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Roadway Roof Support Design In Critical Areas At Anglo American Metallurgical Coal's Underground Operations, Ismet Canbulat
Roadway Roof Support Design In Critical Areas At Anglo American Metallurgical Coal's Underground Operations, Ismet Canbulat
Resource Operators Conference
In order to ensure the stability of roadways Anglo American Metallurgical Coal (AAMC) has developed an advanced roof support design methodology that integrates analytical, numerical and empirical modelling. This methodology currently is based on a deterministic approach (a single factor of safety against failure is calculated). However, an improved methodology, based on stochastic modelling technique, has also been developed and currently being evaluated. The main advantage of this methodology is that as the design is based on probability distributions of input parameters, the outcome is based on a distribution of factors of safety rather than a single factor of safety. …
A Numerical Simulator Of Outbursts Of Coal And Gas, Sheng Xue, Gang Wang, Yucang Wang, Jun Xie
A Numerical Simulator Of Outbursts Of Coal And Gas, Sheng Xue, Gang Wang, Yucang Wang, Jun Xie
Resource Operators Conference
An outburst of coal and gas in underground coal mines may occur when stress condition and coal failure combine with rapid gas desorption. A mechanical and fluid coupled numerical simulator, SimBurst, has been developed to simulate the initiation process of the outburst, as a first step to model the whole process of the outburst. This paper describes the simulator and a simple model set up with the simulator to model the initiation of an outburst in roadway excavation to illustrate the methodology and approach with the SimBurst. The model simulated the basic features of an outburst initiation process, including coal …
Global Trends In Coal Mine Horizontal Stress Measurements, Christopher Mark, Murali Gadde
Global Trends In Coal Mine Horizontal Stress Measurements, Christopher Mark, Murali Gadde
Resource Operators Conference
Knowledge of in situ stresses is fundamental to many studies in earth sciences, and coal mine ground control is no exception. During the past 20 years, it has become clear that horizontal stress is a critical factor affecting roof stability in underground coal mines. The theory of plate tectonics and the World Stress Map (WSM) project has been extremely helpful in explaining the sources and the 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 …
Recovery Of Stored Gas In Coal By Nitrogen Injection - A Laboratory Study, Raul Florentin, Naj Aziz, Dennis Black, Long Nghiem, Kemal Baris
Recovery Of Stored Gas In Coal By Nitrogen Injection - A Laboratory Study, Raul Florentin, Naj Aziz, Dennis Black, Long Nghiem, Kemal Baris
Resource Operators Conference
With increasing worldwide concern on Green House Gas (GHG) emission and its reduction, significant interest is now directed toward finding a practical and economical ways of enhancing methane gas containment in coal deposits. Carbon dioxide sequestration has been tried successfully for the recovery of methane from coal measures rocks. A laboratory study was undertaken to examine the effect of displacing the adsorbed gases in coal with N2 injection. To study the feasibility of removing the initially adsorbed gas from coal with another gas, tests were carried out using an in-house built multi-function outburst research rig (MFORR). Accordingly the following laboratory …
Mine-Scale Numerical Modelling Of Longwall Operations, Abouzar Vakili, John Albrecht, William Gibson
Mine-Scale Numerical Modelling Of Longwall Operations, Abouzar Vakili, John Albrecht, William Gibson
Resource Operators Conference
Elastic three dimensional Boundary Element (BE) codes are commonly used in the coal industry to model the induced stresses and rock mass response to longwall mining. While these models are often easy to build and quick to run, it is questionable whether these elastic models are capable of accurately simulating the highly non-linear rock mass response observed in longwall operations, in particular the complex caving and goaf behaviour of the overlying strata and resulting surface subsidence. This study presents a comparison between modelling results obtained from the finite difference (FD) code FLAC3D and elastic BE code Map3D for a generic …
The Use Of Cfd Modelling As A Tool For Solving Mining Health And Safety Problems, Ting Ren, Rao Balusu
The Use Of Cfd Modelling As A Tool For Solving Mining Health And Safety Problems, Ting Ren, Rao Balusu
Resource Operators Conference
Many safety and health problems in the coal mining industry involve the understanding and analysis of the mechanism of fluid or gas flow, including goaf gas migration, face ventilation and dust dispersion. Computational Fluid Dynamics or CFD has become a powerful tool to assist mining engineers and find solutions to these problems. The use of CFD modelling in goaf gas management and drainage, goaf inertisation for heating control, and longwall dust control strategies is summarised.
Stability Analysis And Optimum Support Design Of A Roadway In A Faulted Zone During Longwall Face Retreat - Case Study : Tabas Coal Mine, Ali Sahebi, Hossein Jalalifar, Mohammad Ebrahimi
Stability Analysis And Optimum Support Design Of A Roadway In A Faulted Zone During Longwall Face Retreat - Case Study : Tabas Coal Mine, Ali Sahebi, Hossein Jalalifar, Mohammad Ebrahimi
Resource Operators Conference
Stability analysis of a longwall, East 1 tailgate (E1TG) of Tabas underground coal mine is presented. The mine extracts coal by both longwall and room and pillar methods. The mine is designed to produce 1.5 million tonnes of coal annually. The roadways have a rectangular profile of 4.5m width and 3.5m height. The field investigations and the geomechanical characteristics of rocks showed that the rock masses are weak, requiring a suitable support system. The roadway is intersected by a major fault zone. To investigate the effect of the fault zone on roadway stability, in particular during the face retreat, extensive …
The Role Of Acarp In Supporting Australian Coal Research, Bruce Robertson
The Role Of Acarp In Supporting Australian Coal Research, Bruce Robertson
Resource Operators Conference
The Australian coal industry is significant in many ways and is serviced by a number of research activities, but it is unique, globally, in relation to the Australian Coal Industry Research Program (ACARP) – a Research & Development (R&D) investment program funded by a 5c per saleable tonne levy and owned and managed by representatives of the industry. ACARP has been in operation since 1992 and currently supports research activities into the safety, sustainable production and marketing of coal (but excluding the sustainable use of coal). With an expenditure of about A$15 million per year, the program supports a critical …
Outburst Threshold Limits - Current Research Outcomes, Dennis Black, Naj Aziz
Outburst Threshold Limits - Current Research Outcomes, Dennis Black, Naj Aziz
Resource Operators Conference
Since outburst threshold limits were imposed on Bulli seam mines in 1994 the occurrence of coal and gas outburst incidents have virtually been eliminated from the Australian coal industry. With the reduction in incidents and therefore hazard to the industry there has been a corresponding drop in research effort in this area. Some mines have in recent years reviewed and raised threshold limit values and non-Bulli seam mines accept the method of threshold limit value determination introduced by GeoGAS, based upon the DRI900 concept. Detailed analysis of gas desorption data from a variety of Australian coal mines, representing different coal …
Case Study Of Ethane Emissions At Mandalong Mine, Cambridge Claassen, Basil Beamish
Case Study Of Ethane Emissions At Mandalong Mine, Cambridge Claassen, Basil Beamish
Resource Operators Conference
Gas chromatograph analysis of sealed goaf areas at Mandalong Mine show that ethane concentrations of 30 ppm are present in older areas and up to 225 ppm have been recorded in more recent areas. Such high levels of ethane would normally be considered an indication of spontaneous combustion for many mines. However, at Mandalong Mine despite these high ethane levels, no significant carbon monoxide is recorded, indicating that the ethane being measured is a result of gas desorption from the coal over time. Generally, there is a sympathetic evolution pattern between ethane and methane, with some areas of the mine …
Amcmrr - An Analytical Model For Coal Mine Roof Reinforcement, Mark Colwell, Russell Frith
Amcmrr - An Analytical Model For Coal Mine Roof Reinforcement, Mark Colwell, Russell Frith
Resource Operators Conference
An analytical model for coal mine roof reinforcement (AMCMRR) has been developed. AMCMRR utilises a Factor of Safety (FOS) approach which is commonly used in all forms of engineering. The starting point in the development of AMCMRR was an existing analytical roof behaviour and roof support design methodology/model originally developed by the second author. This technique was being successfully utilised in the Australian underground coal industry for roof support evaluation and design prior to and during the course of the ALTS 2006 research project and when used was essentially calibrated on a site by site basis. It has long been …
Shear Testing Of 28mm Hollow Strand "Tg" Cable Bolt, Peter Craig, Naj Aziz
Shear Testing Of 28mm Hollow Strand "Tg" Cable Bolt, Peter Craig, Naj Aziz
Resource Operators Conference
Cable bolts were introduced to the coal mining industry in the early 1980’s mainly for roadway reinforcement as a secondary means of support. Their application is dictated by the nature of the stratification, ground stress conditions and the size of the opening. Double shearing tests were carried out on the 28 mm hollow strand Jennmar “TG” cable bolt, two tests were conducted to evaluate the shearing characteristics of the bolt and to gain a better understanding of the shearing behaviour of the cable. The first test was limited by a 50 mm travel on the testing machine and produced a …
Non Destructive Integrity Testing Of Rock Reinforcement Elements In Australian Mines, Wauter Hartman, Benoit Lecinq, John Higgs, David Tongue
Non Destructive Integrity Testing Of Rock Reinforcement Elements In Australian Mines, Wauter Hartman, Benoit Lecinq, John Higgs, David Tongue
Resource Operators Conference
Non-destructive testing, used to study the integrity of the bolting systems in underground mining and civil construction industries, as an alternative method to the current hydraulic pull testing practice, is described. Non-destructive tests were carried out on a total of 227 bolts, comprising 89 rebar type bolts, 124 cable bolts and 14 splitsets were tested in four mines across Australia. The purpose of these tests was to confirm the validity of the testing methodology for rock reinforcement systems used in mines and provide reassurance on bolt’s integrity, which could have been compromised during installation or affected by in-situ aggressive conditions …
Improving Emergency Management In Underground Coal Mines, David Cliff, John Grieves
Improving Emergency Management In Underground Coal Mines, David Cliff, John Grieves
Resource Operators Conference
The findings of ACARP funded research project C17008 - Optimising the collection of information for effective use in the event of an emergency at an underground coal mine is reported. The aim of this ACARP funded research project was to identify ways of optimising the information collection and reporting processes used in emergencies in underground coal mines to ensure rapid and effective response, minimising the risk to life. This was to be achieved through evaluating the current emergency management systems at mines, identifying good practice and also areas that needed improvement. There were three areas of focus for the project: …
Appin Colliery Explosion Reassessed, Bob Kininmonth
Appin Colliery Explosion Reassessed, Bob Kininmonth
Resource Operators Conference
The Judicial Inquiry into the Appin Colliery explosion on 23rd July 1979 made a specific finding that the fan starter box was the location of the initial ignition of gas. The subsequent Coronial Inquiry recognized the possibility of the fan starter box being the source but also recognized the possibility that the Deputy’s flame safety lamp could have been the trigger. Neither Inquiry detailed the mistakes that must have been made for either of those options to be the cause. It is contended that the flow of factual information at such Inquiries can be influenced by the high-profile legal representation …
Mine Gas Initiative North Rhine-Westphalia - Part Of Energyagency.Nrw Platform For Economy, Engineering And Research, Axel Preusse, Joerg Kraemer
Mine Gas Initiative North Rhine-Westphalia - Part Of Energyagency.Nrw Platform For Economy, Engineering And Research, Axel Preusse, Joerg Kraemer
Resource Operators Conference
An overview of the Mine Gas Initiative NRW, part of the EnergyAgency.NRW in North Rhine-Westphalia (NRW), Germany, is presented. It covers the role of the initiative in areas relating to energy production from mine gas, enhancement of mine security through utilisation of mine gas and enforcement of climate protection by avoiding methane emissions into the atmosphere. Achieved objectives and future developments will be presented.
Innovations In Mine Roadway Stability Monitoring Using Dual Height And Remote Reading Electronic Telltales, David Bigby, Keith Macandrew, Ken Hurt
Innovations In Mine Roadway Stability Monitoring Using Dual Height And Remote Reading Electronic Telltales, David Bigby, Keith Macandrew, Ken Hurt
Resource Operators Conference
Rockbolting telltales are now an internationally established means of providing preemptive warnings of roof falls. The dual height telltale, providing an immediate visible measurement distinguishing between movement above and below the rockbolted height, is the most widespread version. The dual height telltale was first developed by British Coal in the early 1990's as rockbolting was introduced to replace steel arch support and the success of this support system in deep coal mines has been widely ascribed to the use of this safety device. Since its adoption, many permutations and improvements on the basic design have been developed and applied worldwide …
Cfd Simulation Of Underground Coal Dust Explosions And Active Explosion Barriers, David Humphreys, Greg Collecutt, David Proud
Cfd Simulation Of Underground Coal Dust Explosions And Active Explosion Barriers, David Humphreys, Greg Collecutt, David Proud
Resource Operators Conference
Computational fluid dynamics (CFD) is being applied to the study of coal dust explosions and their suppression in underground coal mines. As part of an ACARP funded project to develop a practical active explosion barrier, CFD is being used to simulate the explosion dynamics in simple mine roadways before examining the design requirements for an active explosion barrier. Results of these simulations will be used to develop the specifications for a prototype active explosion barrier with a reduced requirement for large scale testing. Results to-date are very encouraging with validation of the model behaviour against a range of explosion conditions …
Modification Of Four-Section Cut Model For Drift Blast Design In Razi Coal Mine - North Iran, Mohammad Hossaini, Hadi Poursaeed
Modification Of Four-Section Cut Model For Drift Blast Design In Razi Coal Mine - North Iran, Mohammad Hossaini, Hadi Poursaeed
Resource Operators Conference
Four-section cut, a model similar to Swedish method, is an empirical method for blasting design in underground excavations. This method, often, has been used in excavating tunnels with cross section area of more than 10m2. Using the model for smaller tunnels needs some modifications to achieve proper quantity of the parameters. In this paper, four-section cut method has been modified for designing patterns for tunnels with cross section area of less than 10 m2. The applicability of the modified version has been examined through several blasting cycles and the ultimate optimized blasting pattern has been obtained. The previous blasting pattern …
Managing The Geotechnical Aspects Of Longwall Face Recovery, David Hill
Managing The Geotechnical Aspects Of Longwall Face Recovery, David Hill
Resource Operators Conference
Longwall face recovery is almost certainly the most involved recurring geotechnical problem faced by operators, with major loss potential should problems occur. The outcomes of an industry sponsored (ACARP) research project on the geotechnical issues associated with conventional longwall recoveries is presented with updates the experiences gained. A number of critical features of the geotechnical environment, support design and mining geometry have a pronounced impact on ground control during take-off. A model of roof behaviour at the take-off point has been developed and validated. Key geotechnical issues include low roof competency (ie weak roof), an adverse weighting environment, geological structure …
Impact Of Coal Properties And Operational Factors On Mine Gas Drainage, Dennis Black, Naj Aziz
Impact Of Coal Properties And Operational Factors On Mine Gas Drainage, Dennis Black, Naj Aziz
Resource Operators Conference
Many Australian underground coal mines have or are likely to encounter areas of increased gas content, which are difficult to drain. A number of factors have the potential to impact the overall efficiency and effectiveness of gas drainage from the mined coal seam. A mine based investigation was undertaken at an operating coal mine working in the gassy Bulli seam of Australia’s Illawarra coal measures. Gas production data from 279 inseam gas drainage boreholes was evaluated relative to a variety of coal properties and mine operational factors to determine the impact of each on gas production performance. Whilst the design …
Advanced Numerical Modelling Methods Of Rock Bolt Performance In Underground Mines, Chen Cao, Jan Nemcik, Naj Aziz
Advanced Numerical Modelling Methods Of Rock Bolt Performance In Underground Mines, Chen Cao, Jan Nemcik, Naj Aziz
Resource Operators Conference
Current developments in numerical modelling techniques are presented to investigate the load transfer between the steel bolt surface and resin encapsulation. Underground measurements of steel bolt performance indicate that amongst many parameters bolt profile configuration plays an important role in load transfer capacity between the bolt and resin that encapsulates the steel bolt. The short encapsulation pullout tests of roof bolt capacity can be successfully modelled and directly compared to the insitu pullout tests. Using the numerical modelling techniques, changes in the bolt profile can be studied in detail to provide a better understanding of the bolt reinforcement mechanism. In …
Applications Of Rfid And Mobile Technology In Tracking Of Equipment For Maintenance In The Mining Industry, Anthony Atkins, Lizong Zhang, Hongnian Yu
Applications Of Rfid And Mobile Technology In Tracking Of Equipment For Maintenance In The Mining Industry, Anthony Atkins, Lizong Zhang, Hongnian Yu
Resource Operators Conference
Supply Chain Management (SCM) is a crucial factor in reducing the down time in equipment maintenance in the mining industry. The paper describes a tracking and verification system using Radio Frequency Identification (RFID) and mobile RFID technology developed for an SME in the UK to monitor the assembly of parts for a manufacturing company. The system uses low cost passive tags (costing few cents) to provide information in real time using TCP/IP protocol which is internet compatible and can be viewed anywhere in the organisation worldwide to provide more effective management control. The RFID technology and mobile RFID equipment is …
Seismic Analysis Of Horseshoe Tunnels Under Dynamic Loads Due To Earthquakes, Navid Hosseini, Kazem Oraee, Mehran Gholinejad
Seismic Analysis Of Horseshoe Tunnels Under Dynamic Loads Due To Earthquakes, Navid Hosseini, Kazem Oraee, Mehran Gholinejad
Resource Operators Conference
Due to seismic events, such as earthquakes, the elastic waves propagate through a medium. The impact of these waves on underground structures is to provide dynamic forces and moments that may affect the stability of underground structures. The aim of this paper is to analyse the effects of seismic loads on the stability of horseshoe tunnels. As a case study, the stability state of the main access entry to C1 coal seam of Tabas collieries in Iran are analyzed using Phase2 software in static and dynamic states. It is often assumed that the effect of earthquakes on underground structures such …
Productivity Improvement From Economic Concept To An Engineering Tool, Kazem Oraee, Navid Hossein, Mohammadreza Soltani, Mehdi Amirafshari
Productivity Improvement From Economic Concept To An Engineering Tool, Kazem Oraee, Navid Hossein, Mohammadreza Soltani, Mehdi Amirafshari
Resource Operators Conference
In broad terms, productivity is defined as the ratio of all outputs to all inputs. In this paper, productivity is distinctly used as an engineering tool and from practical viewpoint. With such engineering look, productivity is an adequate tool for evaluation of the advancement in competitive market, work assessment, profit/loss analysis, decision and even developing or changing the activity. Productivity measurement seems to be an easy task but this is a misconception. In fact the concept remains to be one of the most complex and unknown criteria. It is for this reason that attempts have been made here to accurately …
Stability Analysis Of Tabas Coal Mine Roadway Using Empirical And Numerical Methods, Ali Sahebi, Hossein Jalalifar, Mohammad Ebrahimi, Ali Abdolrezaee
Stability Analysis Of Tabas Coal Mine Roadway Using Empirical And Numerical Methods, Ali Sahebi, Hossein Jalalifar, Mohammad Ebrahimi, Ali Abdolrezaee
Resource Operators Conference
Tabas coal mine is located south east of Tabas city, in Iran. The mine is the first fully mechanized coalmine in Iran that produces 4000 tonnes coal per day. Method of extraction is retreat longwall. One of the main problems in this mine, is the stabilization of entry roadways. In this research, five different methods were used to calculate potential rock loading on roadways, and according to the predicted rock load two types of section arches; V29 and V36, were considered for stabilization. Finally, the designed support system was numerically evaluated. From the numerical analyses, it was concluded that the …
Towards An Integration Information Infrastructure In Coal Mining Asset Management Application, Jorge Jemel Boneu, Leone Dunn, Peter Gibson
Towards An Integration Information Infrastructure In Coal Mining Asset Management Application, Jorge Jemel Boneu, Leone Dunn, Peter Gibson
Resource Operators Conference
Maintenance is recognised as the largest controllable cost among direct mining costs (Lewis and Steinberg 2001). Ironically, the ideal architecture for information systems and technologies for optimising maintenance functions has not been extensively studied. While many maintenance management approaches recognise the importance of understanding equipment functionality and performance monitoring, based in an integral range of information, extensive study to attain proper organisation of the information have not been undertaken. Degradation detection and prediction applications found in recent literature are generally for specific applications rather than generic (Lee et al 2006). The current study is intended to address Longwall mining equipment …
Calibrated Parameters For The Prediction Of Subsidence At Mandalong Mine, Ross W. Seedsman
Calibrated Parameters For The Prediction Of Subsidence At Mandalong Mine, Ross W. Seedsman
Resource Operators Conference
The consent conditions at Mandalong Mine require that subsidence deformations must not change the flood hazard category or subject a dwelling to deformation beyond safe surface and repairable (SSR) unless permission is granted by the effected landholder. The subsidence prediction in 2003 utilised an analysis of sag based on voussoir beams and of pillar compression based on foundation engineering principles. The model uncertainty for the sag analysis was assessed to be relatively high with a low parameter uncertainty, while for the pillar compression the model uncertainty was low but the parameter uncertainty was high. Up to June 2009, seven longwalls …
3d Geotechnical Models For Coal And Clastic Rocks Based On The Gsr, Terry Medhurst, Peter Hatherly, Binzhong Zhou
3d Geotechnical Models For Coal And Clastic Rocks Based On The Gsr, Terry Medhurst, Peter Hatherly, Binzhong Zhou
Resource Operators Conference
This paper provides the key outcomes and an example of Geophysical Strata Rating GSR analysis and modelling as undertaken in recently completed ACARP Project C17009. Various examples from the project demonstrate the use of GSR for overburden characterisation and hazard planning, tailgate stability and longwall face behaviour. Borehole spacings of 200 m or thereabouts, which are typical of Bowen Basin underground operations, allow geologically meaningful 2D and 3D modelling of GSR and other parameters derived from the geophysical logs. Plots of clay content and porosity can be used, depending on their relevance to the given strata behaviour, and/or as alternative …
Parameters Affecting Coal Seam Gas Escape Through Floor And Roof Strata, Abouna Saghafi, Hoda Javanmard, Douglas Roberts
Parameters Affecting Coal Seam Gas Escape Through Floor And Roof Strata, Abouna Saghafi, Hoda Javanmard, Douglas Roberts
Resource Operators Conference
Coal seams are compact gas reservoirs and can contain large volumes of methane (CH4) and carbon dioxide (CO2) which are the main constituents of coal seam gas (CSG). CSG is present in various volumes and concentrations across the mining regions in the coalfields of the Sydney and Bowen basins. The variations in actual gas volumes and relative concentration of these gases in coal could be due to different gas generation/accumulation rates and different adsorption capacity of the coals, but also because of the difference in the sealing capacity of the non-coal sediments enclosing the coal seams. It is postulated that …