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Articles 1 - 30 of 33

Full-Text Articles in Mining Engineering

Wall Control Blasting At The Orphan Boy Mine – Butte, Montana, Jewel Sakyi Apr 2019

Wall Control Blasting At The Orphan Boy Mine – Butte, Montana, Jewel Sakyi

Graduate Theses & Non-Theses

Blasting is often conducted to produce desirable fragment sizes to minimize production cost and energy consumption in downstream processes, including loading, hauling, and crushing. However, the venting of explosive energy in the rock formation sometimes causes unwanted damage beyond the desired perimeter of the blast area. Control blasting has mainly been used in surface mining operations to minimalize blast damage. To explore the applicability of control blasting in underground mining operations, protect the safety of students, faculty, and staff, prevent overbreak, and to ensure the stability of openings and workings, four experimental control blasts, comprising of three smooth blasts and ...


The Status Of The Local Community In Mining Sustainable Development Beyond The Triple Bottom Line, Sisi Que, Liang Wang, Kwame Awuah-Offei, Yao Chen, Wei Yang Feb 2019

The Status Of The Local Community In Mining Sustainable Development Beyond The Triple Bottom Line, Sisi Que, Liang Wang, Kwame Awuah-Offei, Yao Chen, Wei Yang

Kwame Awuah-Offei

Mineral products provide essential fuels and raw materials for industrialization and our daily life, but their influences on other aspects of life need to be taken into consideration. While the whole world benefits from mining's contributions, most of the resulting detrimental impacts on the environment and society fall on the local communities. The participation of the local community is one solution to decrease the risks from community-related problems. Subsequently, the requirements of mining sustainable development can be met. A literature review was conducted on mining sustainability and stakeholder participation, and the shortcomings of existing research and difficulties of further ...


Understanding The Connection Between Blasting And Highwall Stability, Robert Quentin Eades, Kyle A. Perry Jan 2019

Understanding The Connection Between Blasting And Highwall Stability, Robert Quentin Eades, Kyle A. Perry

Mining and Nuclear Engineering Faculty Research & Creative Works

Surface mines continue to implement highwalls for several reasons, such as increasing recovery, improving margins, and justifying higher stripping ratios. Highwall stability is a complex issue that is dependent upon a variety of mining and geologic factors, and a safe design is necessary for a successful surface operation. To improve highwall stability, it is important to understand the connection between local geology and blasting. Explosives are employed throughout the mining industry for primary rock breakage. There are a number of controlled blasting techniques that can be implemented to improve highwall stability. These include line drilling, smooth wall blasting, trim blasting ...


The Status Of The Local Community In Mining Sustainable Development Beyond The Triple Bottom Line, Sisi Que, Liang Wang, Kwame Awuah-Offei, Yao Chen, Wei Yang Jun 2018

The Status Of The Local Community In Mining Sustainable Development Beyond The Triple Bottom Line, Sisi Que, Liang Wang, Kwame Awuah-Offei, Yao Chen, Wei Yang

Mining and Nuclear Engineering Faculty Research & Creative Works

Mineral products provide essential fuels and raw materials for industrialization and our daily life, but their influences on other aspects of life need to be taken into consideration. While the whole world benefits from mining's contributions, most of the resulting detrimental impacts on the environment and society fall on the local communities. The participation of the local community is one solution to decrease the risks from community-related problems. Subsequently, the requirements of mining sustainable development can be met. A literature review was conducted on mining sustainability and stakeholder participation, and the shortcomings of existing research and difficulties of further ...


Implementing An Ore Reconciliation System Supported By Statistical Process Control, Bryan Nielson Apr 2018

Implementing An Ore Reconciliation System Supported By Statistical Process Control, Bryan Nielson

Graduate Theses & Non-Theses

There are several stages within mine planning that utilize different block models to help predict future values. Ore reconciliation manages the variance observed between the forecasted values from these block models and actual production data. This paper primarily focuses on an ore reconciliation system that was developed for an open pit copper operation located in the Western United States. A monthly reconciliation approach has been setup in a stepwise format along the mine value chain. Mine call factors are calculated each month for each step within the operation’s mining process to measure the variance between predicted values and production ...


The Effect Of Overloading On Reliability Of Wheel Loader Structural Components, Eric Raymond Achelpohl Jan 2018

The Effect Of Overloading On Reliability Of Wheel Loader Structural Components, Eric Raymond Achelpohl

Doctoral Dissertations

"This research attempts to provide a fundamental understanding into the relationship between the productivity of material handling equipment, specifically wheel loaders, and their ability to operate reliably when subjected to high overload conditions. The overall aim is to determine the effect of overloading the bucket on wheel loader reliability. The specific objectives of the research are to: 1) evaluate the effect of overloading the bucket on wheel loader productivity; 2) examine the effect of overloading the bucket on hydraulic pressures in the hoist cylinders (used as a proxy for forces on a wheel loader); and 3) investigate the effect of ...


Investigation Of Environmental Cadmium Sources In Eastern Kentucky, Elizabeth Maher Jan 2018

Investigation Of Environmental Cadmium Sources In Eastern Kentucky, Elizabeth Maher

Theses and Dissertations--Mining Engineering

Utilizing data collected by the University of Kentucky Lung Cancer Research Initiative (LCRI), this study investigated potential mining-related sources for the elevated levels of cadmium in Harlan and Letcher counties. Statistical analyses for this study were conducted utilizing SAS. A number of linear regression models and logarithmic models were used to evaluate the significance of the data. The linear regression models consisted of both simple and multivariate types, with the simple models seeking to establish significance between the potential sources and urine cadmium levels and the multivariate models seeking both to identify any statistically significant linear relationships between source types ...


Numerical Analysis Of Stress Distributions For Multiple Backfilled Stopes, Christopher Richard Newman Jan 2018

Numerical Analysis Of Stress Distributions For Multiple Backfilled Stopes, Christopher Richard Newman

Theses and Dissertations--Mining Engineering

Over the past three decades, technological innovations with respect to cemented paste backfill (CPB) as a means of ground support has allowed for increased production within the mining industry, management mine waste costs, as well as the improvement of the overall health and safety of underground mining operations. Despite the extensive use of this relatively new ground support material, many fundamental factors affecting the design of safe and economical CPB structures are still not well understood.Recently, a significant amount of academic and industry research has been conducted to better understanding the distribution of stress with respect to primary-secondary extraction ...


Improving Workers' Safety And Health In The Zimbabwean Mining And Quarrying Industry, Bernard Mabika Jan 2018

Improving Workers' Safety And Health In The Zimbabwean Mining And Quarrying Industry, Bernard Mabika

Walden Dissertations and Doctoral Studies

Lack of effective occupational safety and health (OSH) strategies is a reason that

workplace accidents in the mining and quarrying industry remain high, making the

industry one of the riskiest operations worldwide. The purpose of this multiple case study

was to explore successful strategies mining and quarrying leaders in Zimbabwe used to

improve OSH. The key research question addressed successful strategies leaders in the

mining and quarrying industry use to improve employee occupational safety and health in

Zimbabwe. Six successful business leaders from 3 mining and quarrying mines in

Zimbabwe demonstrated an exception to unsafe practices, particularly through their

exceptional ...


Comparing Distributed Acoustic Sensing To Three-Component Geophones In An Underground Mine, Nikolas Nesladek Jul 2017

Comparing Distributed Acoustic Sensing To Three-Component Geophones In An Underground Mine, Nikolas Nesladek

Graduate Theses & Non-Theses

Geophones have become the industry standard for seismic data collection. However, a relatively new method is gaining popularity called Distributed Acoustic Sensing (DAS). DAS uses changes in backscattered light of a fiber-optic cable to detect strain from acoustic energy. The purpose of this project was to make a direct comparison between DAS and three component geophones, specifically in a mining setting. Experiments were done in the Underground Education Mining Center on the campus of Montana Tech. The sources used for this project were vertical sledgehammer shots, oriented shear sledgehammer shots, and blasting caps set off in both unstemmed and stemmed ...


Responsiveness Of Mining Community Acceptance Model To Key Parameter Changes, Mark Kofi Boateng, Kwame Awuah-Offei Jun 2017

Responsiveness Of Mining Community Acceptance Model To Key Parameter Changes, Mark Kofi Boateng, Kwame Awuah-Offei

Mining and Nuclear Engineering Faculty Research & Creative Works

The mining industry has difficulties predicting changes in the level of community acceptance of its projects over time. These changes are due to changes in the society and individual perceptions around these mines as a result of the mines' environmental and social impacts. Agent-based modeling can be used to facilitate better understanding of how community acceptance changes with changing mine environmental impacts. This work investigates the sensitivity of an agent-based model (ABM) for predicting changes in community acceptance of a mining project due to information diffusion to key input parameters. Specifically, this study investigates the responsiveness of the ABM to ...


Electromagnetic Signal Feedback Control For Proximity Detection Systems, Adam K. Smith Jan 2017

Electromagnetic Signal Feedback Control For Proximity Detection Systems, Adam K. Smith

Dissertations, Master's Theses and Master's Reports

Coal is the most abundant fossil fuel in the United States and remains an essential source of energy. While more than half of coal production comes from surface mining, nearly twice as many workers are employed by underground operations.

One of the key pieces of equipment used in underground coal mining is the continuous mining machine. These large and powerful machines are operated in confined spaces by remote control. Since 1984, 40 mine workers in the U. S. have been killed when struck or pinned by a continuous mining machine. It is estimated that a majority of these accidents could ...


The Andacollo's Mining Community: Ethnographic Work-Based Approach To Corporate Social Responsibility Policies And Practices, Ubirata De Oliveira Jan 2017

The Andacollo's Mining Community: Ethnographic Work-Based Approach To Corporate Social Responsibility Policies And Practices, Ubirata De Oliveira

Walden Dissertations and Doctoral Studies

This ethnographic study was designed to explore the phenomenon of corporate social responsibility (CSR) in the mining industry. The research addressed the impacts of a problematic, systemic, and ethnocentric (top-down) CSR approach driven by a transnational mining company, and proposed a novel cultural relativist (bottom-up) CSR approach looking at the social needs of the community. Solving the problem stemming from the ethnocentric approach is important for both the mining company and the community affected by the CSR program, as it will alter dynamics between actors and mitigate social conflicts. The purpose of this study was to investigate factors that improve ...


Stochastic Modeling And Dem Simulation Of Granular Media Subsidence Due To Underground Activity, Rodrigo Borela Valente Aug 2016

Stochastic Modeling And Dem Simulation Of Granular Media Subsidence Due To Underground Activity, Rodrigo Borela Valente

Open Access Theses

Many communities around the world have been established in areas of ongoing, as well as ceased, underground mining activity. Ground movements induced by ore extraction methods and the collapse of abandoned cavities have long been recognized as a hazard to surface structures. A number of approaches have been proposed for the prediction of subsidence in underground mining regions, and their integration to Geographic Information Systems (GIS) can produce a powerful risk management tool. Nevertheless, this application is often limited by either a lack of generality or excessive computational cost of the methods available.

In this work, the stochastic subsidence model ...


Eliciting Drivers Of Community Perceptions Of Mining Projects Through Effective Community Engagement, Liang Wang, Kwame Awuah-Offei, Sisi Que, Wei Yang Jul 2016

Eliciting Drivers Of Community Perceptions Of Mining Projects Through Effective Community Engagement, Liang Wang, Kwame Awuah-Offei, Sisi Que, Wei Yang

Mining and Nuclear Engineering Faculty Research & Creative Works

Sustainable mining has received much attention in recent years as a consequence of the negative impacts of mining and public awareness. The aim of this paper is to provide mining companies guidance on improving the sustainability of their sites through effective community engagement based on recent advances in the literature. It begins with a review of the literature on sustainable development and its relationship to stakeholder engagement. It then uses the literature to determine the dominant factors that affect community perceptions of mining projects. These factors are classified into five categories: environmental, economic, social, governance and demographic factors. Then, we ...


A Life Cycle Assessment Of A Uranium Mine In Namibia, Janine Lambert Jun 2016

A Life Cycle Assessment Of A Uranium Mine In Namibia, Janine Lambert

Graduate Theses and Dissertations

Uranium mining and nuclear power is a controversial topic as of late, especially in light of the recent Fukushima event. Although the actual use of nuclear fuel has minimal environmental impact, its issues come at the very beginning and end of the fuel’s life cycle in both the mining and fuel disposal process. This paper focuses on a life cycle analysis (LCA) of uranium mine in the desert nation of Namibia in Southern Africa. The goal of this LCA is to evaluate the environmental effects of uranium mining. The LCA focuses on water and energy embodiment such that they ...


Bio-Physical Closure Criteria Without Reference Sites: Realistic Targets In Modified Rivers, Melanie L. Blanchette, Mark Lund, Robyn Stoney, Digby Short, Colm Harkin Jan 2016

Bio-Physical Closure Criteria Without Reference Sites: Realistic Targets In Modified Rivers, Melanie L. Blanchette, Mark Lund, Robyn Stoney, Digby Short, Colm Harkin

ECU Publications Post 2013

The use of reference sites for establishing closure criteria in areas disturbed by mining activities is common practice. ‘Reference’ sites are those considered to be largely unimpacted by anthropogenic activity (retaining desirable natural characteristics), and occurring near disturbed sites. Sites are considered rehabilitated when their biophysical condition approximates that of the reference site. However, this approach often creates impossible or unrealistic targets for miners seeking to close rehabilitated lands. For example, reference sites are often limited in availability (or non-existent) due to impacts by other land uses. Further, any available reference sites might not be realistic matches for the rehabilitated ...


Energy Efficiency And Carbon Dioxide Emissions Across Different Scales Of Iron Ore Mining Operations In Western Australia, Shanuka Dilhani Palamure Jan 2016

Energy Efficiency And Carbon Dioxide Emissions Across Different Scales Of Iron Ore Mining Operations In Western Australia, Shanuka Dilhani Palamure

Theses: Doctorates and Masters

During the last two decades, Western Australian iron ore mining industry experienced an exponential production growth arising from increased global demand for steel. The upturn in the iron ore price and considerably lower production cost encouraged extensive mining and consequently high-grade ore reserves were gradually depleted. Despite the energy-intensive nature of mining, high profitability motivated the mining companies to extract marginal-grade deposits with additional processing requirements, which increased energy consumption and ultimately increased the cost of iron ore production. This thesis sought to identify the energy efficiencies of open-cut iron ore mining operations, in terms of scale of operation as ...


Investing In Least Developed Countries: The Aynak Copper Mine Project, Roosevelt Barfield Jan 2016

Investing In Least Developed Countries: The Aynak Copper Mine Project, Roosevelt Barfield

Walden Dissertations and Doctoral Studies

The rise of market globalization creates challenges for business executives seeking to pursue foreign direct investment (FDI) in least developed countries (LDC), such as Afghanistan. Multinational corporate (MNC) executives need strategies that will improve the timely delivery of minerals for mining projects in LDCs. Guided by the force field analysis theory, the purpose of this holistic, single-case study was to explore the strategy that 5 MNC executives in Beijing, China, used to improve the timely delivery of minerals associated with the Aynak copper mine project in Afghanistan. Semistructured interviews were used to elicit detailed narratives from MNC executives about their ...


The Relative Effect Of Charge Dimensions On Elastic Vibration Attenuation And Blast-Induced Seismic Energy Concepts, Nathan Thomas Rouse Jan 2015

The Relative Effect Of Charge Dimensions On Elastic Vibration Attenuation And Blast-Induced Seismic Energy Concepts, Nathan Thomas Rouse

Doctoral Dissertations

"This dissertation focuses on expanding the blasting industry's current understanding of the effect of charge geometry on blast vibration attenuation. The work includes a multiple regression analysis of a sample population of signature hole blast vibration data. The regression analysis is used to identify the relative effect of the variables that affect blast vibrations at various distances from the charge. The study suggests that the most common vibration models used in the blasting industry do not use all of the statistically significant variables. Therefore, the models neglect to fully describe the relationship between the significant variables and the blast ...


Gravity And Magnetic Investigations Into Possible Economic Mineral Deposits Within The Northwest St. Francois Terrane, Southeastern Missouri, Brandon Todd Ives Jan 2015

Gravity And Magnetic Investigations Into Possible Economic Mineral Deposits Within The Northwest St. Francois Terrane, Southeastern Missouri, Brandon Todd Ives

MSU Graduate Theses

The exposed Precambrian St. Francois Mountains in southeast Missouri are a well-studied terrane of rhyolites, granites, and basaltic dikes, but much of the buried basement lithology west of the exposed region is still poorly delineated. The western St. Francois is host to large hydrothermal Pb-Zn and Fe-oxide ore deposits, some of which were located with previous geophysical investigations. The economic ore deposits specifically in the Pea Ridge Mine in Washington County contain known economic minerals and rare earth element deposits. In order to further investigate the Precambrian basement lithologies and the possible locations of additional economic ore deposits, a gravity ...


A Framework For Understanding The Public's Perspectives Of Mining Applied To The Kentucky Coal Industry, Joshua M. Hoffman Jan 2013

A Framework For Understanding The Public's Perspectives Of Mining Applied To The Kentucky Coal Industry, Joshua M. Hoffman

Theses and Dissertations--Mining Engineering

People’s perceptions of mining are heavily based on the media they consume and the messages therein. News outlets ordinarily report on mining only when there is an accident or environmental concern. When messages that the public is exposed to are negative, it is no wonder that there are negative perceptions about mining.

Current public relations campaigns on the behalf of specific companies or select sectors do exist; however, this is often a reactionary move in response to recent shifts in the socio-political environment. The details of these campaigns are often tied up in proprietary information or withheld by public ...


Fuzzy Controlled Hydraulic Excavator With Model Parameter Uncertainty, Ganesh Kothapalli, Mohammed Hassan Jan 2011

Fuzzy Controlled Hydraulic Excavator With Model Parameter Uncertainty, Ganesh Kothapalli, Mohammed Hassan

ECU Publications 2011

The hydraulic actuated excavator, being a non-linear mobile machine, encounters many uncertainties. There are uncertainties in the hydraulic system in addition to the uncertain nature of the load. The simulation results obtained in this study show that there is a need for intelligent control of such machines and in particular interval type-2 fuzzy controller is most suitable for minimizing the position error of a typical excavator’s bucket under load variations. We consider the model parameter uncertainties such as hydraulic fluid leakage and friction. These are uncertainties which also depend up on the temperature and alter bulk modulus and viscosity ...


Turbulent Flow Studies Of A Scaled Model Of A Large Mining Truck - Computations And Experiment, Wayne Randolph Sexton Apr 2010

Turbulent Flow Studies Of A Scaled Model Of A Large Mining Truck - Computations And Experiment, Wayne Randolph Sexton

Mechanical & Aerospace Engineering Theses & Dissertations

Modern mining operations are highly reliant on the amount of material that can be removed from the earth, transported to processing, and then processed. The companies that design and build mining dump trucks concentrate on improving the material payload capacity. Currently, the largest trucks are 400ton-class trucks. The design of these large mining dump trucks certainly does not stem from aerodynamics, but rather, from functionality and payload As a result, the shear size and asymmetric functional design creates interesting turbulent wakes on, around, and behind these trucks. This research focuses on the turbulent flow behind the truck. Computational Fluid Dynamic ...


Tree-Compatible Ground Covers For Reforestation And Erosion Control, Jennifer Franklin, James Burger, Victor Davis, Carl Zipper, Jeff Skousen, Chris Barton, Patrick Angel Jun 2009

Tree-Compatible Ground Covers For Reforestation And Erosion Control, Jennifer Franklin, James Burger, Victor Davis, Carl Zipper, Jeff Skousen, Chris Barton, Patrick Angel

Jennifer Franklin

Productive native forests create economic value for landowners, produce raw materials for wood-based products, and provide benefits such as watershed control, water quality protection, carbon storage, wildlife habitat, and native plant diversity. Owners of lands mined for coal in Appalachia are increasingly interested in assuring that productive forests are restored after mining.

Sediment control is essential to coal mine reclamation under the Surface Mining Control and Reclamation Act (SMCRA). Here, we describe how mining firms can achieve good tree survival and restore forest productivity by using tree-compatible ground covers, when necessary, to control erosion and meet ground cover standards.


Tree-Compatible Ground Covers For Reforestation And Erosion Control, James Burger, Victor Davis, Jennifer Franklin, Carl Zipper, Jeff Skousen, Chris Barton, Patrick Angel Jun 2009

Tree-Compatible Ground Covers For Reforestation And Erosion Control, James Burger, Victor Davis, Jennifer Franklin, Carl Zipper, Jeff Skousen, Chris Barton, Patrick Angel

Jennifer Franklin

Productive native forests create economic value for landowners, produce raw materials for wood-based products, and provide benefits such as watershed control, water quality protection, carbon storage, wildlife habitat, and native plant diversity. Owners of lands mined for coal in Appalachia are increasingly interested in assuring that productive forests are restored after mining.

Sediment control is essential to coal mine reclamation under the Surface Mining Control and Reclamation Act (SMCRA). Here, we describe how mining firms can achieve good tree survival and restore forest productivity by using tree-compatible ground covers, when necessary, to control erosion and meet ground cover standards.


Creating Lakes From Open Pit Mines: Processes And Considerations, Emphasis On Northern Environments, Christopher H. Gammons, Les N. Harris, James M. Castro, Peter A. Cott, Bruce W. Hanna Jan 2009

Creating Lakes From Open Pit Mines: Processes And Considerations, Emphasis On Northern Environments, Christopher H. Gammons, Les N. Harris, James M. Castro, Peter A. Cott, Bruce W. Hanna

Geological Engineering

Creating Lakes from Open Pit Mines: Processes and Considerations, Emphasis on Northern Environments. This document summarizes the literature of mining pit lakes (through 2007), with a particular focus on issues that are likely to be of special relevance to the creation and management of pit lakes in northern climates. Pit lakes are simply waterbodies formed by filling the open pit left upon the completion of mining operations with water. Like natural lakes, mining pit lakes display a huge diversity in each of these subject areas. However, pit lakes are young and therefore are typically in a non-equilibrium state with respect ...


Effect Of Water Ice Content On Excavatability Of Lunar Regolith, Leslie S. Gertsch, Robert Gustafson, Richard E. Gertsch Feb 2006

Effect Of Water Ice Content On Excavatability Of Lunar Regolith, Leslie S. Gertsch, Robert Gustafson, Richard E. Gertsch

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The amount of water ice contained within prepared samples of JSC-1 lunar regolith simulant strongly affects the excavatability of the material. As part of a NASA Phase I SBIR project, load-penetration testing of JSC-1 lunar regolith simulant was performed at water ice concentrations ranging from zero to 11% by mass (approximately saturated), after compaction and cooling to simulate probable lunar conditions. After mixing dry JSC-1 simulant with the appropriate amount of water, the samples were individually compressed into containment rings under 48 MPa of pressure. Thermocouples embedded in the samples monitored internal temperature while they were cooled in a bath ...


Subsidence Resulting From Multiple-Seam Longwall Mining In The Western United States - A Characterization Study, United States Department Of The Interior, Bureau Of Mines Jan 1991

Subsidence Resulting From Multiple-Seam Longwall Mining In The Western United States - A Characterization Study, United States Department Of The Interior, Bureau Of Mines

Mines and Mineral Resources

This report details the investigation of multiple-seam longwall subsidence conducted by the U.S. Bureau of Mines from 1978 to 1989. A field investigation monitored ground surface movements over four upper-seam longwall panels and six lower-seam panels. The characteristics of the subsidence occurring as a result of mining these panels are examined; in particular, the angle of draw, subsidence development, total magnitude and areal extent, and critical width are evaluated and discussed. Comparisons are also made between the characteristics of multiple-seam longwall subsidence and single-seam longwall subsidence that occurred at the same site.


A Knowledge-Based Expert System For Managing Underground Coal Mines In The U.S., H. Singh, S. Yuan, C. M. Watts, J. M. Dean, N. P. Reddy, R. S. Nutter Jr., R. Larry Grayson Jul 1990

A Knowledge-Based Expert System For Managing Underground Coal Mines In The U.S., H. Singh, S. Yuan, C. M. Watts, J. M. Dean, N. P. Reddy, R. S. Nutter Jr., R. Larry Grayson

Mining and Nuclear Engineering Faculty Research & Creative Works

The Mine Management Support System which is being developed as a knowledge-based expert system for better management of underground coal mines, is presented. Concentrating on capturing the complex body of knowledge needed to enhance efficient management of a mine, it will encompass information and preferred rules on work scheduling, work practices, regulations impinging on the accomplishment of work, responses to operating problems, and the labor-management work agreement. Different components of the mine system, modeled using an object-oriented layering technique, are displayed graphically to aid in coordinating work plans and to present locations of equipment, supplies, and proposed subsystem components.