slope failure of the pit wall, multiplied by the probability of such a failure occurring. Selection of the best design strategy from a specified set of alternatives is achieved by determining the economic objective function for each design and then selecting the alternative that yields the highest value of the objective function. Estimation of the probability of slope failure requires an accurate assessment of the level of uncertainty associated with each input parameter, a forecast of how dewatering efforts are expected to affect pore pressures in the pit wall in light of the uncertain hydrogeologic environment, and an evaluation of the effect that the pore pressure reductions will have on improving stability of the pit wall. Prediction of the pore pressure response to dewatering efforts is achieved with SG-FLOW, a steady state, saturated-unsaturated finite element model of groundwater flow. Slope stability is evaluated with SG-SLOPE, a two dimensional, limit equilibrium stability model based on the versatile Sarma method of stability analysis. To account for input parameter uncertainty, both the groundwater flow stability models are invoked in a conditional Monte-Carlo simulation that is based on a geostatistical description of the level of uncertainty inherent in the available hydrogeological and geotechnical data. Besides documenting the methodology implemented in the framework to conduct the geostatistical groundwater flow and economic analyses of the objective function, this dissertation also presents a sensitivity analysis and a case history study that demonstrate the application of the RCB framework to design problems typically encountered in operating mines. The sensitivity study explores how each set of input parameters, including hydrologic data, shear strength parameters, slope angles of the pit wall and dewatering system specifications impact on the profitability of the mining operation. The study utilized a base case scenario that is based on overburden conditions at Highland Valley Copper; therefore, the conclusions cannot be applied blindly at other sites. However, the framework can be used to formulate site specific conclusions for other large base-metal open pit mines. After the objective function was calculated for the base case, the aforementioned input parameters were systematically perturbed in turn to study how each parameter impacts on profitability of the mine. The sensitivity study showed that in the particular case analyzed changes in the slope angle and dewatering efforts can improve profitability by many millions of dollars. In particular, steep slope angles can be utilized in the early stages of mine development while the pit walls are relatively low, and then flattened as the pit wall height increases and the monetary consequences of slope failure become more pronounced. Furthermore, the sensitivity results indicated that pit dewatering is likely to be effective over a range of hydraulic conductivities from lxlO"8 m/s to lxlO'5 m/s and that accurate estimation of the mean hydraulic conductivity is much more important than estimating other statistics that describe the hydraulic conductivity field, including the variance and the range of correlation. Results of the sensitivity study clearly demonstrate that the RCB framework can be used effectively to identify the most effective dewatering strategy given a limited amount of geologic and hydrologic information. Also, it is shown that the framework can be used to identify the most important input parameters for each specific dewatering problem and to establish the approximate monetary worth of data collection. The case history study documents how the RCB framework was applied at Highland Valley Copper (HVC). Groundwater control is recognized as an important component of mining operations at this mine site; dewatering measures utilized on the property involve both high capacity dewatering wells and horizontal drains. The benefits of pit dewatering include improved slope stability, drier operating conditions in the pit, and a convenient production water supply. These benefits do not come cheaply, HVC is expecting to spend in excess of six million dollars on groundwater control in the next ten years. Before investing such large sums in groundwater control, mine management should be confident that the capital investment is justified, i.e. that the resulting economic benefits will significantly exceed the costs of the dewatering effort. Using historical data provided by HVC, the case history study documented in this dissertation shows how the RCB framework is used to identify the most profitable combination of slope geometry and groundwater control in design sector R3 of HVC's Valley Pit. By considering three possible slope angle and groundwater control options it is shown that by continuing to implement an aggressive dewatering program, HVC can expect to reduce operating costs by as much as nine million dollars in this design sector.
Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
Graduate

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7

Vasquez, Coronado Pedro Pablo. "Optimization of the Haulage Cycle Model for Open Pit Mining Using a Discrete-Event Simulator and a Context-Based Alert System". Thesis, The University of Arizona, 2014. http://hdl.handle.net/10150/321594.

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The loading cycle in an Open Pit mine is a critical stage in the production process that needs to be controlled in detail for performance optimization. A comprehensive Alert System designed to notify supervisors of cycle times that are below the required performance standards is proposed. The system gives an alert message when one or several trucks are idle or the time of completing production tasks are over a predefined value. This alert is identified by the system and compared with pre-established Key Performance Indicators (KPIs) in order to determine corrective actions. The goal is to determine the strategies that help the production supervisor to optimize the haulage cycle model. A discrete-event simulator has been built in order to analyze different scenarios for route design and queue analysis. A methodology that utilizes different algorithms has been developed in order to identify the least productive times of the fleet. These results are displayed every time the simulation has finished. This research focuses on the optimization of haulage. However, the system is intended for implementation in subsequent stages of the production process, and the resulting improvement could impact mine planning and management as well. Topographic and drilling exploration data from a mine located hypothetically in the state of Arizona, were used to build a block model and to design an open pit; an Arena-based simulation was used to generate operating cycles that represent actual operations (As-Is model). Once the Alert System is implemented, adjustments were applied, and a new simulation was performed taking into consideration these adjustments (To-Be model), including comparative analysis and statistical results.

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8

Hunter, Graham C. "Economic assessment of open pit blasting". Thesis, University of Nottingham, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292230.

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9

Esfahanian, Ehsan. "Hybrid electric haulage trucks for open pit mining". Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/48493.

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Hybrid Electric Vehicles (HEVs) improve fuel economy by taking advantage of the peak efficiency operating envelope of the Internal Combustion Engine (ICE), together with an energy storage system to supply drive power when the ICE has lower efficiency. They also attempt to minimize engine idling. To achieve this improvement, a hybrid design requires an ICE, a generator/motor, motor controllers, and an electric energy storage system (battery or ultra-capacitor) which are connected together in various ways such as Series, Parallel, and Series-Parallel configurations. Multiple strategies have been developed to manage energy use by hybrid electric vehicles in which decisions are made based on input variables such as battery state of charge, driver torque demand, vehicle speed, and transmission gear. For example, as the state of charge of the battery decreases, it becomes more costly to use electricity, and so, the control system tends to transition the power source from battery to fuel. Although diesel-electric mine haulage trucks are in use today, energy storage is not a feature of these systems. Such trucks are typically arranged in a Series configuration in which the engine is completely decoupled from the wheels and used to provide electric energy through a generator to power electric motors on each wheel. The lack of a battery pack is a lost opportunity to improve fuel economy through regenerative braking and/or engine-off operation. This thesis discusses the fuel economy question with respect to road topography and distance data, conditions that can be predicted for mine haulage with relative ease. Access to such data in real-time can be put to advantage to maximize fuel economy on a given cycle. This thesis finds the HEV system can provide fuel savings due to 1) elevation change and 2) engine Brake Specific Fuel Consumption (BSFC) optimization on the order of 22 per cent on a typical open pit mine, which for a haul truck can provide substantial cash flow returns in addition to paying off for the extra capital cost of the hybrid electric system.
Applied Science, Faculty of
Mining Engineering, Keevil Institute of
Graduate

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10

Bastos, Guilherme Sousa. "Methods for truck dispatching in open-pit mining". Instituto Tecnológico de Aeronáutica, 2010. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=1098.

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Material transportation is one of the most important aspects of open-pit mine operations. The problem usually involves a truck dispatching system in which decisions on truck assignments and destinations are taken in real-time. Due to its significance, several decision systems for this problem have been developed in the last few years, improving productivity and reducing operating costs. As in many other real-world applications, the assessment and correct modeling of uncertainty is a crucial requirement as the unpredictability originated from equipment faults, weather conditions, and human mistakes, can often result in truck queues or idle shovels. However, uncertainty is not considered in most commercial dispatching systems. In this thesis, we introduce novel truck dispatching systems as a starting point to modify the current practices with a statistically principled decision making methodology. First, we present a stochastic method using Time-Dependent Markov Decision Process (TiMDP) applied to the truck dispatching problem. In the TiMDP model, travel times are represented as probabilistic density functions (pdfs), time-windows can be inserted for paths availability, and time-dependent utility can be used as a priority parameter. In order to minimize the well-known curse of dimensionality issue, to which multi-agent problems are subject when considering discrete state modelings, the system is modeled based on the introduced single-dependent-agents. Based also on the single-dependent-agents concept, we introduce the Genetic TiMDP (G-TiMDP) method applied to the truck dispatching problem. This method is a hybridization of the TiMDP model and of a Genetic Algorithm (GA), which is also used to solve the truck dispatching problem. Finally, in order to evaluate and compare the results of the introduced methods, we execute Monte Carlo simulations in a example heterogeneous mine composed by 15 trucks, 3 shovels, and 1 crusher. The uncertain aspect of the problem is represented by the path selection through crusher and shovels, which is executed by the truck driver, being independent of the dispatching system. The results are compared to classical dispatching approaches (Greedy Heuristic and Minimization of Truck Cycle Times - MTCT) using Student's T-test, proving the efficiency of the introduced truck dispatching methods.

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11

Albor, Consuegra Francisco. "Exploring stochastic optimization in open pit mine design". Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=92379.

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Over recent years, new methods have been developed to integrate uncertainty into the optimization of life-of-mine (LOM) production planning. This thesis makes use of two stochastic optimization methods: simulated annealing (SA) and stochastic integer programming (SIP); which are implemented in the context of the requirements of mining applications through the use of stochastic simulation to model uncertainty. For the case of SA, the second chapter of the thesis documents the case of a copper deposit where ten simulated realizations are sufficient to provide stable LOM optimization results. In addition, the study shows that the selected true optimal pit limits are larger than the ones derived through conventional optimization. Stochastically optimized pit limits are found to be about 17% larger, in terms of total tonnage, than the conventional (deterministic) optimal pit limits. The difference adds one year of mining and approximately 10% of additional net present value (NPV) when compared to the NPV of conventional optimal pit limits and a production schedule generated stochastically with the same SA algorithm. In the third chapter of the thesis, the SIP based optimizer is used with the purpose of integrating uncertainty into the process of pushback design. Results show the sensitivity of the NPV to the design of starting and intermediate pushbacks, as well as the pushback design at the bottom of the pit. The new approach yielded an increment of ~30% in the NPV when compared to the conventional approach. The differences reported are due to the different scheduling patterns, the waste mining rate and an extension of the pit limits which yielded an extra ~5.5 thousand tonnes of metal.
Depuis quelques années, de nouvelles méthodes ont été développées pour intégrer l'incertitude dans l'optimisation de la planification de la production de la vie-de-mine i.e. life-of-mine (LOM). Cette thèse se sert de deux méthodes d'optimisation stochastique : recuit simulé (RS) et programmation en nombres entiers stochastique (SIP); les deux méthodes sont programmées dans le cadre des besoins des applications d'exploitation de la simulation stochastique et modélisation d'incertitude. Pour le cas de RS, le deuxième chapitre de la thèse décris le cas d'un dépôt de cuivre où dix réalisations simulées sont suffisantes pour fournir des résultats stables d'optimisation de LOM. En outre, l'étude prouve que les véritables limites optimales choisies de mine sont plus grandes que celles dérivées par l'optimisation conventionnelle. Des limites stochastiquement optimisées de mine s'avèrent environ 17% plus grandes, en termes de tonnage total, que les limites optimales (déterministes) conventionnelles de mine. La différence ajoute un an d'exploitation et approximativement 10% de valeur nette additionnel (NPV) une fois comparée au NPV des limites optimales conventionnelles de mine et une cédule de production produit stochastiquement avec le même algorithme de RS. Dans le troisième chapitre de la thèse, l'optimiseur basé sur SIP est utilisé en vue d'intégration de l'inceritude dans le processus de la conception de fosses emboîtées. Les résultats montrent la sensibilité du NPV à la conception de fosses emboîtées de commencement et intermédiaires aussi bien que la conception de la fosse emboîtée du fond de la mine. La nouvelle approche a produit une augmentation de ~30% dans le NPV une fois comparée à l'approche conventionnelle. Les différences rapportées sont dues aux différents cédules de production, du taux de décapage du stérile et d'une extension des limites de la mine qui ont produit ~5.5 mille tonnes supplémentaires

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12

Amankwah, Henry. "Mathematical Optimization Models and Methods for Open-Pit Mining". Doctoral thesis, Linköpings universitet, Optimeringslära, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-70844.

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Open-pit mining is an operation in which blocks from the ground are dug to extract the ore contained in them, and in this process a deeper and deeper pit is formed until the mining operation ends. Mining is often a highly complex industrial operation, with respect to both technological and planning aspects. The latter may involve decisions about which ore to mine and in which order. Furthermore, mining operations are typically capital intensive and long-term, and subject to uncertainties regarding ore grades, future mining costs, and the market prices of the precious metals contained in the ore. Today, most of the high-grade or low-cost ore deposits have already been depleted, and to obtain sufficient profitability in mining operations it is therefore today often a necessity to achieve operational efficiency with respect to both technological and planning issues. In this thesis, we study the open-pit design problem, the open-pit mining scheduling problem, and the open-pit design problem with geological and price uncertainty. These problems give rise to (mixed) discrete optimization models that in real-life settings are large scale and computationally challenging. The open-pit design problem is to find an optimal ultimate contour of the pit, given estimates of ore grades, that are typically obtained from samples in drill holes, estimates of costs for mining and processing ore, and physical constraints on mining precedence and maximal pit slope. As is well known, this problem can be solved as a maximum flow problem in a special network. In a first paper, we show that two well known parametric procedures for finding a sequence of intermediate contours leading to an ultimate one, can be interpreted as Lagrangian dual approaches to certain side-constrained design models. In a second paper, we give an alternative derivation of the maximum flow problem of the design problem. We also study the combined open-pit design and mining scheduling problem, which is the problem of simultaneously finding an ultimate pit contour and the sequence in which the parts of the orebody shall be removed, subject to mining capacity restrictions. The goal is to maximize the discounted net profit during the life-time of the mine. We show in a third paper that the combined problem can also be formulated as a maximum flow problem, if the mining capacity restrictions are relaxed; in this case the network however needs to be time-expanded. In a fourth paper, we provide some suggestions for Lagrangian dual heuristic and time aggregation approaches for the open-pit scheduling problem. Finally, we study the open-pit design problem under uncertainty, which is taken into account by using the concept of conditional value-atrisk. This concept enables us to incorporate a variety of possible uncertainties, especially regarding grades, costs and prices, in the planning process. In real-life situations, the resulting models would however become very computationally challenging.

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13

Meagher, Conor John. "On the directed cut polyhedra and open pit mining". Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=96733.

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Many aspects of open pit mine planning can be modelled as a combinatorial optimization problem. This thesis reviews some existing mine scheduling methods and some of their short comings. Many of the problems are related to the partially ordered knapsack problem with multiple knapsack constraints. This is a special case of a maximum directed cut problem with multiple knapsack constraints on the arcs in the cut.The major contribution of this thesis is the study of the directed cut polytopeand cone, which are the convex hull and positive hull of all directed cut vectors ofa complete directed graph, respectively. Many results are presented on the polyhedralstructure of these polyhedra. A relation between the directed cut polyhedraand undirected cut polyhedra is established that provides families of facet defininginequalities for the directed cut polyhedra from the undirected cut polyhedra.A polynomial time algorithm for optimizing over the undirected cut polytope isgiven for the special case of when an objective function has the same optimal valueon two relaxations, the rooted metric polytope and the metric polytope. Projectionsof the directed cut polytope onto the arc set of an arbitrary directed graph are researched.A method known as triangular elimination is extended from the undirectedcut context to a directed cut context. A complexity result proving that the problem of selecting a physically connected maximum value set of blocks from a 2D grid is NP-hard is given. In the mining literature such a grid would be called a bench.An implementation of a LP rounding algorithm known as pipage rounding isapplied to a pushback design problem. This simple and efficient technique producesresults within 6.4% of optimal for a real data set.
De nombreux aspects de la planification d'une mine à ciel ouvert peuvent être modélisés comme des problèmes d'optimisation combinatoire. La première partie de cette thèse passe en revue quelques méthodes de planification existantes dans la littérature et certaines de leurs lacunes. Plusieurs problèmes sont liés au "partially ordered knapsack (POK)" problème avec contraintes de type sac à dos. Il s'agit d'un cas particulier du problème de coupe maximale dans un graphe dirigé avec des contraintes de type sac-à-dos sur les arcs de la coupe.La contribution majeure de cette thèse est l'étude du cône et du polytope des coupes dirigées, lesquels sont respectivement l'enveloppe convexe et l'enveloppepositive de toutes les coupes d'un graphe dirigé complet.Plusieurs résultats sur la structure polyèdrale des ces polyèdres sont présentés.Une relation entre les polyèdres de coupes dirigées et les polyèdres de coupes non-dirigées est établie. Cette relation permet d'obtenir des familles de facettes définissant des inégalités valides pour les polyèdres de coupes dirigées à partir desinégalités valides et des facettes du polyèdre de coupes non-dirigées.Un algorithme polynomial pour le polytope des coupes non-dirigées est proposé dans le cas particulier d'une fonction objectif ayant la même valeur optimalepour deux relaxations, le polytope métrique enraciné et le polytope métrique. Les projections du polytope de coupes dirigées sur les arcs d'un graphe dirigé sont également étudiées. Une méthode de projection intitulée "élimination triangulaire" est généralisée du cas non-dirigé au cas dirigé.Le problème qui consiste à sélectionner d'une grille 2D un ensemble de sommets connectés de valeur maximale est également étudié. Dans le contexte des mines, les sommets sont les blocs et la grille 2D est un banc. Un résultat de complexité établissant la NP-complétude de ce problème est présenté. Un algorithme "pipage rounding" qui arrondit la solution de la relaxation linéaire a été implémenté pour résoudre le problème de conception de "pushbacks". Cet algorithme simple et efficace a été testé sur des données réelles et a permis d'obtenir des solutions très proches de la solution optimale (écart de 6.4% par rapport à des données réelles).

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14

Mamurekli, Deniz. "Blast-induced ground vibration modelling in open-pit mines". Thesis, University of Nottingham, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357797.

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15

Llana-Rodriguez, A. H. "Orebody modelling and open pit optimization using exploration data". Thesis, University of Nottingham, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355441.

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16

Dunstan, Steven Paul. "Octree solid modelling applications in geology and open pit design". Thesis, Imperial College London, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296412.

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17

Zhao, Yixian. "Algorithms for optimum design and planning of open-pit mines". Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185842.

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A graph theory oriented algorithm for optimal ultimate pit limit design is developed. Mathematical proofs of optimality and convergence are given. The algorithm works on a 3-D block mine model and formulates the model into a directed graph consisting many trees. The vertices in the graph are identified with the blocks in the model and the imposed arcs in the graph represent pit slope constraints. The formation of each directed tree is based more on the ore-waste support concept than geometric constraints alone. The algorithm efficiently handles the joint support and re-allocation problems. The theoretical proof shows that the new algorithm is consistently faster than the well known Lerchs-Grossmann's (LG) algorithm, which is the only algorithm developed in the past one-quarter century capable of producing a true optimum pit limit. The case study results show that the new algorithm is able to generate the optimal ultimate pit limit for a model with 80 columns x 80 rows x 40 levels on an IBM PC AT 80286 microcomputer in 115 minutes. The indirect comparison was made between the results of the new algorithm and the results obtained by P. Huttagosol (1988, 1989) using the LG algorithm. P. Huttagosol optimized a smaller mine model than the one optimized by the new algorithm in 535 minutes of VAX8600 CPU time. The comparison between 535 minutes of VAX8600 CPU time for a smaller model with 115 minutes PC AT processing time for a bigger model clearly indicates that the new algorithm is significantly faster than the LG algorithm. This study also investigates both proposed mathematical optimization approaches and the popular trial and error "pushback" approach to long range mine planning. Both the theoretical analysis and numerical examples demonstrate it is impossible to obtain the optimal solution to mine production scheduling by the approach combining the Lagrangian relaxation with the ultimate pit limit algorithm. The non-convergence due to redundant optimal solutions and the non-convergence due to the requirement of advanced stripping are identified with the proposed approach. The investigation clarifies the long-time misunderstood concept and proves the impossibility of such a research direction itself. Finally, some problem solving techniques which play important roles in the computerized mine planning and grade control are developed and discussed. Specifically, they are: (1) point-in-polygon algorithm, (2) polygon area algorithm, (3) polygon clipping algorithm, (4) blast hole data collection, validation and database maintenance, and (5) the interactive graphics ore-waste delineation.

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18

Mousavi, Nogholi Amin Alah. "Optimisation of open pit mine block sequencing". Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/86697/1/Amin%20Alah_Mousavi%20Nogholi_Thesis.pdf.

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This study presents a comprehensive mathematical model for open pit mine block sequencing problem which considers technical aspects of real-life mine operations. As the open pit block sequencing problem is an NP-hard, state-of-the-art heuristics algorithms, including constructive heuristic, local search, simulated annealing, and tabu search are developed and coded using MATLAB programming language. Computational experiments show that the proposed algorithms are satisfactory to solve industrial-scale instances. Numerical investigation and sensitivity analysis based on real-world data are also conducted to provide insightful and quantitative recommendations for mine schedulers and planners.

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19

Hardy, Raymond J. "Selection criteria for loading and hauling equipment - open pit mining applications". Thesis, Curtin University, 2007. http://hdl.handle.net/20.500.11937/1812.

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Methods for estimating productivity and costs, and dependent equipment selection process, have needed to be increasingly reliable. Estimated productivity and costs must be as accurate as possible in reflecting actual productivity and costs experienced by mining operations to accommodate the long-term trend for diminishing commodity prices, For loading and hauling equipment operating in open pit mines, some of the interrelated estimating criteria have been investigated for better understanding; and, consequently, more reliable estimates of production and costs, also more effective equipment selection process. Analysis recognizes many of the interrelated criteria as random variables that can most effectively be reviewed, analyzed and compared in terms of statistical mathematical parameters. Emphasized throughout is the need for management of the cyclical loading and hauling system using conventional shovels/excavators/loaders and mining trucks to sustain an acceptable “rhythm” for best practice productivity and most-competitive unit-production costs. Outcomes of the research include an understanding that variability of attributes needs to be contained within acceptable limits. Attributes investigated include truck payloads, bucket loads, loader cycle time, truck loading time and truck cycle time. Selection of “ultra-class” mining trucks (≥ 290 -tonne payload) and suitable loading equipment is for specialist mining applications only. Where local operating environment and cost factors favourably supplement diminishing cost-benefits of truck scale, ultra-class trucks may be justified. Bigger is not always better – only where bigger can be shown to be better by reasons in addition to the modest cost benefits of ultra-class equipment. Truck over-loading may, to a moderate degree, increase productivity, but only at increased unit cost.From a unit-cost perspective it is better to under-load than overload mining trucks. Where unit production cost is more important than absolute productivity, under-trucking is favoured compared with over-trucking loading equipment. Bunching of mining trucks manifests as a queuing effect – a loss of effective truck hours. To offset the queuing effect, required productivity needs to be adjusted to anticipate “bunching inefficiency”. The “basic number of trucks” delivered by deterministic estimating must provide for bunching inefficiency before application of simulation applications or stochastic analysis is used to determine the necessary number of trucks in the fleet. In difficult digging conditions it is more important to retain truck operating rhythm than to focus on achieving target payload by indiscriminately adding loader passes. Where trucks are waiting to load, operational tempo should be restored by sacrificing one or more passes. Trucks should preferably be loaded by not more than the nominal (modal) number plus one pass. The research has: • Identified and investigated attributes that affect the dispersion of truck payloads, bucket loads, bucket-cycle time, loading time and truck-cycle time. • The outcomes of the research indicate a need to correlate drilling and blasting quality control and truck payload dispersion. Further research can be expected to determine the interrelationship between accuracy of drilling and blasting attributes including accuracy of hole location and direction. • Preliminary investigations indicate a relationship between drill-and-blast attributes through blasting quality control to bucket design, dimensions and shape; also discharge characteristics that affect bucket cycle time that needs further research.

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20

Hardy, Raymond J. "Selection criteria for loading and hauling equipment - open pit mining applications". Curtin University of Technology, Western Australian School of Mines, 2007. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=118304.

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Methods for estimating productivity and costs, and dependent equipment selection process, have needed to be increasingly reliable. Estimated productivity and costs must be as accurate as possible in reflecting actual productivity and costs experienced by mining operations to accommodate the long-term trend for diminishing commodity prices, For loading and hauling equipment operating in open pit mines, some of the interrelated estimating criteria have been investigated for better understanding; and, consequently, more reliable estimates of production and costs, also more effective equipment selection process. Analysis recognizes many of the interrelated criteria as random variables that can most effectively be reviewed, analyzed and compared in terms of statistical mathematical parameters. Emphasized throughout is the need for management of the cyclical loading and hauling system using conventional shovels/excavators/loaders and mining trucks to sustain an acceptable “rhythm” for best practice productivity and most-competitive unit-production costs. Outcomes of the research include an understanding that variability of attributes needs to be contained within acceptable limits. Attributes investigated include truck payloads, bucket loads, loader cycle time, truck loading time and truck cycle time. Selection of “ultra-class” mining trucks (≥ 290 -tonne payload) and suitable loading equipment is for specialist mining applications only. Where local operating environment and cost factors favourably supplement diminishing cost-benefits of truck scale, ultra-class trucks may be justified. Bigger is not always better – only where bigger can be shown to be better by reasons in addition to the modest cost benefits of ultra-class equipment. Truck over-loading may, to a moderate degree, increase productivity, but only at increased unit cost.
From a unit-cost perspective it is better to under-load than overload mining trucks. Where unit production cost is more important than absolute productivity, under-trucking is favoured compared with over-trucking loading equipment. Bunching of mining trucks manifests as a queuing effect – a loss of effective truck hours. To offset the queuing effect, required productivity needs to be adjusted to anticipate “bunching inefficiency”. The “basic number of trucks” delivered by deterministic estimating must provide for bunching inefficiency before application of simulation applications or stochastic analysis is used to determine the necessary number of trucks in the fleet. In difficult digging conditions it is more important to retain truck operating rhythm than to focus on achieving target payload by indiscriminately adding loader passes. Where trucks are waiting to load, operational tempo should be restored by sacrificing one or more passes. Trucks should preferably be loaded by not more than the nominal (modal) number plus one pass. The research has: • Identified and investigated attributes that affect the dispersion of truck payloads, bucket loads, bucket-cycle time, loading time and truck-cycle time. • The outcomes of the research indicate a need to correlate drilling and blasting quality control and truck payload dispersion. Further research can be expected to determine the interrelationship between accuracy of drilling and blasting attributes including accuracy of hole location and direction. • Preliminary investigations indicate a relationship between drill-and-blast attributes through blasting quality control to bucket design, dimensions and shape; also discharge characteristics that affect bucket cycle time that needs further research.

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21

Maran, Juliano. "Study of truck allocation and truck dispatching problems in open pit mines". Thesis, Virginia Tech, 1987. http://hdl.handle.net/10919/45807.

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In recent years, fierce competition, rising production costs and depressed prices for mineral products, have forced mining companies to find ways to improve efficiency and lower production costs. Given the fact that loading and hauling operations account for up to 60 % of the total costs in surface mining, the optimization and control of these operations can provide substantial reductions in the costs.

Assignment of truck to shovels has been traditionally performed by fixed truck allocation and by truck dispatching. Several operations research and simulation techniques, which can be used to solve problems concerning surface mining operations, are discussed. The types of problems addressed are: how to allocate trucks to loading equipment, how to evaluate the performance of an existing operation, and how to predict the performance of a future system.

For truck allocation, operations research methods such as: dynamic programming, integer programming, and heuristic algorithms are discussed. These methods are used mainly for decision making purposes. Queuing theory techniques, also analyzed, are used mainly for evaluation purposes.

Master of Science

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22

Farrelly, Christopher Terence. "Risk quantificaiton in ore reserve estimation and open pit mine planning /". St. Lucia, Qld, 2002. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16453.pdf.

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Lin, Wei. "Production Scheduling of an Open-pit Mining Complex with Waste Dump Constraints". Thesis, Curtin University, 2021. http://hdl.handle.net/20.500.11937/88095.

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The research work aims to solve the production scheduling problem for open pit mining complexes. It establishes a Mixed-Integer Programming (MIP) model that maximises the net present value of future cash flows and satisfies reserve, production capacity, mining block precedence, waste disposal, stockpiling, and pit sequence constraints. The model is validated and implemented with real-world case.

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24

Soeller, Christopher Philip. "Investigation of the Hydromechanical Effects of Lithostatic Unloading in Open-pit Mines". Thesis, Boston College, 2016. http://hdl.handle.net/2345/bc-ir:107281.

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Thesis advisor: Alan Kafka
The stability of open-pit mine walls and other geotechnical infrastructure is a function of geometry, material properties and groundwater conditions (pore pressure distribution). A portion of failures are attributed to the effect of pore water pressures within the mine wall slopes. The objective of this research was to investigate the interaction between the increments/decrements of stresses that occur during the lithostatic unloading/excavation of the pit and the increments/decrements of pore water pressures. This interaction can be described by the theory of linear poroelasticity, which incorporates the coupling between changes in fluid pressure and changes in stress in porous media. The results of this thesis are displayed in the form of contour charts and graphs
Thesis (MS) — Boston College, 2016
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Earth and Environmental Sciences

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25

Chung, Joyce Sze Yee. "A Mixed Integer Programming Approach for Transitioning from Open-pit to Underground Mining". Thesis, Curtin University, 2020. http://hdl.handle.net/20.500.11937/84566.

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This thesis contributes the mathematical models to solve the transition problem that derives the optimal production scheduling strategy for open-pit and underground mining simultaneously. A new hierarchical clustering algorithm is also presented to manage the large-scale instances of the problem. The implementations at hypothetical and realistic data sets confirm the value of proposed models.

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26

Tipe, Luis Alberto Martinez. "Strategic project evaluation for open pit mining ventures using real options and allied econometric techniques". Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/48334/1/Luis_Martinez_Thesis.pdf.

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Open pit mine operations are complex businesses that demand a constant assessment of risk. This is because the value of a mine project is typically influenced by many underlying economic and physical uncertainties, such as metal prices, metal grades, costs, schedules, quantities, and environmental issues, among others, which are not known with much certainty at the beginning of the project. Hence, mining projects present a considerable challenge to those involved in associated investment decisions, such as the owners of the mine and other stakeholders. In general terms, when an option exists to acquire a new or operating mining project, , the owners and stock holders of the mine project need to know the value of the mining project, which is the fundamental criterion for making final decisions about going ahead with the venture capital. However, obtaining the mine project’s value is not an easy task. The reason for this is that sophisticated valuation and mine optimisation techniques, which combine advanced theories in geostatistics, statistics, engineering, economics and finance, among others, need to be used by the mine analyst or mine planner in order to assess and quantify the existing uncertainty and, consequently, the risk involved in the project investment. Furthermore, current valuation and mine optimisation techniques do not complement each other. That is valuation techniques based on real options (RO) analysis assume an expected (constant) metal grade and ore tonnage during a specified period, while mine optimisation (MO) techniques assume expected (constant) metal prices and mining costs. These assumptions are not totally correct since both sources of uncertainty—that of the orebody (metal grade and reserves of mineral), and that about the future behaviour of metal prices and mining costs—are the ones that have great impact on the value of any mining project. Consequently, the key objective of this thesis is twofold. The first objective consists of analysing and understanding the main sources of uncertainty in an open pit mining project, such as the orebody (in situ metal grade), mining costs and metal price uncertainties, and their effect on the final project value. The second objective consists of breaking down the wall of isolation between economic valuation and mine optimisation techniques in order to generate a novel open pit mine evaluation framework called the ―Integrated Valuation / Optimisation Framework (IVOF)‖. One important characteristic of this new framework is that it incorporates the RO and MO valuation techniques into a single integrated process that quantifies and describes uncertainty and risk in a mine project evaluation process, giving a more realistic estimate of the project’s value. To achieve this, novel and advanced engineering and econometric methods are used to integrate financial and geological uncertainty into dynamic risk forecasting measures. The proposed mine valuation/optimisation technique is then applied to a real gold disseminated open pit mine deposit to estimate its value in the face of orebody, mining costs and metal price uncertainties.

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27

Cai, Wenlong. "Application of network flow and zero-one programming to open pit mine design problems". Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184797.

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An algorithm which adopts a moving cone approach but is guided by maximal network flow principles is developed. This study argues that from a network flow point of view, the re-allocation problem is a major obstacle to prevent a simulation oriented pit design algorithm from reaching the optimum solution. A simulation oriented pit design algorithm can not resolve the re-allocation problem entirely without explicit definition of predecessors and successors. In order to preserve the advantages of moving cone algorithm and to improve the moving cone algorithm, the new algorithm trys to avoid the re-allocation situations. Theoretical proof indicates that the new algorithm can consistently generate higher profit than the popular moving cone algorithm. A case study indicates that the new algorithm improved over the moving cone algorithm (1% more profit). Also, the difference between the new algorithm and the rigorous Lerchs-Grossmann algorithm in terms of generated profit is very insignificant (0.015% less). The new algorithm is only 2.08 times slower than the extremely fast moving cone algorithm. This study also presents a multi-period 0-1 programming mine sequencing model. Once pushbacks are generated and the materials between a series of cutoffs are available for each bench of every pushback, the model can quickly answer, period by period, what is the best (maximum or minimum) that can be expected on any one of these four items: mineral contents, ore tonnages, waste tonnages and stripping ratios. This answer is based on a selected cutoff and considers the production capacity defined by the ore tonnage, the desired stripping ratio and the precedence constraints among benches and pushbacks. The maximization of mineral contents is suggested to be the direct mine sequencing objective when it is permissible. Suggestions also are provided on how to reduce the number of decision variables and how to reduce the number of precedence constraints. A case study reveals that the model is fast and operational. The maximization of mineral contents increases the average grades in early planning periods.

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28

Godoy, Marcelo. "The effective management of geological risk in long-term production scheduling of open pit mines ?" [St. Lucia, Qld.], 2002. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17184.pdf.

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Pelly, Frederick Douglas Peter. "Guidelines to the evaluation of selectively mined, open pit gold deposits during the exploration stage of mine creation". Thesis, Rhodes University, 1992. http://hdl.handle.net/10962/d1005582.

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This dissertation studies the evaluation of selectively mined, open pit gold deposits during the exploration stage of the mine's life. Since 1970 a large number of selectively mined, open pit gold mines have come into operation. The most common deposits include epithermal vein, mesothermal lode and laterite gold deposits. In general the deposits are characterized by small tonnages (1-20 million tonnes), relatively high grades (2-10 grams per tonne gold), submicroscopic to coarse gold, inexpensive mining, and both free milling and refractory ores.The key components that require evaluating during the exploration period are the deposit's geology, ore reserves, pit design, ore metallurgy and environmental impact. Feasibility studies are the main vehicle by which to report and guide the exploration programme. During the exploration period a company may undertake an initial (geological feasibility), second (preliminary mine feasibility) and third (final feasibility) delineation programme in order to gather sufficient data to justify a mine development decision. The responsibility of evaluating the mineral prospect lies primarily with the exploration geologist and mining engineer. Broad experience, a professional attitude, a thorough understanding of mining economics, and a high level of geological, engineering and technical skills are traits required by the evaluators. In order for mining companies to make sound investment decisions the geographical, geological, mining, metallurgical, environmental, marketing, political and financial aspects affecting the economic potential of the venture must be integrated so that the likely costs, risks and returns of the investment alternative are quantified. Ultimately, it is the economic analysis of these three items that determine whether the mineral prospect is developed into a mine I delineated further I retained until economic circumstances improve, or abandoned. To assess the costs, risks and returns, extensive use of the risk analysis is advocated throughout the exploration period . When combined with intelligent judgement of the intangible risk elements, the probabilistic distribution of discounted cash flows are invaluable in making sound investment decisions. However, the economic analysis is only as good as the information on which it is founded. Accurate and representative field data is the most important prerequisite to successfully evaluating and developing a new mine.

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30

Nascimento, Leite Andre. "Stochastic optimization approaches to open pit mine planning : applications for and the value of stochastic approaches". Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=116039.

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The mine production schedule defines the sequence of extraction of selected mine units over the life of the mine, and consequentially establishes the ore supply and total material movement. This sequence should be optimized so as to maximize the overall discounted value of the project. Conventional schedule approaches are unable to incorporate grade uncertainty into the scheduling problem formulation and may lead to serious deviations from forecasted production targets. Stochastic mine production schedulers are considered to obtain more robust mine production schedule solutions.
The application of stochastic approaches to the mine production schedule problem is recent and additional testing is required to better understand these tools and to define the value of a stochastic solution as compared to the conventional result. Two stochastic schedulers are tested in a low-grade variability copper deposit, optimization parameters are discussed and their results compared with a conventional schedule.
The first method uses a stochastic combinatorial optimization approach based on simulated annealing to address the mine production schedule problem. The method aims for maximization of the net present value (NPV) of the project and minimization of deviations from the production targets. These objectives are attained by incorporating grade uncertainty into the mine production schedule problem formulation. The second method formulates the problem as a stochastic integer programming problem, in which the objective is the maximization of the projects' NPV and the minimization of production targets deviations. The model can also manage how the risk of deviating from the targets is distributed between production periods.
Both stochastic approaches were tested in a low-grade variability copper deposit. In both case studies, the value of a stochastic solution is demonstrated to be higher than the conventional one. This fact demonstrated the misleading results that a conventional schedule may produce and shows the importance of not ignoring the presence of uncertainty when defining the mine production schedule for a project.

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Duzgun, Ozkan. "Assessment Of Velocity Of Detonation At Kumtor Open Pit Gold Mine". Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613676/index.pdf.

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One of the most important properties of an explosive is its velocity of detonation (VOD). It is essential that the explosive should detonate at its optimum rate and release sufficient detonation pressure to get good fragmentation under the existing field conditions. The main objectives of this research study are to investigate the effects of explosive type, blast hole diameter, and degree of confinement on the VOD of bulk ANFO and bulk emulsion in Kumtor Open Pit Gold Mine. In this study, the continuous resistance wire method is employed to measure in-situ VOD of both bulk ANFO and bulk emulsion. The VOD values are measured for different hole diameters and under different confinements for both explosives. The ideality of bulk ANFO and bulk emulsion is calculated by comparing the in-situ measured VOD&rsquo
s and their ideal detonation values. It is found that the VOD of both explosives increases as the blast hole diameter and the degree of confinement increases. In addition to this, VOD of bulk ANFO decreases when it gets wet in the blast hole. Another finding is that, proportion of bulk emulsion ingredients has influence on its VOD. This research study provides a good understanding to use suitable explosive in existing rock conditions in Kumtor Open Pit Gold Mine.

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Сістук, Володимир Олександрович, Владимир Александрович Систук i Volodymyr O. Sistuk. "Підвищення показників маневреності кар’єрних самоскидів з електромеханічною трансмісією". Thesis, Друкарня ФОП Щербенюк С. Г, 2014. http://eadnurt.diit.edu.ua:82/jspui/handle/123456789/2267.

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Сістук, В. О. Підвищення показників маневреності кар'єрних самоскидів з електромеханічною трансмісією : авт. дис. к. т. н.: 05.22.12 / В. О. Сістук ; Дніпропетр. нац. ун-т залізн. трансп. ім. акад. В. Лазаряна. - Д., 2014. - 20 с. : іл., табл. ГРНТИ 52 УДК 622.271.33:629.3.072.4(043.3) Захист – 22 травня 2014 р.
UK: АНОТАЦІЯ Дисертацію присвячено підвищенню показників маневреності кар’єрних самоскидів з електромеханічною трансмісією. Вперше науково обґрунтовано можливість та доцільність застосування примусового управління обертанням задніх ведучих коліс кар’єрного самоскида з електромеханічною трансмісією, що дозволяє їм виконувати маневри із використанням силового довороту. Вперше розроблено математичну модель силового довороту, яка дозволяє визначити відношення кутових швидкостей задніх ведучих коліс окремо правого і лівого борту машини і її показники маневреності відповідно до коефіцієнта зчеплення на основі вперше встановлених аналітичних залежностей. Аналітична залежність відношення кутових швидкостей задніх ведучих коліс від коефіцієнта зчеплення доведена методом лабораторного експерименту на створеній лабораторній моделі, яка дозволяє моделювати процес виконання маневру колісною машиною при різних способах повороту. Створено алгоритм примусового управління обертанням задніх коліс кар’єрного самоскида, оснащеного електромеханічною трансмісією. Відповідно до розробленого алгоритму управління виготовлено електронний блок, який разом із додатковою датчиковою апаратурою, що встановлюється на кар’єрний самоскид БелАЗ-7513В, представляє собою систему примусового управління поворотом.
RU: АННОТАЦИЯ Диссертация посвящена вопросу улучшения маневренности карьерных самосвалов с электромеханической трансмиссией для повышения эффективности их работы в стесненном пространстве рабочих зон глубоких карьеров. В работе проведен комплекс теоретических, лабораторных, промышленных исследований маневренности карьерных самосвалов с электромеханической трансмиссией при выполнении маневров с применением силового доворота. Разработана математическая модель силового доворота колесной машины. Впервые установлена аналитическая зависимость отношения угловых скоростей задних ведущих колес отдельно правого и левого борта от коэффициента сцепления, которая позволяет разработать рациональный алгоритм принудительного управления вращением задних колес карьерного самосвала. Впервые установлены аналитические зависимости, позволяющие определить показатели маневренности колесной машины на основе требуемого отношения угловых скоростей задних ведущих колес. Математическое моделирование с использованием разработанной модели позволило установить, что для карьерного самосвала БелАЗ-7513 минимальный радиус поворота в сложных условиях эксплуатации (на увлажненном грунтовом покрытии основных трасс с коэффициентом сцепления φ=0,34) при выполнении маневра с использованием силового доворота может быть уменьшен с 13,0 до 10,1 м. Установленные математические зависимости проверены экспериментальным путем с применением лабораторной модели, созданной в соответствии с масштабным коэффициентом, равным 12,0, в качестве которого выступало отношение радиуса колеса карьерного самосвала к радиусу колеса модели. Лабораторная модель позволяет моделировать процесс выполнения маневра колесной машиной при различных способах поворота путем принудительного воздействия на частоты вращения электродвигателей задних колес. Разработан и реализован на карьерном самосвале БелАЗ-7513В в условиях ПАО «Центральный ГОК» алгоритм принудительного управления вращением задних колес карьерного самосвала с электромеханической трансмиссией. Отклонение между расчетным 100 % (1,12 м) минимальным радиусом поворота лабораторной модели и полученным в результате эксперимента составило 10,7 % (1,0 м), отклонение между расчетным 100% (10,38 м) минимальным радиусом поворота карьерного самосвала и полученным путем промышленных испытаний составило 7,9 % (11,30 м), что подтвердило соответствие аналитических и экспериментальных показателей. Использование системы принудительного управления поворотом на карьерных самосвалах с электромеханической трансмиссией позволяет повысить техническую производительность машин на 6,1 % путем уменьшения времени их маневрирования до 1,4 мин, установленного с помощью хронометража в промышленных условиях, а также позволяет снизить топливо-энергетические затраты на 2,3 %. Материалы диссертационных исследований приняты на предприятиях ПАО «Центральный ГОК», ПАО «АрселорМиттал Кривой Рог» и ООО «Кривбасс-БелАЗ-Сервис СП». Расчетный экономический эффект в условиях ПАО «АрселорМиттал Кривой Рог», полученный за счет повышения производительности карьерных самосвалов БелАЗ-7513 на 5,9%, для существующего парка из 8 машин составил 678,0 тыс. грн. / год. Таким образом, впервые научно обоснованы возможность и целесообразность применения принудительного управления вращением задних ведущих колес карьерного самосвала с электромеханической трансмиссией при маневрировании, что обеспечивает уменьшение радиуса поворота машины, повышая производительность промышленного автотранспорта карьеров.
EN: THE SUMMARY The thesis is dedicated to increasing of open pit trucks with electrical transmission indices of maneuverability. For the first time there has been scientifically grounded possibility and suitability of usage of forced controllability of rear leading wheels of open pit truck with electrical transmission that enables them to carry out maneuvers with the usage of a forced additional turn. For the first time there has been worked out mathematical model of a forced additional turn which enables to determine a correlation of angular velocity of rear leading wheels of starboard and port sides of a car and its indices of maneuverability relative to a friction coefficient on the basis of firstly determined analytical dependence. Analytical dependence of relation of rear leading wheels angular velocity to a friction coefficient has been proved with laboratory experiment method on a created laboratory model which enables to simulate the process of a wheel vehicle maneuver performing with various means of a turn. An algorithm of a forced controlling of rear wheels rotation of open pit truck with electrical transmission has been created. In accordance with the created algorithm an electrical block which coupled with additional sensor equipment that is installed on a pit truck BelAZ-7513B representing a forced turn controlling system has been manufactured.
Криворізький національний університет

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Buyukyildirim, Kursad. "Ground Vibration Assessment At Y-3 Panel Of Tuncbilek Open Pit Lignite Mine". Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606668/index.pdf.

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village is within the close neighbourhood of the Western Lignite Corporation Y-3 panel. Although the nearest part of the mine is 1100 m and the farthest part is 2500 m from the village at present, some of the villagers complained about the ground vibration at the past. Therefore the assessment of damage risk and, if any, control and minimization of vibrations constitutes the aim and the scope of this research work. The researh work consists of monitoring of vibration, characterising of the seismic waves by full wave form analysis, and determination of magnitude and frequency of the waves from round blasting practice. Also dominant frequencies are determined, using single-hole blasting records by special software. The analyses are continued by a critical discussion and evaluation, and, proposals for new firing methods are made. The proposed firing methods are validated by further monitoring. As a result the best blasting practice was selected and offered to control and minimize the ground vibration.

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Rodovalho, Edmo da Cunha. "An innovative approach for controlling operational parameters in open pit mining to reduce costs and environmental impacts". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/3/3134/tde-18012017-151352/.

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The main current challenges of the mining industry include aspects such leveraging the mine productivity, controlling costs and reducing environmental impacts. In most surface mining operations, overburden removal requires haulage over short distances. A comparison of different haulage options for short distances with respect to energy efficiency in open-pit mining is a key aspect for decision making, but only a limited number of recent research efforts have considered energy efficiency as a control variable in mining projects. Loading and haulage have an energy source that is highly dependent on fossil fuels. In addition, the equipment involved in these operations use tyres as an important input. There are many studies relating the fuel consumption and tyre wear to several performance indicators, but a methodology that identifies and prioritizes higher-impact variables under each specific operating condition is not available. This research proposes new methods using alternative equipment simulations for fuel consumption and tyre wear management. Such methods include multiple regression analysis, stochastic simulation and specialized software routines in order to identify and control operational performance variables related to diesel consumption, tyre wear and selection of new alternatives equipments. Considering alternative scenarios of equipment models, the results of the proposed method include a 14% reduction in specific fuel consumption and a 16% increase in productivity. Regarding the fuel management method, the reduction of diesel consumption reached 10%. For the tyre wear management method, the results indicated a potential to save up to 8.9 t of tyre rubber in only one quarter.
Na atualidade, a indústria de mineração possui como principal desafio alavancar sua produtividade, controlar custos e reduzir impactos ambientais. Muitas operações de mineração exigem transporte em pequenas distâncias. A comparação de diferentes opções de transporte em distâncias curtas considerando a eficiência energética é uma necessidade de operações de lavra a céu aberto, mas existem poucos estudos recentes que priorizam esta variável em projetos de mineração. As operações de carga e transporte são amplamente dependentes de combustíveis fósseis. Essas operações também necessitam de pneus como um importante insumo. Existem alguns trabalhos que relacionam o consumo de combustíveis e o desgaste dos pneus a variáveis operacionais, mas uma metodologia que identifique as variáveis de maior impacto frente a condições específicas ainda não está disponível. O presente trabalho fornece novos métodos de simulação para equipamentos alternativos, consumo de combustíveis e gestão do desgaste de pneus. Análises de regressão linear múltipla, simulações e ferramentas de desenho de mina permitem identificar e controlar variáveis ligadas ao consumo de combustíveis, desgaste de pneus e seleção de equipamentos. Os estudos envolvendo equipamentos alternativos alcançaram uma redução de 14% no consumo de diesel e um aumento de 16% na produtividade. Com relação às técnicas de gestão do consumo de combustível aplicada aos caminhões observou-se uma redução de 10%. Considerando o sistema de gestão de desgaste de pneus, a aplicação do método proposto possui um potencial de evitar o descarte de 8,9 t de borracha para pneus em apenas um trimestre.

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Schäfer, Fábio. "Desenvolvimento de uma sistemática de melhoria do desempenho econômico de indústrias extrativas : o caso de uma mineração a céu aberto". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/61383.

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Em função da globalização, os ambientes empresariais estão se tornando mais competitivos; assim, aumenta a preocupação e a necessidade de se prover um sistema de informações gerenciais que seja eficaz, confiável e relevante para auxiliar os gestores a tomarem decisões inteligentes. Com a utilização de princípios e métodos de custeio vinculados aos serviços inerentes aos métodos e operações de lavra, este trabalho tem como primeiro objetivo identificar e compreender as deficiências dos atuais sistemas de custeio e de produção e estruturar uma sistemática que apoie a avaliação do desempenho econômico-financeiro nas minerações a céu aberto. O segundo objetivo deste trabalho é utilizar o método do custo-padrão vinculado à produção e às regras de negócio e validá-lo mediante a comparação do realizado versus previsto nas minerações a céu aberto, através da utilização de conceitos de desperdícios, do princípio do custeio por absorção parcial, do controle e gestão de custos e de produção para avaliação de resultados. A unidade de extração mineral estudada utiliza o método de lavra por bancadas em cava e terceiriza as operações de descobertura, perfuração, detonação, escavação, carregamento e transporte. A empresa contratada utiliza o princípio de custeio por absorção total e o método de custeio de centros de custos. Assim, a sistemática que apoia a avaliação do desempenho econômico-financeiro juntamente com o método do custo-padrão foi validada e desenvolvida em três serviços terceirizados com o objetivo de verificar a sua funcionalidade e a sua praticidade. Portanto, as novas informações gerenciais auxiliam o gestor identificar a produtividade e a lucratividade do empreendimento e os resultados dos serviços e de suas operações, além de todos os custos gerenciais já existentes.
In the light of globalization, the enterprise environments are becoming more competitive; thus, increases the concern and the need to provide a management information system that is effective, reliable and relevant to assist managers to make intelligent decisions. With the use of principles and costing methods linked to services inherent in mining operations and methods, this work is intended mainly identify and understand the weaknesses of the current costing and production system and structure a systematic that supports performance evaluation productive-economic-financial in surface mining. The second objective of this work is to use standard cost method linked to production and business rules and validate it by comparing the accomplished against foreseen in surface mining, through the use of concepts of wastes, the principle costing of partial absorption, cost control and management for production to evaluation of results. The mineral extraction unit studied uses the open pit mining method and outsources the mining operations of pre stripping, drilling, blasting, rock excavation, loading and transportation. The outsourced company uses the costing principle of total absorption and the costing method is the cost centers. Thus, the systematic that support the evaluation of productive-economic-financial performance and the standard cost method were developed and validated in three outsourced services with the goal of verifying its functionality and practicality. Therefore, the new management information assists the manager to identify the productivity and profitability of the enterprise and the results of its operations and services, in addition to all of the existing management costs.

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Carvalho, Mara Gilene Alves de. "Estratégia ambiental pró-ativa: sequenciamento de lavra concomitante com a disposição de estéril dentro da mina". Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/3/3134/tde-03072009-150534/.

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Este trabalho propõe uma metodologia inovadora de seqüenciamento de lavra em minério de ferro a qual, além de considerar os parâmetros operacionais e econômicos das técnicas tradicionais, permite uma abordagem ambiental proativa para sequenciar a lavra de forma a antecipar a exaustão de parte da cava para disposição do estéril dentro da cava final. A metodologia proposta de seqüenciamento ordenado de lavra permite reduzir a área degradada a ser reabilitada na mina, com significativos benefícios associados à reducão do impacto ambiental, sem comprometer as metas de produtividade e competitividade econômica da lavra. A metodologia de seqüenciamento ordenado de lavra foi aplicada em um estudo de caso de projeto de lavra de minério de ferro, e os resultados alcançados comprovaram os benefícios esperados com a aplicação da metodologia proposta.
This paper presents a innovative approach for an environmentally pro-active mine scheduling process. The proposed methodology has been developed for identifying a mine sequence that meets all operational and economical constraints in iron-ore mining, and takes into account a pro-active approach for scheduling the mine according to environmental criteria. The proposed methodology allows a significant reduction of the environmental impact related to the mining operation without compromising productivity and the economical feasibility of the mine. The methodology has been applied to a case study of iron ore mining in Brazil, where the expected benefits have been proven.

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De, Carli Carla. "Análise de projetos limite : lavra a céu aberto x lavra subterrânea". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/77760.

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Com o passar dos anos a sociedade tem se tornado gradativamente mais dependente de recursos minerais para o seu funcionamento e para o desenvolvimento de produtos. A maior parte das coisas que cercam o homem necessita de alguma espécie de bem mineral como matéria prima para sua fabricação. Por isso, cada vez mais, a mineração tem sido objeto de estudos, buscando aprimoramento e desenvolvimento nos métodos de extração de minérios. Existem duas formas utilizadas para a extração de bens minerais, uma por uso de métodos de lavra a céu aberto (OP) e outra através da aplicação de métodos para lavra subterrânea (UG). A definição de qual método deve ser aplicado em cada caso depende de diversos fatores, como profundidade e geometria do corpo mineral, competência da rocha portadora do minério e da rocha encaixante, entre outros, mas ao final, aspectos econômicos predominam para a definição da viabilidade de cada um dos possíveis métodos. Porém, existem casos em que a melhor escolha para minerar o depósito não se dá por umas dessas duas opções, e sim, pela combinação de ambas, ou seja, a aplicação da lavra a céu aberto seguida da extração dos recursos remanescentes por lavra subterrânea. A grande dificuldade, nestes casos, é definir qual o momento ideal para a transição de método, de maneira que os resultados do projeto integrado sejam otimizados e que um método não inviabilize o outro. Para isso é necessário analisar as duas opções de lavra individualmente, lavrando somente a céu aberto e lavrando somente por métodos subterrâneos, além de analisar-se a viabilidade do projeto através da combinação dos dois métodos, comparando as opções técnica e economicamente e selecionando a que apresente a melhor resposta ao final, para então tomar-se a decisão de qual alternativa de projeto é o mais indicado para cada caso.
Over the years, the society has become progressively dependent on mineral resources for its operation and for development of products. The majority of the things that surround the men needs some kind of mineral material as raw material for its manufacture. Therefore, increasingly, mining has been studied aiming to improve and develop methods of mineral extraction. There are two ways that are utilized to mineral extraction, one by open pit methods (OP) e another by application of underground methods (UG). The definition of which one should be applied in each case depends on many factors, such as depth and geometry of the mineral body, strength of the mineralized and bounding rock, among others, but at the end, economic aspects are predominant for the definition of viability of the methods. However, there are some cases where the best choice to mine the deposit is not one of these options, but the combination of both methods, it means, the application of open pit mining followed by extraction of remaining resources by underground mining. The great challenge, in these cases, is to define what is the right moment for the transition of the methods, making sure that the results are optimized and one method do not impede the development of the other one. In this sense, it is necessary to analyze both options individually, mining the deposit only by open pit and mining only by underground, and also analyze the combination of the two methods, comparing these options technically and economically at the end, and then decide which project alternative is the best for each case.

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Zamora-Paredes, V., V. Zamora-Paredes, L. Arauzo-Gallardo, C. Raymundo-Ibanez i Moises Perez. "Optimal mesh design methodology considering geometric parameters for rock fragmentation in open-pit mining in the Southern Andes of Peru". Institute of Physics Publishing, 2020. http://hdl.handle.net/10757/651802.

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Blasting is one of the most important stages in the productive process of a mine due to its direct impact on rock fragmentation, which determines the degree of productivity of operations and the extraction costs generated. In this scenario, an optimized methodology is presented for designing blasting meshes by using mathematical models that help calculate the geometric parameters of a blasting mesh, such as burden, considering the variables of the rock mass and the type of explosive to measure its impact on rock fragmentation and loading productivity (tons/hour). The main advantage of this method is the reliability of the design, which takes into account a greater number of variables that influence fragmentation and uses the principle of distribution and amount of energy in an optimal way. The results obtained in the case of application show that a change in design (2.7 x 2.7 square mesh to 2.2 x 2.5 triangular mesh) reduces P80 by 65%, from 17 to 6 inches, approximately. Additionally, the results show that greater operational efficiency was achieved by increasing excavator productivity by approximately 15.6%.

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Neshuku, Martha Nyambali. "Comparison of the performance of two atmospheric dispersion models (AERMOD and ADMS) for open pit mining sources of air pollution". Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/25835.

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The performance of the AERMOD and ADMS dispersion models was tested using PM10 (thoracic dust) emissions from Rössing Uranium Mine open pit in Namibia. The performance of the two models was evaluated against the observations and also against each other using various statistical measures. The models were tested under different case scenarios (cases explained in chapter 4) with the aim of evaluating their performances as well as their inter model variability. The study was undertaken from the 13 July 2009 – 14 August 2009. The results from the study showed that the performance of ADMS was superior to that of AERMOD. In general, the performance of AERMOD was very poor and simulated extremely high concentration values. AERMOD performed even more poorly during calm conditions. ADMS performance was superior to AERMOD as was evident from the values of various performance statistical measures and a conclusion reached was that ADMS is likely to be a better model to use in cases where prolonged calm conditions are experienced. Copyright
Dissertation (MSc)--University of Pretoria, 2012.
Chemical Engineering
unrestricted

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Shu, Biao. "Rock Slope Stability Investigations In Three Dimensions For A Part Of An Open Pit Mine In USA". Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/338701.

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Traditional slope stability analysis and design methods, such as limit equilibrium method and continuum numerical methods have limitations in investigating three dimensional large scale rock slope stability problems in open pit mines associated with stress concentrations and deformations arising due to intersection of many complex major discontinuity structures and irregular topographies. Analytical methods are limited to investigating kinematics and limit equilibrium conditions based on rigid body analyses. Continuum numerical methods fail to simulate the detachment of rock blocks and large displacements and rotations. Therefore, there is an urgent need to try some new methods to have a deeper understanding of the open pit mine rock slope stability problems. The intact rock properties and discontinuity properties for both DRC and DP rock formations that exist in the selected open pit mine were determined from tests conducted on rock samples collected from the mine site. Special survey equipment (Professor Kulatilake owns) which has a total station, laser scanner and a camera was used to perform remote fracture mapping in the research area selected at the mine site. From remote fracture mapping data, the fracture orientation, spacing and density were calculated in a much refined way in this dissertation compared to what exist in the literature. Discontinuity orientation distributions obtained through remote fracture mapping agreed very well with the results of manual fracture mapping conducted by the mining company. This is an important achievement in this dissertation compared to what exist in the literature. GSI rock quality system and Hoek-Brown failure criteria were used to estimate the rock mass properties combining the fracture mapping results with laboratory test results of intact rock samples. Fault properties and the DRC-DP contact properties were estimated based on the laboratory discontinuity test results. A geological model was built in a 3DEC model including all the major faults, DRC-DP contact, and two stages of rock excavation. The built major discontinuity system of 44 faults in 3DEC with their real orientations, locations and three dimensional extensions were validated successfully using the fault geometry data provided by the mining company using seven cross sections. This was a major accomplishment in this dissertation because it was done for the first time in the world. Numerical modeling was conducted to study the effect of boundary conditions, fault system and lateral stress ratio on the stability of the considered rock slope. For the considered section of the rock slope, the displacements obtained through stress boundary conditions were seemed more realistic than that obtained through zero velocity boundary conditions (on all four lateral faces). The fault system was found to play an important role with respect to rock slope stability. Stable deformation distributions were obtained for k₀ in the range of 0.4 to 0.7. Because the studied rock mass is quite stable, it seems that an appropriate range for k₀ for this rock mass is between 0.4 and 0.7. Seven monitoring points were selected from the deformation monitoring conducted at the open pit mine site by the mining company using a robotic total station to compare with numerical predictions. The displacements occurred between July 2011 and July 2012 due to the nearby rock mass excavation that took place during the same period were compared between the field monitoring results and the predicted numerical modeling results; a good agreement was obtained. This is a huge success in this dissertation because such a comparison was done for the first time in the world. In overall, the successful simulation of the rock excavation during a certain time period indicated the possibility of using the procedure developed in this dissertation to investigate rock slope stability with respect to expected future rock excavations in mine planning.

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Esenkaya, Ercan. "Investigation Into The Effect Of Meteorological Parameters On The Airborne Dust Concentration At Ovacik Open Pit Gold Mine". Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12604938/index.pdf.

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In this thesis, it is aimed to investigate and analyze the effect of meteorological conditions on airborne dust measured at Ovacik Open Pit Gold Mine. Meteorological data must be sound and reliable which are used mainly to design an air model to predict the effect of industrial sites on air quality during production. Wind speed, wind direction, airtemperature, air pressure, relative humidity, rainfall, evaporation and sunshine. are the parameters investigated in this study. In the thesis, the meteorological data observed are analyzed and discussed together with the airborne dust measured by MP101M Suspended Particulate Beta Gauge Monitor at Ovacik Gold Mine. In this study, the most significant meteorological parameter affecting airborne dust concentration is determined as air temperature. In this study, it is also determined through airborne dust measurements that neither the short-term limit nor the long-term limit has been exceeded. Therefore, the airborne dust concentrations at Ovacik Gold Mine comply with the Turkish Air Quality Control Regulation.

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Klingmann, Scot. "The application of a digital photogrammetry system to structural mapping at a large open pit mine". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ37959.pdf.

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Qureshi, Muhammad Asim. "An Implementation of Ant Colony and Genetic Algorithm based Hybrid-Metaheuristic for Cut-off Grade Optimization in Open-Pit Mining Operations". Thesis, Curtin University, 2017. http://hdl.handle.net/20.500.11937/68406.

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This study presents a new mathematical model for cut-off grade and production scheduling optimisation in open pit mining operations. The model maximises the net present value of the operation subject to the mining precedence, production capacity, and grade-blending constraints. A solution using exact method establishes the computational complexity of the model. Consequently, a hybrid-metaheuristic is developed to solve practical instances of the model. Performance evaluation reflects an acceptable gap between the exact and heuristic solutions.

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Vieira, João Carlos. "Determinação e quantificação de elementos de relevância em infraestrutura de mina". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/115577.

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Este estudo apresenta, de forma sistemática, a importância da infraestrutura de mina a céu aberto, determinando as atividades principais dessa fase e os impactos e benefícios causados por alterações na forma de execução, medidos através de indicadores de produtividade e resultados financeiros. Algumas atividades principais como a reconfiguração das faces dos bancos de lavra pela aplicação comparativa de desempenho de trator de esteira e retroescavadeira; o estabelecimento de padrão para o dimensionamento das camadas estruturais e funcionais das estradas de mina; a mensuração dos benefícios da construção e manutenção das estradas, no desempenho dos caminhões e dos tratores de esteira, através de estudos de caso e demonstrar que a aplicação de técnicas adequadas modificam o resultado operacional. A metodologia utilizada aborda a relevância da infraestrutura e da frota de equipamentos auxiliares dentro do ciclo operacional, propondo uma aplicação correta e sistemática, baseada na demanda e nas atividades auxiliares que proporcionam condições operacionais para as atividades "que geram valor", suportando o cumprimento das metas estabelecidas no plano de produção. Os principais resultados obtidos vão desde a melhoria da segurança operacional, da imagem da empresa, do resultado financeiro, ao melhor aproveitamento dos recursos minerais, impactando diretamente a sustentabilidade do negócio. Através dos casos abordados neste trabalho, conclui-se que o desempenho da mineração a céu aberto é fortemente dependente do foco dado à infraestrutura de mina, ou seja: da qualidade das pistas, adequação das praças de carregamento, condição operacional de pilhas de estéril ou minério, drenagem superficial, dos métodos de trabalho e da disciplina operacional, gerando ganhos e/ou perdas que vão de unidades de porcentagem a várias vezes a capacidade do processo abordado.
This study presents, in a systematic way, the importance of the infrastructure in the open pit mining, determining the main activities of this operation and the impacts and benefits from changes implemented measured by operating productivity indicators and financial results. Some major activities such as the reconfiguration of the slope faces by the comparative performance of bulldozer and backhoe; the establishment of standards for the design of structural and functional layers of the mine haul roads; measure the benefits of the construction and maintenance of roads, the performance of trucks and bulldozers, through case studies show that the application of appropriate techniques can modify the operating result. The methodology addresses the importance of infrastructure and auxiliary equipment fleet in the operating cycle, proposing a correct and systematic application, based on demand and auxiliary activities that provide operating conditions for activities "that create value", supporting the achievement of the goals established in the production plan. The main results ranging from improved operational safety, company image, financial results, the best use of mineral resources, directly impacts on the business sustainability. Through the cases discussed in this work, it is concluded that the performance of the open pit mining is strongly dependent on the focus given to the mine infrastructure wich means, the quality of the tracks, adequacy of the loading spots, operating condition of waste dumps or ore bins, surface drainage, working methods and operational discipline, generating gains and/or losses ranging from small amounts to several times the capacity of the covered process.

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G, Mastrorocco. "Use of innovative technologies for the analysis of brittle failure mechanisms applied to underground and open pit marble mines". Doctoral thesis, Università di Siena, 2018. http://hdl.handle.net/11365/1039639.

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The exploitation of rock material usually results in a change of the in-situ force field surrounding the rock mass. Mine design is one of the major challenges when planning and operating a mine in a complex environmental context such as the Apuan Alps marble district (Italy). There could be significant risks related to the safety of both personnel and equipment. This research focuses on data collection, geo-structural interpretation and rock mechanics analysis by means of advanced remote sensing techniques (e.g. Structure for Motion methods, Terrestrial Laser Scanning, change detection analysis, etc.), numerical modelling for the stability analysis of both surface and underground structures, and modelling of brittle failure. In particular, this research investigates the application of Remotely Piloted Aircraft Systems (RPASs) and of Structure from Motion (SfM) methods for geo-hazard identification, awareness and risk reduction. Limit equilibrium and numerical analyses were carried out to study the stability of two large marble blocks in an open pit marble mine area. These analyses were focused on the important role that rock bridges have on slope stability, and to investigate the active-passive wedge mechanism that may develop due to rock mass strength degradation and brittle failure mechanisms. Additionally, the spalling failure of an underground marble pillar was investigated to include a multifaceted/multitemporal stability analysis with the objective of studying mining engineering issues related with the extraction of valuable rock resources. Morphological variations were identified using a change detection approach and analysed using both Finite Element (FEM) and hybrid Finite-Discrete Element (FDEM) methods. In this context, understanding the mechanical behaviour of a rock mass has always been a major concern for increasing the safety and minimizing economic loss. A mine design concerns the stability of the excavations, including the potential collapse of slopes and quarry faces, spalling of the sidewalls, and the structurally controlled failure of the underground openings. The cornerstone of an engineering understanding of a rock mass structure is represented by data collection and interpretation. The starting point is represented by the knowledge of the lithologies and the major structural features present in the rock mass. Such information provides essential background to rock mechanics studies, but may be available in limited form using classical mapping techniques due to the limited accessibility of rock outcrops. Indeed, measurements can be made on natural slopes or on faces exposed by surface excavations, but the data collected may not be representative of the whole site. In this context, it is now possible to drastically increase the quantity of mapping information by using advanced and modern geomatics techniques. In order to analyse rock outcrops, the use of RPAS allows to overcome data acquisition issues related to high steep quarry walls, while at the same time it provides high resolution images and 3D models. This is particularly important because fractures characteristics may be spatially variable due to stress relaxation induced by excavation activity. Terrestrial Laser Scanning allows to rapidly acquire information as point clouds with a millimetre level of detail from the surrounding surfaces. Both aerial and terrestrial measurement techniques can be useful to perform detailed and accurate structural analysis and periodical estimates of surface changes by means of the so-called change detection analysis, in order to identify modified surfaces in the mining area. In this context, geomatics techniques and conventional geological/engineering-geological surveys techniques should be used simultaneously because when used together they allow to reduce data uncertainty and to provide a better characterisation of data variability. Indeed, the reliability of the analysis depends on the quality, quantity and interpretation of available field information. Many design structures in mine engineering practice involve complex problems and it is often necessary to carry out detailed rock mechanics analysis using powerful numerical tools. Indeed, stress and stability analysis can be carried out using continuous and/or discontinuous numerical approaches. These techniques are currently used in the civil and mining engineering sectors due to the possibility to take account of complex rock mass deformation and failure. Numerical methods allow to consider the whole rock mass mechanical behaviour on the contrary of classical approaches that, for example, consider a block as an isolated object. In this context, numerical methods are able to investigate and illustrate the involved rock failure mechanisms during mining activities and particularly the initiation, propagation, and coalescence of cracks, and the propagation of discrete fractures.

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Zhao, Lei. "Three-dimensional numerical study on the batter instability mechanism of Maddingley Brown Coal Open Pit, Victoria, Australia using PLAXIS 3D". Thesis, Federation University Australia, 2019. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/172972.

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With the increased size of excavation due to long-term open cut mining, batter instability has become a major geo-hazard in Victorian Brown Coal Open Pits where facilitate some largest brown coal mining operations in the world. Block failure is a unique failure mode in Victorian brown coal mines, which is often associated with cracks and rainfall. Maddingley Brown Coal Mine (MBC) is located in Bacchus Marsh, Victoria, Australia. Slope instability has also been a major geo-problem since the open pit mining commenced in MBC in 1940s. Making clear the cracking mechanism and the correlations between rainfall and batter instability have important implications in better understanding and predicting batter failures in Victorian brown coal mines. In this research, three-dimensional geologic models were developed to investigate the mechanism of brown coal batter instability. The finite element program encoded in Plaxis 3D was employed to conduct the complex two-phase (fluid-solid) coupled numerical simulations. The results revealed the cracking mechanism of coal batter and the effects of rainfall on batter stability. It was found that the brown coal batter with overburden tends to lead a circular critical path while the batter after overburden removal shows a trend of block sliding as interpreted by the shear and tensile strains simulated. The existence of joints and the hydrostatic water pressure in the joints could adversely affect the stability of brown coal batter towards block failure. Precipitation can increase the deformation, excess pore pressure, total pore pressure, active pressure and decrease the matric suction, and thereby decrease the shear strength, effective stress, and batter stability. The results from the three-dimensional hydro-mechanically coupled finite element study were well agreed with the field monitored data, theoretical calculations, and Victorian brown coal mining experience.
Doctor of Philosophy

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Hoang, Hoa Thi Bich [Verfasser], Reto [Akademischer Betreuer] Gieré i Stefan [Akademischer Betreuer] Hergarten. "Mineralogical and chemical characterization of airborne dust particles and their environmental effects in the open-pit coal mining area in Quang Ninh, NE Vietnam". Freiburg : Universität, 2017. http://d-nb.info/1149507756/34.

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Koerting, Friederike Magdalena [Verfasser], Uwe [Akademischer Betreuer] Altenberger, Helmut [Akademischer Betreuer] Echtler, Uwe [Gutachter] Altenberger, Konstantinos [Gutachter] Nikolakopoulos i Christian [Gutachter] Rogass. "Hybrid imaging spectroscopy approaches for open pit mining : applications for virtual mine face geology / Friederike Magdalena Koerting ; Gutachter: Uwe Altenberger, Konstantinos Nikolakopoulos, Christian Rogass ; Uwe Altenberger, Helmut Echtler". Potsdam : Universität Potsdam, 2021. http://d-nb.info/1230494170/34.

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Özdemir, Ismet [Verfasser], Per Nicolai [Akademischer Betreuer] Martens i Christian [Akademischer Betreuer] Niemann-Delius. "A Decision Support System and Cost-Performance Analysis for Dust Control at Open-Pit Coal Mines / Ismet Özdemir ; Per Nicolai Martens, Christian Niemann-Delius". Aachen : Universitätsbibliothek der RWTH Aachen, 2015. http://d-nb.info/1127143654/34.

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Candia, Renan Collantes. "Escavação de rochas com furos de grande diâmetro na mineração a céu aberto". Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/3/3134/tde-19092006-160821/.

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Esta dissertação apresenta uma revisão bibliográfica dos principais aspectos envolvidos nas operações de escavação de rochas com furos de grande diâmetro na mineração a céu aberto. O trabalho expõe o método de perfuração rotativa por ser o mais utilizado na execução desta operação unitária de lavra. Faz-se também um estudo dos principais agentes de desmonte que contribuem no emprego de furos de grande diâmetro na indústria da mineração, especialmente na explotação de minérios metálicos. São analisadas as propriedades do maciço rochoso, na determinação da carga específica e sua influência nos resultados da escavação de rochas por explosivos. É realizada ainda uma análise da metodologia utilizada para o dimensionamento do plano de fogo, baseando-se na inter-relação existente entre seus diversos elementos geométricos. Apresenta-se também a teoria de crateras como uma metodologia alternativa para dimensionamento de plano de fogo. Finalmente mostram-se os principais impactos ambientais decorrentes da detonação de explosivos na escavação de rochas.
This dissertation presents a bibliographical review of the main aspects involved in the open pit blasting operation using large diameter blastholes. The work displays the method of rotary drilling, being the most frequent used in the execution of this mining unitary operation. Here is presented a study of the main blasting agents that contribute to the increasing application of large diameter blastholes in the mining industry, especially in the field of metallic ores. The properties of the rock mass are analysed, in the determination of the powder factor and its influence on the results of rock excavation by explosives. An analysis of the methodology used for the determination a shot plan is carried out based on the existing interrelation between diverse geometric elements involved. The crater theory is also presented as an alternative methodology for the same purpose. Finally, the main environmental impacts caused by blasting in the rock excavation are discussed.

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