The mine backfill design ensures the integrity of the mine's crown pillar in preventing the potential for long-term subsidence. Kennecott officials said Stone is a mining and geotechnical engineer with more than 30 years experience. His primary expertise is in mining rock mechanics, and he is an internationally recognized expert in mine ...
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The Santo Niño ore body at Pinos Altos Mine has been in production since 2009 using both open pit and underground mining methods. Between 2015 and 2017, an extensive study evaluated extraction strategy of the Santo Niño crown pillar. The Agnico Eagle project team evaluated geomechanical, operational, safety and economical risks …
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A crown pillar is to be designed in the transition region from surface to underground operations. Crown pillar dimensioning effects the overall ore recovery in such small-scale ore bodies. Proper dimensioning has to ensure the stability of open pit mine slopes and underground mine structural units as underground mining progresses to …
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The maximum subsidence of the crown pillar is relatively small, because the mining stopes are fully filled after excavation at the subsea gold mine in the numerical model. The relative deformation rate (δ) of the crown pillar after the fifth mining stage is (11) δ = 18 / (55 × 1000) ≈ 0.033 % < 0.1 % Download : Download full-size image ...
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The Sanshandao Gold Mine is located on a seabed, and the crown pillar is the main barrier to isolating seawater and preventing it from entering the mine. The thickness of the crown pillar and the size of the point pillars have a substantial impact on the reduction of resource waste and the economic development of the mine. Therefore, …
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The profitability of a room and pillar mine depends on optimization of the size and spacing of the pillars so that the greatest portion of coal can be removed without compromising the stability of the pillars. ... This is repeated for successively high sub-levels extending the stope upward until the crown pillar is reached. The mine ore is mac ...
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Crown pillar dimensioning effects the overall ore recovery in such small-scale ore bodies. Proper dimensioning has to ensure the stability of open pit mine slopes …
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1. Introduction. A crown pillar is defined as the in-situ rock or transition region between the pit bottom and an underground opening due to a transition from open pit to underground mining. 1 Such structure is used to support the overburden and provide a safe working environment for personnel and equipment. Thus, ensuring the stability of …
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Crown pillar, a remnant ore usually left in between open-pit to underground mining that supports the terrain and aids in carrying out underground mining operations safely and its stability is vital.
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The main empirical method to evaluate crown pillar stability was proposed by Carter (1992) as a stability chart and was upgraded by Carter (2014) with the scaled span concept which is commonly used in stope mines. However, these methods are not used to evaluate block cave mine crown pillars, with most of the analysis based on numerical ...
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In this study, the determination of crown pillar thickness for coal mining based on preventing water inrush has been performed successfully. The obtained results indicate that for the longwall mining operation with coal seam of 4 m, crown pillar thickness in the range of 100–250 m can be considered sufficient to prevent water …
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Crown pillars provide regional and local support by isolating the ground surface from underground mine workings. Topography above the underground mine may be a relatively flat ground surface or an open-pit structure. Depending on what lies above and design of the underground mine, the crown pillar behaviour will differ. In …
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A comparison of the cost of mining the natural crown pillar, processing the ore and constructing the artificial crown pillar with the market price of the gold obtained showed a profit of 30%.
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Many pillars remain in underground mines when the room-and-pillar mining technique is used. The pillars can protect the equipment and ensure the safety of workers during the deep mining of solid mineral resources, where structures are left between two or more underground openings (Li, Zhou, Wang, & Liu, 2017).Therefore, proper pillar …
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Joan Atieno. Crown pillars provide regional and local support by isolating the ground surface from underground mine workings. Topography above the underground mine may be a relatively flat ground ...
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A comparison of the cost of mining the natural crown pillar, processing the ore and constructing the artificial crown pillar with the market price of the gold obtained showed a profit of 30%.
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Thickness of the crown pillar is critical for safe operation in the mine. Therefore, before underground mining, the crown pillar thickness must be determined …
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The Scaled Span approach, developed in the late 1980's, provides an effective means for empirically sizing a rock crown pillar over a near-surface excavation based on …
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the crown pillar for a gold mine orebody existing below a tailing dam are studied in detail by Chen and Mitri (2021). Numerical modelling is mostly carried out using the softwares like Fast Lagrangian Analysis of Continua in 3D (FLAC3D) (Li et al. 2013), CPillar, where the rock strata is stratied and Three-dimensional Distinct Element Code
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To design an optimal crown pillar, a comprehensive investigation is necessary for each mine, focusing on the behaviour of the crown pillar regarding stress distribution, roof convergence, and yielding zones under the relaxation zone (Hosseini et al. Citation 2023). Geological and geo-mining conditions vary greatly between mines due …
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The results indicate that increasing the crown pillar thickness from 5 to 8 m reduces maximum vertical deformation by 55.8% and the maximum extent of yielding zones from 2.2 to 0 m.
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The open stope mining method is the most common underground extractive technique used in Australian metalliferous mines. The crown pillar as it stands in the vertical plane between two open stopes is an integral part of the global stability of an underground metal mine. The stability of crown pillars are significantly affected by the mechanical and …
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This division allows separate assessments of the area above the crown pillar for open pit mining and below for underground mining. By considering geological factors, economics, and other relevant considerations, the authors aim to optimize extraction by employing the most suitable mining methods for each portion [12,13,14]. Pre-selecting …
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Shirengou iron mine in Hebei Province, China is now under transition from open pit to underground mining. During this process, the unstable failure risk of crown pillar is growing as a result of underground mining, fault activation and water seepage. To monitor the stability of the crown pillar, a microseismic monitoring system was …
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Surface crown pillars are formed above all underground mining operations situated near the ground surface, as shown in Fig. 1. As mining proceeds towards the …
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A crown pillar is to be designed in the transition region from surface to underground operations. Crown pillar dimensioning effects the overall ore recovery in such small-scale ore bodies.
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Pillar Robbing, Technique of. Pillar robbing is the method and technical process of ore pillar recovery based on the comprehensive consideration of various factors such as the ground pressure behavior law of the mine, pressure-bearing capacity of the pillar, output distribution of each stoping step, and economic benefit.
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Crown pillar design in highly dipping coal seam. 1. Introduction. In horizon mining, stability of horizon is very important for safe exploitation of coal block developed between two horizons in a highly dipping seam. Under such conditions, crown and sill pillars are generally left in the coal seam for protecting the horizons.
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Abstract. Minerals are now being extracted from deep mines due to drying up of resource in shallow ground. The need for suitable supports and ground control …
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