Performance Evaluation of Underground Mine Communication and Monitoring Devices: Case Studies

Communication and environmental monitoring play a major role in underground mining both from production and safety point of view. However, underground mining communication as well as monitoring devices encounter several challenges because of the nature of underground features and characteristics. Lack of real time information from underground workings may hamper production and create serious safety risks. Proper communication and monitoring devices are inevitable requirements for better production and improved safety. Communication and environmental monitoring devices are basic element of underground mine infrastructure. This paper describes the performance of communication and monitoring devices being used in underground mines. An attempt has been made to assess the safety risks by these devices which may dictate future research directions.

Towards Extracting Absolute Roughness From Underground Mine Drift Profile Data

The purpose of this paper is to demonstrate a technique to utilize underground mine drift profile data for estimating absolute roughness of an underground mine drift in order to implement the Darcy-Weisbach equation for mine ventilation calculations. This technique could provide mine ventilation engineers with more accurate information upon which they might base their ventilation systems designs. This paper presents preliminary work suggesting that it is possible to estimate the absolute roughness of drift-like tunnels by analyzing profile data (e.g., collected using a scanning laser rangefinder). The absolute roughness is then used to estimate the friction factor employed in the Darcy-Weisbach equation. The presented technique is based on an analysis of the spectral characteristics of profile ranges. Simulations based on real mine data are provided to illustrate the potential viability of this method. It is shown that mining drift roughness profiles appear similar to Gaussian profiles

Evaluation of a ToF Camera for Remote Surveying of Underground Cavities Excavated by Jet Boring

Cigar Lake is a high-grade uranium deposit, located in northern Saskatchewan, Canada. In order to extract the uranium ore remotely, thus ensuring minimal radiation dose to workers and also to access the ore from stable ground, the Jet Boring System (JBS) was developed by Cameco Corporation. This system uses a high-powered water jet to remotely excavate cavities. Survey data is required to determine the final shape, volume, and location of the cavity for mine planning purposes and construction. This paper provides an overview of the challenges involved in remotely surveying a JBS-mined cavity and studies the potential use of a time-of-flight (ToF) camera for remote cavity surveying. It reports on data collected and analyzed from inside an experimental environment as well as on real data acquired on site from the Cigar Lake and Rabbit Lake mines.

Design of a Novel Auto-Rotating UAV Platform for Underground Mine Cavity Surveying

The purpose of this paper is to investigate the potential for use of UAVs in underground mines and present a prototype design for a novel autorotating UAV platform for underground 3D data collection.

An Evaluation of Carbon Concentrations Associted with Biodiesel Particulate Matter in an Underground Metal Mine

Exposure to diesel particulate matter from diesel exhaust has been shown to have adverse health effects in humans. In 2012 The International Agency for Research on Cancer classified diesel exhaust as a group 1 know human carcinogen. Because of the associated health effects, there has been a strong push to reduce the amount of diesel exhaust present in the mining industry. Biodiesel is one to the more common and promising control options used to reduce the amount of diesel particulate matter that is generated during fuel combustion. The use of biodiesel over petroleum diesel has been shown to reduce not only particulate matter, but hydro carbon and carbon monoxide mass emissions as well. Personal and area samples were collected at an underground metal mine in the northwestern United States to evaluate the current blend of B70 biodiesel. The objective of this research was to evaluate the carbon levels associated with diesel particulate matter generated from the combustion of a B70 biodiesel. Data was also compared to past studies on which diesel particulate matter from petroleum diesel was evaluated. Samples were taken on four separate four day campaigns between March and October of 2014. Area samples were taken from 7 different areas in the mine and personal samples were taken from a 20 person cohort. The equipment used for sampling was compliant with the NIOSH 5040 method. Statistical analysis of the results was done using Minitab 17 software. The statistical analysis showed that the total carbon concentrations from biodiesel were well below the MSHA exposure limit. Results also showed that organic/elemental carbon ratios were consistent with past studies as the concentrations of organic carbon were significantly higher than those of elemental carbon.

Automation of an underground mining vehicle using reactive navigation and opportunistic localization

This paper describes the implementation of an autonomous navigation system onto a 30 tonne Load-Haul-Dump truck. The control architecture is based on a robust reactive wall-following behaviour. To make it purposeful we provide driving hints derived from an approximate nodal-map. For most of the time, the vehicle is driven with weak localization (odometry). This need only be improved at intersections where decisions must be made - a technique we refer to as opportunistic localization. The truck has achieved full-speed autonomous operation at an artificial test mine, and subsequently, at a operational underground mine.

Reactive navigation and opportunistic localization for autonomous underground mining vehicles

This paper describes an autonomous navigation system for a large underground mining vehicle. The control architecture is based on a robust reactive wall-following behaviour. To make it purposeful we provide driving hints derived from an approximate nodal-map. For most of the time, the vehicle is driven with weak localization (odometry). This need only be improved at intersections where decisions must be made – a technique we refer to as opportunistic localization. The paper briefly reviews absolute and relative navigation strategies, and describes an implementation of a reactive navigation system on a 30 tonne Load-Haul-Dump truck. This truck has achieved full-speed autonomous operation at an artificial test mine, and subsequently, at a operational underground mine.

Symptoms of heat illness in surface mine workers

Objective: To assess the symptoms of heat illness experienced by surface mine workers. Methods: Ninety-one surface mine workers across three mine sites in northern Australia completed a heat stress questionnaire evaluating their symptoms for heat illness. A cohort of 56 underground mine workers also participated for comparative purposes. Participants were allocated into asymptomatic, minor or moderate heat illness categories depending on the number of symptoms they reported. Participants also reported the frequency of symptom experience, as well as their hydration status (average urine colour). Results: Heat illness symptoms were experienced by 87 and 79 % of surface and underground mine workers, respectively (p = 0.189), with 81–82 % of the symptoms reported being experienced by miners on more than one occasion. The majority (56 %) of surface workers were classified as experiencing minor heat illness symptoms, with a further 31 % classed as moderate; 13 % were asymptomatic. A similar distribution of heat illness classification was observed among underground miners (p = 0.420). Only 29 % of surface miners were considered well hydrated, with 61 % minimally dehydrated and 10 % significantly dehydrated, proportions that were similar among underground miners (p = 0.186). Heat illness category was significantly related to hydration status (p = 0.039) among surface mine workers, but only a trend was observed when data from surface and underground miners was pooled (p = 0.073). Compared to asymptomatic surface mine workers, the relative risk of experiencing minor and moderate symptoms of heat illness was 1.5 and 1.6, respectively, when minimally dehydrated. Conclusions: These findings show that surface mine workers routinely experience symptoms of heat illness and highlight that control measures are required to prevent symptoms progressing to medical cases of heat exhaustion or heat stroke.

Evaluation of internal navigation sensor suites for underground mining vehicle navigation

This paper describes a series of trials that were done at an underground mine in New South Wales, Australia. Experimental results are presented from the data obtained during the field trials and suitable sensor suites for an autonomous mining vehicle navigation system are evaluated.

Stresses and stability of a mine paste fill

Se describe el comportamiento de los rellenos de pasta de las cámaras primarias de la mina de Aguas Teñidas y se calcula la resistencia que deben tener dichos rellenos para que no se desmoronen las paredes de los mismos que quedan expuestas al extraer las cámaras secundarias.Abstract:This article presents the study carried out at an underground mine to understand the stress distribution in the paste fills and to calculate the stability of the paste walls. The mine is operated using sublevel stopes. Three-dimensional numerical models designed with the FLAC 3D software are used to study the distribution of the vertical stresses in the paste. The numerical models have demonstrated that an arc-like effect is produced in the paste fills of the primary stopes. This effect relieves the vertical stresses and increases the stability of the exposed paste wall fill. Based on the results of the numerical models, in the 30m high secondary stopes, the arc effect starts to be evident only in paste walls with a width/height ratio lower than 0.8. 3-D calculations show that the use of Mitchell, R. J. et al. (1982) formula may be risky when estimating the fill stability in secondary stopes.

基于粗糙集和多Agent系统的知识挖掘

通过优化知识表达系统中条件属性对决策属性的依赖度,深入研究了粗糙集并与多Agent系统相结合。利用离散粒子群算法,提出一种基于粒子群优化的粗糙集知识约简算法,该算法解决了启发式算法无法全局搜索进行约简的问题。最后通过在矿井中调度信息的应用验证了有效性。

金川矿山岩体移动规律及竖井变形、破坏机理研究

The Jinchuan Nickel Mine is the largest underground mine with cut-and-fill mining in China. It is very difficult to be exploited for very low safety stability of rock mass caused by complex geological conditions, developed faults, cracked rock mass and high stress. In this paper, the laws of rock mass movement、mechanics of shaft deformation and destroy were analyzed based on the collection of date, the detailed field engineering investigations, ground movement monitoring by GPS, theoretical analysis and numerical simulation. According to the GPS monitoring result of ground surface movement, there are different ground movement characteristics among the three Mine area of Jinchuan Nickel Mine. In No. 2 Mine area, the ground movement funnel with apparent asymmetry is developing, the influence scope is larger in the up faulted block than in the down faulted block, and the centre of ground movement is moving along the up faulted block direction with increasing depth of mining. Moreover, the tunnels in the corresponding area with the centre of ground movement are damaged seriously. In Longshou Mine area, the ground movement funnel is also developing, but the moving path and the nonlinear characters are more sophisticated because of the long-term effects of open excavating and the effects of underground mining together. In No. 3 Mine area, the underground mining impact on surface is not serious for the time of mining activity is not for long, but the ground movement funnel is also forming now. The underground mining has caused widespread land subsidence in Jinchuan Nickel Mine area, but the phenomena of surface raise appeared in some partial areas of Longshou Mine area and No. 3 Mine area. Analysis proved that the reason for the open pit bottom raise is the slope deformation activation caused by the excavation from open pit into underground mine; and that the raise of surface in No.3 Mine area is caused by the effect of elastic foundation due to underground mining. Although the GPS Monitoring results show the amount of subsidence is increasing constantly, the subsidence rate has a descending tendency with fluctuation in Jinchuan No. 2 Mine area. The subsidence rate curve is a time function and exists an extreme point, the rate increasing before extreme point and decreasing after the extreme point ,but the scale of decreasing rate will be very small after the rate decreasing up to a certain degree, moreover, the characteristics is different among different areas, which have some relation with the distance to the mining section and the dip of the ore body. ArcView is GIS software, which we adopted as a development platform, and made secondary development by its development language “avenue”, through which we developed a ground movement analysis and forecast System for Jinchuan Nickel Mine, which contain three modules : management of ground movement information; analysis and evaluation of ground movement; and ground movement forecast. In the module of evaluation, using the technique of MATLAB6.5 program with VB6.0, the system can achieve the ANN prediction model for GPS monitoring data, data preparation results analysis and model integrated was realized by Avenue programming. Finally, the author analyzed the mechanical of deformation and destroy of the No. 14 shaft, and its repair and artificial-support effectiveness also given detailed demonstration in various aspect. The result showed that the reason for the destroy of No. 14 shaft is underground mining, and being the case, the destroy of the shaft also has its special features, which mainly contains forked stress contour for mining steep ore and fault effect caused by mining activities. The repair and artificial-support played some restrictions on the rock mass movement and deformation, but did not show a strong or marked effect. With the increasing of mining depth and large-scale, the closure rock of the shaft will still deformed, even be destroyed.

La perception du risque sous terre : l'exemple des mineurs de fond de l'Abitibi-Témiscamingue

Cette thèse porte sur la perception du risque sous terre. Nous voulons comprendre comment les mineurs de fond de la région de l’Abitibi-Témiscamingue au Québec perçoivent les risques inhérents à leur métier et comment ils y réagissent. L’organisation du travail, le fonctionnement d’une mine souterraine et les rapports de production sous terre retiennent d’abord notre attention. Le concept de risque représente un concept relativement jeune qui a intéressé de nombreux auteurs. Un tour d’horizon des diverses approches nous permettra de définir ce concept en nous appuyant plus spécialement sur les travaux de Mary Douglas. Cependant, nous avons conduit notre enquête à partir d’un cadre théorique se fondant principalement sur la sociologie de Pierre Bourdieu. Notre hypothèse défend l’idée que dans leur perception du risque, les mineurs de fond de l’Abitibi-Témiscamingue font montre d’un sens pratique qui repose surtout sur la prise en charge individuelle de la sécurité, le rapport à la prime de rendement et un certain sentiment de l’inéluctabilité du danger. Vingt entrevues semi-dirigées et la technique classique de l’observation participante ont servi à la collecte de données. L’analyse des récits de travail a donné lieu à une typologie distinguant trois groupes de mineurs. Nous avons préalablement décortiqué chacun des récits afin de dégager un modèle de base. Les résultats de l’analyse nous obligent à réviser notre hypothèse initiale et à ne pas conclure trop rapidement au fatalisme des mineurs de fond témiscabitibiens.

Sistema de gestión de las aguas del complejo minero de carbón de S.A.M.C.A. en la Val de Ariño (Teruel)

La finalidad de este proyecto consiste en realizar un estudio de la gestión del agua del complejo minero de carbón que SAMCA tiene en Ariño, así como recoger distintas iniciativas de mejora para su optimización en la actualidad. Por otro lado, también se pretende analizar la problemática de la posible clausura de la mina de interior “Sierra de Arcos”, una de las principales aportadoras de agua al sistema, y se presentan las posibles opciones para el aprovechamiento óptimo de las aguas superficiales y subterráneas de cara al futuro de la explotación para garantizar un balance hídrico en el que los aportes y los consumos de agua estén equilibrados. Después de este exhaustivo análisis, se deciden cuáles son las mejores opciones desde un punto de vista tanto técnico como económico. ABSTRACT The purpose of this Project is to carry out a study about the management of SAMCA´s coalmine complex in Ariño, as well as gathering a range of initiatives to help optimizing the present system. Additionally, the study sets out to analyze the possible problems arising from the closing of “Sierra de Arcos” underground mine, contributor of one of the main sources of water into the system. Based on the analysis, a series of possible options are presented to reach the ideal utilization of the superficial and underground water. These proposals aim to ensure an optimal water balance sheet between the water contributions and the water consumptions. The results obtained from this exhaustive analysis are used to reach a conclusion for the project by presenting what are considered the best options from both, a technical and an economic point of view.