· Despite the challenging lighting conditions and size of underground limestone mines that has previous hindered photogrammetric surveys in these environments, over 13,000 photographic images were
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Between 2015 and 2022, five massive pillar collapses occurred at four underground stone mines in the eastern USA. In three of the four mines, the collapses occurred in legacy workings that were at least 15 years old. The pil-lar collapse areas in all five of the case studies contained benched pillars that did not meet the S-Pillar criteria.
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· Rippers can be used for limestone mining as limestone is a ‘rippable’ sedimentary rock (refer to Sect. 3.1.1) Using rippers in small mines or for a group consisting of more than one mine is economical and productive. Instantaneous blasting or blasting with delay detonators in mines are executed in circuits.
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underground limestone quarries (mines) in two villages in Belgian South Limburg. During the last 350 years the formation of such as well as the causal factors of sinkholes. One hundred seventy
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This study examined musculoskeletal injury risk at four mining sites: underground coal, underground limestone, surface copper, and surface phosphate. Each site offered opportunities to investigate musculoskeletal disorder (MSD) injury risks and how those risks might be identified and categorized.
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· AI-enhanced description. Tacius Golding High. Over 70% of Jamaica's land is limestone, which is composed mainly of calcium carbonate. Limestone weathers through carbonation as rainwater mixes with carbon dioxide to form a weak acid that dissolves calcium carbonate. This process forms several distinctive karst landforms,
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Pillar stability continues to be a significant concern in multiple-level mining conditions, particularly for deep mines when pillars are not stacked or the thickness of interburden between mining levels is thin. The National Institute for Occupational Safety and Health (NIOSH) is currently conducting research to investigate the stability of pillars in multiple
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· 8 Different Types of Streams (Images + Interesting Facts) Limestone caves form due to the chemical weathering of limestone bedrock caused by natural acid present in groundwater and rainwater. As rain falls to the ground, it dissolves carbon dioxide in the air to form weak carbonic acid. This acidity causes solution or chemical weathering to
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· The safety factors at mid-pillar are lower than those along the back and floor line where the Esterhuizen G, Dolinar D, Ellenberger J, Prosser L, Iannacchione A. Roof stability issues in underground limestone
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:Limestone MinesUnderground Limestone MiningMining IndustryFive massive ground collapses have occurred in underground limestone mines in the United States between 2015 to 2021, with two of the collapses occurring at a single
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In this study, the stability of an underground mine was evaluated considering the hydro-mechanical characteristics of the rockmass. Recently, mining methods have changed
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· Abstract and Figures. The development of a multiple level underground mine is a complex task in which geology, engineering, ground control, and unit operations are integrated into a single mine
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In this study, the stability of an underground mine was evaluated considering the hydro-mechanical characteristics of the rockmass. Recently, mining methods have changed from open-pit mining to underground mining, which has led to an increase in environmental problems and civil complaints. The effects of rock engineering characteristics and
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Massive Department National Institute of Health. Pillar Collapses in Coal for Occupational Safety Human Services, Assessing pillar Outreach collapse Seminar, and airblast and Health. hazards in underground stone mines. C, Rumbaugh, Meeting, November 9, 2021. Presented at the Mt. Pleasant 41st Intl. G.
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:Limestone MinesUnderground Mines in The United States · From 2015 to 2021, five massive pillar collapses occurred at four underground stone mines in the eastern USA. These events resulted in powerful
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· This study is to predict the possible flooding area in an underground limestone mine, using the spatial analysis based on the Geographic Information Systems (GIS). Five key factors were selected
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· is conducting a monitoring program at the Pleasant Gap underground limestone mine in central A combination of these factors may lead to various degrees of multiple-seam mining interaction. In
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:Limestone MinesUnderground Stone Mines · The emphasis has been placed on the impact of the following limestone pillar stability parameters: pillar width-to-height (w/h) ratio, benching, the existence of
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19–37 Fig. 4. Pictures of quarries. (A) Entrance of an underground limestone quarry in a valley bottom (Heers, in 2004); (B and epicentres of recent earthquakes requires checking the influence of seismicity as a triggering factor of sinkhole formation
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· The National Institute for Occupational Safety and Health (NIOSH) has previously established pillar design guidelines for shallow, flat-lying mines and single-level operations. Little guidance exists for ground control design in multiple-level stone mines, and understanding the interactions between levels would allow engineers to better select
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· Properties of Limestone: Calcium Carbonate Content: Limestone is primarily composed of calcium carbonate (CaCO3), which gives it its fundamental chemical composition. Color: Limestone can
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· These underground wonders hold valuable insights into the Earth’s geological history and provide a glimpse into the intricate processes that shape our planet. In this article, we will delve into the formation process of limestone caves and explore the significance of understanding their origins.
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· Soluble rocks (mainly limestone) are widely distributed in China, with a distribution area of up to 3.65 million km 2, accounting for approximately one-third of the country’s land area.In
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Karst sinkholes are naturally enclosed funnel-shaped depressions that are the prime diagnostic features of a karst landscape (Figure 12.2.8). These features can range in size from a few meters in diameter up to a kilometer or so in size. In European literature karst sinkholes are typically called ‘dolines’.
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· The final form of the pillar strength equation for stone mines is as follows: (4) S = 0.65 × U C S × L D F × w 0.30 h 0.59 where UCS is the uniaxial compressive strength of the intact rock, LDF is the large discontinuity factor shown in Eq. (3), and w and h are the pillar width and height, respectively, in meters.
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· observations show that the collapse of underground limestone mines results from a nearly triple of the dry ones and that the factor of safety reduced from 1.74 in air -dry condition to 1.07 in
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· The design and strength of pillars are important parameters while implementing the room-and-pillar mining method in a limestone mine. The process becomes complex with the presence of the karst voids which are frequent phenomena in a carbonate rock formation. The karst system is a network of cavities that along with an
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The safety factor was also reduced because of the water-saturated condition from (1.74) in airdry (2006) Numerical modelling of the effect of weathering on the progressive failure of underground limestone mines, in: Van Cotthem, A., Charlier, R., Thimus, J.-F
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Massive pillar collapses in US underground limestone mines: 2015–2021 Rumbaugh, Gregory M.; Mark, Christopher ; Kostecki, Todd R (w/h) of 0.8 or less. This study elaborates on these factors and proposes a framework to
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Information Circular 9475 Ergonomic Assessment of Musculoskeletal Risk Factors at Four Mine Sites: Underground Coal, Surface Copper, Surface Phosphate, and Underground Limestone By William J. Wiehagen and Fred C. Turin U.S. DEPARTMENT OF HEALTH
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