##tihuan2##The quantitative characterization of rock mass and stress changes induced by mining activities is crucial for structural stability monitoring and disaster early warning. This paper investigates...
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##tihuan2##As a result, in-situ stresses around drifts, ramps, and stopes in underground mines are quite different from far field or pre-mining stresses. The purpose of this research is to develop a simple and practical methodology for determining in-situ stresses.
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##tihuan2##orientations of the horizontal stresses observed underground. Recently, WSM geophysicists studying deep-seated stresses have developed a model of how stress magnitudes vary with depth in the crust. They have devoted relatively little attention to near-surface stresses, however. This paper explores the relationships between deep-seated …
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##tihuan2##Knowledge of ground stresses is crucial for ground control activities such as the design of underground openings, selection of support systems, and analysis for stability. However, it is a known fact that far field stresses experience changes in orientation and magnitude due to the presence of geological structures and due to the excavations …
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##tihuan2##Mining safety refers to practices, procedures, and regulations aimed at controlling and managing the various hazards associated with every step of the mining process, from exploration to reclamation. By taking well-strategized measures to prevent accidents, injuries, and fatalities during operations, companies can effectively safeguard …
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##tihuan2##The bord and pillar method is commonly employed in Indian underground coal mines, and the extraction rate varies between 30 and 65%. During pillar extraction, pillars are subjected to severe stress conditions. Due to this, the natural state of stress equilibrium is disturbed, resulting in severe strata control problems leading to sudden, …
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##tihuan2##mines are operated at greater depths using high capacity machinery [, 12]. Increasing mining depth and upgrading of mine mechanization are the prime causes of heat hazard, which is a major concern in deep underground mines []. 3 As the mining depth increases, it becomes more dicult to maintain a comfortable working environment for miners
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##tihuan2##A GUIDE TO ROUTINE SEISMIC MONITORING IN MINES by A J Mendecki, G van Aswegen and P Mountfort ISS International Limited P.O. Box 12063, Die Boord, 7613, RSA ... Figure 1 Apparent stresses of selected seismic events with equal local magnitudes m . 1.0 in a South African Gold Mine. The ratio of the highest to the lowest apparent
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##tihuan2##Mining companies archive personnel data (albeit for a limited period and often in paper-based files). Where available, records were reviewed for specific job descriptions and to identify gaps in employment histories. For the studies on diamond miners, tailings and soil samples were collected from three different mines. ...
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##tihuan2##The topicality of this work is due to the importance of developing such a new-generation monitoring computer-aided measurement system intended for ensuring the safety of mining works and coal mining that would allow one to monitor all required parameters and defects in a massif. Additional optic-fiber losses have been investigated …
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##tihuan2##Mine Safety and Health Administration (MSHA) to acquaint the reader with a specific area of mining. This manual defines "hot" work sites, heat stress, heat strain, and the natural coping mechanisms of the human body. Also explained are heat-related in-juries and disorders, an overview of treatments, and control methods used in the mines.
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##tihuan2##Semantic Scholar extracted view of "ground stresses in the Canadian hardrock mines: An update" by B. Arjang et al.
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##tihuan2##From the study in FLAC-3D for estimating stresses in the mine and Pillar-X, it can be inferred that the stresses inside the pillar exist in the range of ⁓5–8 MPa. For further analysis, the highest value of 8 MPa is assumed to be the value of stress in Pillar-X. To maintain a Factor of Safety of 1.5 or higher, the pillar strength cannot fall ...
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##tihuan2##Understanding of the stresses induced in beams by bending loads took many years to develop. Galileo worked on this problem, but the theory as we use it today is usually credited principally to the great mathematician Leonard Euler (1707–1783). As will be developed below, beams develop normal stresses in the lengthwise direction that vary …
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##tihuan2##The in situ stresses of some coal mines in China were tested by hydraulic fracturing method, and it was found that the maximum horizontal stress is 0.5–2 times the vertical stress, and that the stresses are generally different in different directions (Kang et al., 2010). Min et al. (2004) studied cracks evolution with the incremental ...
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##tihuan2##Mining Engineering Department, K ing Abdulaziz University, Jeddah, Kingdom of Saudi Arabi a. ... stresses), whereas inter nal stresses contained o f residual stresses. Var ious other .
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##tihuan2##WMSD. Due to the uniqueness of the workplace at mines, generic solutions will not necessarily fully address ergonomics-related risks at all mines. It is therefore recommended that mine-specific ergonomics programmes be considered as a method for the introduction and implemen-tation of ergonomics programmes in the workplace at mines.
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##tihuan2##The stress-strain state can be affected by numerous geological and mining factors i.e. depth, mechanical parameters of the rock mass, the presence of faults, previous mining operations in case of multiple seam extraction and by the influence of the current longwall mining process. Considering this fact the advanced measurement plan was …
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##tihuan2##There are many in situ stress measurement methods nowadays, the ISRM suggested two methods for in situ stresses measurement: overcoring methods and the hydraulic fracturing methods. In order to study the distribution law of in situ stress field in the deep position of Hongyang coal mine, 3 points of in situ stress measurement were …
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##tihuan2##In order to ensure the safety of tunnel maintenance and mining operation of coal mines in Xuzhou, in-situ rock stresses are measured in 5 coal mines of Xuzhou mining area at a depth of over 800 m ...
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##tihuan2##The statistical results showed that the in situ stresses in Huainan mining area were characterized by a strike-slip faulting regime. Both the horizontal and vertical principal stresses increased ...
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##tihuan2##Canadian crustal stresses and their application in mine design Author ARJANG, B 1 [1] Natural Resources Canada, CANMET, Mining and Mineral Sector, Ottawa, Ont., Canada Conference title Mine Planning and Equipment Selection 1998 Conference name MPES : International Symposium on Mine Planning and Equipment Selection (7 ; Calgary 1998 …
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##tihuan2##The special environment in which rock mass of deep engineering is located determines its geological and mechanical characteristics. The environment is the complex mechanical environment of "Three Highs and One Disturbance", which mainly refers to high geostress, high temperature, high water pressure, and mining disturbance [1], [2], …
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##tihuan2##In situ rock stresses are directly associated with the stability of underground openings and thus the state of in situ rock stress is a crucial factor for the design of underground excavations. The consequences of the rock stresses are rock …
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##tihuan2##Stress measurement at 11 points and 3 levels with overcoring technique were carried out in Xincheng Gold Mine. A series of new theories and techniques were used to ensure the reliability and accuracy of the measurements. From the measurements in—situ stress state and its distribution regularities along level and depth were obtained.
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##tihuan2##In situ and induced stresses Introduction Rock at depth is subjected to stresses resulting from the weight of the overlying strata . and from locked in stresses of tectonic origin. When an opening is excavated in this . rock, the stress field is locally disrupted and a new set of stresses are induced in the rock surrounding the opening.
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##tihuan2##Knutsson, S. (1981). "Stresses in the hydraulic backfill from analytical calculations and in-situ measurements." Proc., Conf. on the Application of Rock Mechanics to Cut and Fill Mining, Lulea, Sweden, 261–268.
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##tihuan2##PDF | On Jun 1, 1992, Moe Momayez published Application of Kaiser Effect to measure in-situ stress in underground mines | Find, read and cite all the research you need on ResearchGate
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##tihuan2##Question: 7.3-1 The stresses acting on an element are ??-750 psi..-600 psi, and ?.rv-400 psi. Deter- mine the principal stresses and show them on a sketch of a properly oriented element. Oy xy Ox ry ?? PROBLEMS 7.3 …
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