Mining Engineering Commons^™

The Impact Of A Strong Local Supply Chain On Regional Economic Impacts Of Mining, Meiyu Xing

Masters Theses

"With growing social conflicts due to social and environmental concerns mines need to be able to create shared value for all stakeholder in their quest to promote sustainable development. Given the sensitivity of a mine's regional economy contribution to its supply chains, any improvement in supply chains strategy will be beneficial for mines and their stakeholders. The objectives of this work were to: (i) test the hypothesis that supply chain management strategy, by mines in a region, significantly affects regional economy; and (ii) develop a methodology to identify the critical backward commodities of a regional mining sector.

Valid methods have …

Determining And Mitigating The Effects Of Firing A Linear Shaped Charge Under Water, Brian Burch

Masters Theses

"When fired under water, a Linear Shaped Charge (LSC) does not penetrate a steel target as well as in air. This lack of performance has been a problem for shaped charge manufacturers and their clients. It was obvious that this degradation of performance is due to water having a higher density than air and water being incompressible compared to air. This study aimed to better determine how the water was affecting the LSC and to provide a method of mitigation.

LSCs of different sizes were submerged under water and fired through the water with and without a target. It was …

Test Development To Determine The Feasibility Of Rubber Tractor Treads For Use As Blasting Mats, Matthew Kurtis Coy

Masters Theses

"The objective of this thesis was to determine if rubber tractor treads could be used as an alternative material for blasting mats. These treads are made from steel cable and vulcanized rubber and are very tough. However, once they reach the end of their life on mobile equipment, they are destined for a landfill, or dump site because they are too tough to recycle. A potential alternative use for them is as blasting mats.

An examination of existing mat designs was conducted to better understand the matting methods used by the blasting industry today, to learn from those designs allow …

An Analysis Of Burn Cut Pull Optimization Through Varying Relief Hole Depths, Michael Robert Allen

Masters Theses

"In underground blasting, the pull of the initial cut is the limiting factor for the success of the rest of the round. By improving the pull of the first cut, a critical step is made towards improving the entire round. This project attempted to optimize a burn cut's effective pull by varying the depths of the relief holes in the burn, and then analyzing the results. In testing, relief holes were drilled to depths both shorter and longer than that of the cut's charged holes. The overall objective was to consistently achieve greater pull than in a standard burn, using …

Analysis Of A Ventilation Network In A Multiple Fans Limestone Mine, Ali Haghighat

Masters Theses

"As mining progresses the total resistance of an excavation is increased, the mine characteristic curve becomes steeper, and the operating point moves up the fan curve, reducing the total air quantity and increasing the system pressure. For multi-level ventilation networks with a number of fans the process can be tedious, and on a count of numerous dependent factors the optimal combination of fans is very hard to be achieved. The design of a ventilation network in conjunction with multi surface fans and booster fans entails a complex procedure.

The objective of this study is to provide a plan to improve …

The Effects Of Advanced Structural Materials To Mitigate Explosive And Impact Threats, Caleb Michael Baumgart

Masters Theses

"In a world of ever newer and modified improvised explosive devices (IEDs) that are very common in certain parts of the world, it is always more important to improve the devices used for protection. This research endeavors to design and analyze a blast barrier using three different media types to mitigate the high pressures from an IED or a car bomb. The three media types used in this research are pumice, steel grit, and foam. Six barriers were built to test the three media types and account for the changes from a standard solid concrete barrier to a barrier with …

Behavior In Air Leakage And Recirculation Under The Influence Of Booster Fans, Koziba Feledi

Masters Theses

"A booster fan is an underground mechanical ventilation equipment installed in series with a main surface fan that is used to boost the air pressure provided by the surface main fan passing through it. As mining continues to expand and go deeper, the need for improved and efficient ventilation increases. This has led to the use of booster fans and other auxiliary ventilation devices in underground mines. Research defining how system leakage and recirculation are affected by booster fans; describing how system leakage and recirculation are affected by the location, placement, and amount of air pressure from the booster fans; …

A Modified Initiation And Cut Profile Study Of The 10500 Grain Per Foot Linear Shaped Charge, Matthew Ortel

Masters Theses

"A 10,500 grain per foot (gr/ft.) linear shaped charge (LSC) was developed to cut targets that were too thick for smaller LSC. The manufacturer observed shallower penetration from the 10,500 gr/ft. LSC than was expected. This prompted investigations to uncover the cause of the perceived reduced performance.

A study performed at the Missouri University of Science and Technology changed the initiation method of the 10,500 gr/ft. charge to increase the cut performance of the charge. A modified two point, single end initiation method was devised and tested. This initiation method was termed "dual initiation" and focused on creating a planar …

Utilization Of Booster Fans In Underground Mines, Arash Habibi Javanbakht

Masters Theses

"Booster fans are large underground fans that can increase the volumetric efficiency of ventilation systems by balancing the pressure and quantity distribution throughout a mine, reducing leakage and reducing the total power requirement. The objective of this study is to provide potential users of booster fans with the necessary information on the design, installation and operation of main underground fans. The guidelines listed in this paper were formulated based on current U.S. and international standards, safe operating practices developed by the mining industry, and recommendations provided by fan manufacturers. The principles involved in the design and installation of booster fans …

Methods For Evaluating Effect Of Operators On Drag Line Energy Efficiency, Maryam Abdi Oskouei

Masters Theses

"Draglines are dominant machines and the most significant electricity consumers in surface coal mines. With the growing price of energy, environmental concerns, and the high sensitivity of mine profitability to dragline productivity, any improvement in efficiency of dragline will be beneficial for mines. Research has shown that operator practices have a significant impact on energy efficiency of mining loading tools. However, not enough work has been done to provide guidance on how to quantitatively assess the effect of operator practices on dragline energy efficiency.

The objectives of this work were to: (i) test the hypothesis that dragline operator's practices and …

Stochastic-Optimization Of Equipment Productivity In Multi-Seam Formations, Elijah Adadzi

Masters Theses

"Short and long range planning and execution for multi-seam coal formations (MSFs) are challenging with complex extraction mechanisms. Stripping equipment selection and scheduling are functions of the physical dynamics of the mine and the operational mechanisms of its components, thus its productivity is dependent on these parameters. Previous research studies did not incorporate quantitative relationships between equipment productivities and extraction dynamics in MSFs. The intrinsic variability of excavation and spoiling dynamics must also form part of existing models. This research formulates quantitative relationships of equipment productivities using Branch-and-Bound algorithms and Lagrange Parameterization approaches. The stochastic processes are resolved via Monte …

Effects Of Coal Comminution In Relation To Waterjet And Selected Feed Properties, Yaqing Li

Masters Theses

"The necessity to develop a viable alternative to oil means that the development of coal-water fuels (CWF) has become increasingly important. However, the existing methods of comminution to prepare ultrafine particles for CWF are very inefficient. Consequently, a number of novel methods of comminution have been investigated in order to increase the efficiency of the process.

In this research, a new method of comminution using a high-pressure waterjet has been tested to produce ultrafine particle sizes necessary for efficient CWF process. To establish the fundamental performance of the waterjet mill, the influence of the operational pressure, standoff distance, feed size, …

Finite Element Analysis Of Blade-Formation Interactions In Excavation, Osei Brown

Masters Theses

"The efficiency and costs of mining operations greatly depend on the efficient design and use of excavators. The performance of these capital-intensive excavators requires thorough understanding of the physical and design factors that affect the formation-cutting tool interaction process. The current body of knowledge, based on experimental and analytical methods, provides limited understanding of these factors, which limits the accurate design and performance of excavators. The soil constitutive equations used in most of the available finite element (FE) models also fail to adequately capture the elastic and plastic behaviors of soil formations. This research initiative uses FE techniques to model …

The Effects Of Water On Sympathetic Detonation And Dead Pressing Of Dynamite And Emulsions, Adam Michael Doerfler

Masters Theses

Dynamite and emulsions are very effective explosives in blasting; however they do have some shortcomings. Dynamite is prone to sympathetic detonation whereas emulsions are prone to dead pressing. While this does not happen all the time, the conditions in which the explosives are used do have an effect on whether or not they will sympathetically detonate or dead press.

Numerous researchers have investigated sympathetic detonation for a relationship between the distance between charges, hole separation distance, and size of explosive. This research aimed to look at how hole separation distance was affected when water was introduced into the boreholes for …

Pressed Powdered Titanium And Aluminum Conical Shaped Charge Penetration Of Geological Targets, Dominique John Nolan

Masters Theses

"Conical Shaped Charge penetration into rock is dependent on the physical characteristics of the rock itself and the design and composition of the shaped charge conducting the work. This study looks at the effects of a non-typical conical shaped charge and its penetration into four different rock targets. The shaped charge is made of a liner, which is not a typical solid but instead is a pressed powdered metallic compound of Titanium (Ti) and Aluminum (AI).

The study presents the raw data from testing against rock targets that range in density, uniaxial compressive strength (UCS), tensile strength, hardness scales, and …

Impact Effects Of Explosively Formed Projectiles On Normal And High Strength Concrete, Laurin Ashley Bookout

Masters Theses

"The ability to quickly estimate the damage that a projectile will do to a structure is highly desired for structures that will be required to resist threats of this nature. There are several formulas for concrete penetration due to projectile impact that are based on empirical data. However, there is a lack of publicly available data for projectile impacts with striking velocities that exceed 1 km/s and have weights greater than a few grams. This research is intended to expand the available data on explosively formed projectile impacts and determine which, if any, of the existing equations can be used …

Characterizing Formation Dredgeability For Clamshell Dredge, Bismark Osei

Masters Theses

"The lack of metrics to assess clamshell dredge formation dredgeability limits the ability of engineers to predict the dredgeability of compact material and increases the risks associated with clamshell selection. Research is, therefore, necessary to increase our understanding of clamshell dredgeability assessment by evaluating possible metrics that will allow the operator to select the optimal clamshell for the operation. Work done and motor energy are possible dredgeability metrics that can be estimated using micro-processor based machine monitoring. The objective of this work is to test the hypotheses that: (i) work done by the pistons during dredging, by a hydraulically actuated …

The Effects Select Physical Parameters Have On An Explosively Formed Projectile's Performance, Phillip R. Mulligan

Masters Theses

"Identifying how changes in the physical parameters of an Explosively Formed Projectile (EFP) affect its performance is crucial in determining what physical parameters could be changed to achieve a desired performance. This research analyzes five of the physical parameters of an EFP, similar to an Iranian design (Worsey, 2009), and the effects on performance. The five physical parameters selected for this research were charge weight, confining geometry, flyer thickness, flyer curvature, and explosives-type. Eighteen different EFP designs were used to test the penetration, measured velocity, production of a dominant projectile, and kinetic energy of these five physical parameters. Of the …

The Mitigation Effects Of A Barrier Wall On Blast Wave Pressures, Nathan Thomas Rouse

Masters Theses

"The study examined the mitigating effects of a blast barrier wall. This area of blast mitigation is of interest due to the many different applications involved in protecting a specific target from an explosive attack. The research follows a 1:50 scale layout using 73 gram, hemisphere-shaped, Composition-4 charges detonated at combinations of three standoff distances from a blast barrier wall set at three different heights. This project used 45 data points for each combination of standoff distance and wall height. This project expanded prior research conducted by the United States Army Corps of Engineers (USACE) by increasing the database of …

Application Of Life Cycle Assessment To Estimate Environmental Impacts Of Surface Coal Mining, Ofentse Ditsele

Masters Theses

"Coal plays an important role in meeting the energy needs of the World. Given its abundance and low cost, its use is bound to increase with the growing energy demand. Despite its importance, there are concerns over coal's environmental burdens. In order to extract and use coal in a sustainable manner, sustainability assessment has to be comprehensive. Life Cycle Assessment (LCA) provides systematic and quantifiable measures for assessing environmental burdens of products and processes. Extensive LCA work has been done on coal use, particularly in electricity generation, but, the coal mining stage has been neglected, for the most part. This …

Explosives Recognition And Awareness Training: A Psychological Approach To Pre-Blast Mitigation, James Wade Hawkins

Masters Theses

"The nation's security strategy tends to be reactionary to a specific event. It is rare when established policies have proven successful, even though there is substantial financial and resource investment. The payoff is measured by analyzing the desired minimal effect rather than prevention of the event altogether. Such is the case in combating explosives-related threats. Today, research and development, science and technology, are plugged as the saviors of a post-blast event. Synthetic and composite materials are used to strengthen barriers and cutting-edge technology is utilized to refine the latest in standoff detection. These legitimate measures provide a sense of security …

Measuring Blast Induced Rock Damage From Pre-Splitting Sandstone By Applying The Multichannel Analysis Of Surface Waves Geophysical Method, Charles Bradford Zdazinsky

Masters Theses

"Many blasting applications in the mining industry demand that the hard rock being blasted remains structurally competent. For example, pre-splitting is a common technique to reduce fracturing, and operators of dimension stone quarries use this blasting method to eliminate overbreak. When pre-split design parameters are not applied correctly, there will be a redistribution of stresses within the rock, resulting in Blast Induced Rock Damage (BID). Advances in geophysical technology are enabling blast technicians to monitor BID and then use the results to correctly design their blasts. The Multichannel Analysis of Surface Waves (MASW) geophysical method is new technology that is …

Novel Concepts For Monitoring The Stability Of Open Pit Mine Highwalls Using Radar Interferometry And Spectral Imaging, Jami Girard Dwyer

Masters Theses

"Ground control problems at surface mining operations can occur for a variety of reasons. The geologic setting, rock strengths, joint spacing, orientation, pore pressures, and many other factors contribute to slope instabilities that range from small rock falls to massive slides of material. While much of this ground movement can be predicted or controlled, each year many completely unexpected failures occur. This poses serious safety and economic issues for the mining industry, since any unanticipated movement of the ground increases the potential for significant property damage, injuries, and even death. In the United States alone, 70 people died in slope …

Stemming Technique For Loading Angled Holes Charged With Anfo, Michael David Wilkins

Masters Theses

"Little research has been published on stemming blast holes, particularly what happens during the process. Previous work has concentrated on the performance of the inert material to find the best way to seal the hole and retain the explosive energy, at the exclusion of determining what happens during the loading and stemming process. Such studies were carried out by Konya and Worsey.

The major problem with stemming studies is that rock is an opaque material, and the actual mechanisms involved during the stemming process cannot be viewed. For this reason, tests were performed using clear tubes to simulate a blast …

Experimental Investigation Of The Effect Of Geological Discontinuity Conditions Of Rock Splitting By Blasting, Shijie Qu

Masters Theses

"A series of modal scale, two borehole splitting test blasts was geometrically designed both with concrete and with Plexiglas. The discontinuities were all symetrically located midway between split holes and were oriented perpendicular to the desired split plane. Sand and clay filled discontinuities of 1/16, 1/8 and 1/4 inch width, and closed discontinuities were used. Both discontinuity frequency and width generally reduced the maximum successful split-hole spacing. The regularity and integrity of the split profile became poorer as the discontinuities were closer to the boreholes and the discontinuity width became greater, due to the cratering effect which occurred from the …

A Study On Fragmentation And Ground Vibration With Air Space In The Blasthole, Everett Ellsworth Bleakney Iii

Masters Theses

"The degree of fragmentation and the level of ground vibration from a bench blast employing standard full-column completely-coupled explosive charges are commonly controlled by varying one or more of the many dimensional variables of blast design. Blasting techniques such as decoupling and air-gapping, utilizing air space in the blasthole, have also been reported as having the potential to control rock fragmentation and ground vibration.

This investigation, using reduced-scale in situ bench blasts, examined the degree of fragmentation and the level of ground vibrations produced from the standard full-column completely-coupled, air-gapped, and decoupled methods of blasting to:

1. Compare the effectiveness …

Control Of Rock Fragmentation Through Explosive Coupling, Timothy Wayne Warden

Masters Theses

"Both detonation pressure and borehole pressure, resulting from an explosion within blastholes in rock, perform specific functions in the fragmentation of the rock and the generation of ground vibrations. The results of previous investigations would suggest that control of these pressures in the borehole would, to some extent, control the size distribution of the blasted particles. One method of influencing detonation and borehole pressures is by varying the hole diameter in relation to a constant charge diameter, called decoupling, and by varying the medium between the explosive charge and the rock.

This investigation examined the effects of geometric coupling, which …

Analysis Of The Stresses Induced In Rock By Rock Splitters., Diogenes De Jesus Chollett

Masters Theses

"The method of solution of the problem of determining the stress and displacement distributions around an unfractured circular hole subjected to nonuniform applied internal pressure located in an infinite plate is developed. Two problems are solved for two different representative boundary conditions. The problem of determining the stress distribution around a circular hole with two symmetric radial cracks subjected to nonuniform applied radial pressure located in an infinite plate is analyzed and developed for further solution"-- Abstract, p. ii

Creep And Stiffness Of Full Column Resin Grouted Roof Bolts., Wesley Clare Patrick

Masters Theses

"A three-phase test program was utilized to evaluate some creep and stiffness parameters of several types of full-column resin-grouted roof-bolt installations. The tests indicate that: (1) a large percentage of an applied load bleeds off during the first 100 hours subsequent to bolt installation; (2) the amount of load bleed-off is a f unction of the grout annulus size and the bolt surface roughness; (3) retightening of grouted rock bolts reduces the magnitude and rate of the load bleed-off phenomenon; and (4) resin-grouted roof bolts provide a stiffer roof support system in that bolt elongation resulting from an applied load, …

Decoupled Explosive Charge Effects On Blasting Performance, Roberto Ucar

Masters Theses

"This investigation was performed to determine the burden at which hard rock would break utilizing decoupled and unstemmed charges when the free surface parallel to the borehole was the wall of an open hole. This open hole was created by burn cuts and by drilling holes of 7-7/8 in. and 12 in. diameter. Additional tests were performed using partially stemmed charges where the stemming was the same size as the explosive charge.

The explosive used was a 0.75 lb. slurry charge, 1.5 in. diameter and 10 in. long. The diameter and depth of the borehole were 2 in. and …