Mining Engineering Commons^™

The Effect Of Natural Fractures On The Mechanical Behavior Of Limestone Pillars: A Synthetic Rock Mass Approach Application, Mustafa Can Süner

Graduate Theses, Dissertations, and Problem Reports (ETD)

In general, underground limestone mines have inherently strong rock and experience good ground stability. Also, modern pillar design guidelines developed by National Institute for Occupational Safety and Health (NIOSH) have improved the design of stable layouts for modern limestone mines. However, ground control-related incidents are still an important problem. In underground limestone mines, previously mined sections stay open for the life of the mine which may be many years, and it is possible for travel ways to working faces to pass through these old sections. In a recent massive pillar collapse in an old section of a mine in Pennsylvania …

An Interactive Mobile Equipment Task-Training With Virtual Reality, Lazar Zujovic

Graduate Theses, Dissertations, and Problem Reports (ETD)

Improving the quality of equipment training for the Heavy Equipment Operators (HEO) is a critical task in the ever-lasting effort to improve safety and eliminate equipment-related injuries in mining environments. Traditional miner training includes the use of hardcopy documents and video instructions. However, modern mobile and computer technology offers tremendous potential to improve the training process. One major responsibility for the heavy-machine operators is proper machine inspection. Establishing new training methods that utilize modern technologies—such as 360-degree images, videos, and Virtual Reality—and implementing computers for training purposes have a potential to help new operators learn how to conduct proper machine …

Adaptation Of Coal Mine Floor Rating (Cmfr) To Eastern U.S. Coal Mines, Sena Cicek

Graduate Theses, Dissertations, and Problem Reports (ETD)

Floor heave—the excessive deformation and failure of floor strata—is a serious problem for many underground coal mining operations in the U.S. There is an accepted floor heave design methodology developed for the Illinois basin coal mines (Gadde, 2009). However, for Eastern U.S. coal mines in the Appalachian region, there is not any systematic design method to assess floor heave potential. In order to prevent stability problems associated with floor failure and to ensure the safety of the miners in this region, a systematic and proactive method to assess the potential of floor stability that also takes the floor failure mechanisms …

Design And Development Of A Multi-Nodal Methane Detection System For Longwall Coal Mining, Amber P. Barr

Graduate Theses, Dissertations, and Problem Reports (ETD)

Methane (CH4) explosions pose significant dangers in longwall mining that may lead to injuries and fatalities. Safety is improved through diligent monitoring of CH4 concentration. Currently, regulations require a CH4 monitor be placed on the shearer, downwind of the cutting head. Portable monitor measurements must be taken at various times and locations. If any CH4 monitor measures a concentration greater than 1%, a warning signal must be given. Based on previous research and the location of the CH4 monitor mounted on the shearer (closest monitor to the face), if 1% methane is measured, the concentration at the face may be …

The Influence Of Spatial Variance On Rock Strength And Mechanism Of Failure, Danqing Gao

Graduate Theses, Dissertations, and Problem Reports (ETD)

The heterogeneity in the rock formation affects both rock behavior and the strength. The effect of heterogeneity is observed both at the laboratory scale and at the rockmass level. The mechanical properties of intact rock vary considerably at laboratory scale and often an average value is used for design purposes. Similarly, the values are arbitrarily scaled when used at rockmass level. In underground coal mines, the effect of variability of properties is often observed with the erratic roof failure events that occur throughout the mine. The approach often was to use the deterministic values from limited site data to estimate …

Upstream Tailings Dam - Liquefaction, Mladen Dragic

Graduate Theses, Dissertations, and Problem Reports (ETD)

The collapse of Dam I, tailings dam, at Vale S.A.’s (“Vale”) of the Córrego do Feijão Iron Ore Mine in Brazil was an accident that caused over 270 casualties and made irreparable damage to the surrounding environment. The exact reason for the failure is not known however, liquefaction was suspected to be the most influencing factor in the failure. Liquefaction failure of impoundment is increasing concern in the mining community and especially mine planners who will have to design and build the tailings dam. Different design methods are available with varied degree of challenges. Upstream construction methods, as one of …

Solution Tool To Predict Filter Cake Formation For Acid Mine Drainage (Amd) Slurries, Roberto Ecuador Martinez Ochoa

Graduate Theses, Dissertations, and Problem Reports (ETD)

Acid Mine Drainage (AMD), also known as alkaline mine drainage resulted from abandoned and active coal mining areas has been a major water pollutant in the mid-Atlantic region of the United States affecting aquatic life, recreational areas, tourism, etc. AMD results from during and post mining activities all around the US and the world containing high levels of acidic materials such as sulfate and other heavy metals.

The United States Environmental Protecting Agency (EPA) has recommended the use of different mechanisms for mitigation purposes due to considerable existing and potential damage generated by AMD. This report focuses on the usage …

Development, Analysis And Case Studies Of Impact Resistant Steel Sets For Underground Roof Fall Rehabilitation, Dakota D. Faulkner

Graduate Theses, Dissertations, and Problem Reports (ETD)

Underground mines often experience roof falls in entries, crosscuts, and intersections of active mining sections, main travel ways, and belt entries. Roof fall heights greater than 20 ft (6 m) make re-bolting of the newly exposed roof dangerous and impractical. To protect mine personnel, belts, moving vehicles, and other equipment, mine operators typically install steel structures such as square or arch sets in the roof fall areas. Wood lagging is usually installed between the steel-sets to enclose the area and protect the entry from recurring falls. Usually the void space above the steel-sets and wood lagging is backfilled. However, backfilling …

Fundamental Studies On The Recovery Of Rare Earth Elements From Acid Mine Drainage, Xue Huang

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Rare Earth Elements (REEs) are a group of 17 chemically similar elements that are essential raw materials for modern society. Given their increasing importance in civil and defense applications, many national governments, including the US, have denoted the REEs as critical materials and emphasized the need to identify and develop both conventional and unconventional resources to meet the growing demand. To address this challenge, the US Department of Energy has recently spearheaded efforts to evaluate the technical and economic feasibility of recovering REEs from coal and coal byproducts, which have been shown to contain REEs at an elevated concentration …

Solutions To Some Mine Subsidence Research Challenges, Jian Yang

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this work is to address three challenging topics, (1) effects of overburden key strata on subsurface subsidence; (2) effects of longwall subsidence on interstate highways and highway bridges; and (3) effects of dewatering mine water on surface subsidence over inactive room-and-pillar mines, in mine subsidence and to continue improvement of mine safety and health by reducing mine-subsidence related hazards.

Surface and subsurface subsidence events induced by underground mining activities are often capable of causing significant disturbances not only to surface structures, but also to subsurface structures. In this work, models and techniques to study three challenging topics …

Rational Drilling Control Parameters To Reduce Respirable Dust During Roof Bolting Operations, Hua Jiang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Roof bolting has been the primary means to improve mine safety in the aspect of preventing different types of roof falls in underground mines. However, based on the published researches, underground roof bolting operators exhibit a continued risk for overexposure to high levels of respirable coal and crystalline silica dust from the roof drilling operation. Inhaling these dust can cause coal workers’ pneumoconiosis (CWP), also known as black lung. Another job-related lung disease silicosis, a disabling and even fatal and irreversible illness, could be developed through overexposure to quartz-laden dust. A recent NIOSH research shows that the quartz content in …

A Critical Assessment On The Resources And Extraction Of Rare Earth Elements From Acid Mine Drainage, Christopher R. Vass

Graduate Theses, Dissertations, and Problem Reports (ETD)

Rare earth elements (REEs) are crucial to many modern products used in both civilian and defense applications. Currently, a reliable supply of these elements is uncertain with the clear majority of REE production and refining occurring predominately in China. Furthermore, domestic ore deposits with commercially attractive concentrations of REEs are uncommon in the United States. As a result, the identification of a domestic supply of these technology metals is essential not only for manufacturing consumer merchandise but also for national security. Recently, one promising source of REEs has been identified: coal and coal-byproducts. One of those is acid mine drainage …

Time-Dependent Deformation And Associated Failure Of Roof In Underground Mines, Yuting Xue

Graduate Theses, Dissertations, and Problem Reports (ETD)

In underground coal mines, roof falls are a major contributor to injuries and fatalities. Studies have related the occurrence of roof fall to weak immediate roof, high horizontal stress, entry orientation, etc. An often-neglected factor in studies on this topic has been the influence of time-dependent behavior of the roof rock on roof falls. The time-dependent roof failure activity involves both intact and failed rocks. Numerical simulation techniques are available that include time-dependent behavior; however, they lack constitutive models that consider both the intact and the failed behavior of rock. In addition, input properties for the creep models only include …

Fundamental Mechanism Of Time Dependent Failure In Shale, Neel Gupta

Graduate Theses, Dissertations, and Problem Reports (ETD)

In underground coal mines, mining activity disturbs the natural equilibrium state of in-situ stresses. The induced and in-situ stresses deform the rockmass surrounding the mine openings. Primary roof supports impede the deformation of the rockmass overlying the entries. However, failure can occur in the bolted rockmass, causing fatalities and injuries. The rockmass failure is erratic, and its occurrence often varies from a few days to months and years after the opening of the entry. One of the often-neglected factors in this process is the effect of time on the stability of mine openings, which can often be observed in the …

Shale Characterization And Size-Effect Study Using Scanning Electron Microscopy And X-Ray Diffraction, Debashis Das

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ground failure is a major contributor of the total fatalities in underground mines in the US. Underground coal mines in the Northern Appalachian region have weak roof rock mainly composed of shale and sandstone. Characterization of shale is indispensable for developing an effective ground control plan. However, this has not been done extensively. This thesis attempts to address this issue. It investigates the variation in mechanical properties of shale with variation in size. In addition, an attempt has been made to relate the strength of shale with its petrographic parameters. X-ray diffraction technique was used to estimate the compositional parameters …

Hydrogeology And Water Management In The Arkwright Underground Coal Mine, Pittsburgh Seam, Northern West Virginia, Bryant D. Mountjoy

Graduate Theses, Dissertations, and Problem Reports (ETD)

Arkwright #1 is a closed underground mine in the Pittsburgh coal seam near Morgantown, West Virginia USA. Arkwright shares perimeter boundaries/barriers with three other closed Pittsburgh seam mines (Osage #3, Jordan #93, Federal #1) and is partially overlain by flooded Sewickley seam mines, 25 m above it. This mine is significant primarily because it manages and treats water diverted from nearly 20 other closed mines over a 600 square kilometer area. This study examines water levels, pump records, and mine maps to describe the hydrogeology of Arkwright Mine. After closure in 1995, Arkwright and the adjacent northern Osage mines began …

Parametric Study Of Coal Liberation Behavior Using Silica Grinding Media, Adewale Wasiu Adeniji

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study evaluates the coal liberation behavior using silica as the grinding media by assessing the effects of four operating factors including nominal feed size, media size, shaft speed and grinding time, each of three levels on two response variables, the product P₈₀ and the specific energy. The coal material used in this study was mixed-phase particles commonly referred to as middlings, sampled from dense medium circuit at the Leatherwood preparation plant in Kentucky. One-third fractional factorial design of resolution III was implemented. Since silica was obtained in three standard size ranges as per manufacturer’s design, media size was …

Stability Analysis Of Bleeder Entries In Underground Coal Mines Using The Displacement-Discontinuity And Finite-Difference Programs, Xu Tang

Graduate Theses, Dissertations, and Problem Reports (ETD)

The stability of bleeder entries is essential for both mine ventilation and personnel travelling through the entries. Therefore, it is imperative that bleeder pillars remain stable and bleeder entries safe during their service life. Surprisingly, there are few published investigations on ground control issues in the bleeder entries. This thesis is an attempt to analyze the ground control problems in bleeder entries especially, the structural integrity of the bleeder entry. Two numerical programs (a) displacement discontinuity program-LaModel and (b) the finite difference program-FLAC were used to investigate these problems. Modeling results from the LaModel program indicated that the vertical stresses …

Coupling Numerical Simulation And Pattern Recognition To Model Production And Evaluate Carbon Dioxide Injection In Shale Gas Reservoir, Amirmasoud Kalantari-Dahaghi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Massive multi-cluster, multi-stage hydraulic fractures have significantly increased the complexity of the flow behavior in shale. This has translated into multiple challenges in the modeling of production from shale wells.

Most commonly used numerical techniques for modeling production from shale wells are Explicit Hydraulic Fracture (EHF) and Stimulated Reservoir Volume (SRV). Model setup for the EHF technique is long and laborious and its implementation is computationally expensive, such that it becomes impractical to model beyond a single pad. On the other hand, identifying the extent and conductivity of SRV is a challenging proposition. SRV technique is commonly used to simplify …