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Proceedings Of The 2024 Resource Operators Conference, Naj Aziz, Kevin Marston, Zhenjun Shan

Resource Operators Conference

Proceedings of the 2024 Resource Operators Conference. All papers in these proceedings are peer reviewed. ISBN (ebook): 978-1-74128-396-9 ISBN (paperback): 978-1-74128-395-2.

A Structural Engineering Approach To Longwall Rock Mechanics In Massive Strata, Ian Gray, Tim Gibbons

Resource Operators Conference

Geotechnically massive strata behave as strong units, rather than the geologically massive description which describes the sedimentary formation. The consequence of such geotechnically massive units to mining is a series of problems associated with these units failing to break up into small blocks.

This paper deals with the determination of what constitutes geotechnically massive strata. This is essentially a function of the geology and the mechanical properties of the geological stratigraphic units that need to be combined into geotechnical units. The mechanical properties depend on the rock itself and on the structure in the form of joints and faults. The …

Outburst Control In The Wongawilli Seam, Dennis Black

Resource Operators Conference

The Wongawilli coal seam varies from 8 m to 10 m thick and consists of interbedded bands of kaolinitic brown mudstone and coal plies. In the southern part of the coalfield, the lower section of the seam is higher quality and lower ash. Dendrobium mines the bottom 3.5 m to 4.0 m of the seam, producing hard coking coal for use in steelmaking.

The Wongawilli coal seam varies from 8 m to 10 m thick and consists of interbedded bands of kaolinitic brown mudstone and coal plies. In the southern part of the coalfield, the lower section of the seam …

Application Of Numerical Modeling In Study Of The Behaviour Of Cable Bolts Under Axial Loading, Sina Anzanpour, Naj Aziz, Ameen Topa, Jan Nemcik, Ali Mirzaghorbanali

Resource Operators Conference

Over the past few decades, the rapid development of efficient mathematical algorithms and the increasing availability of powerful computers have made it possible to develop realistic constitutive models. With the development of highly sophisticated constitutive models, the Finite Element Method (FEM) has become an invaluable tool for predicting ultimate loads and the associated failure mechanisms. Consequently, more capable and realistic models can be developed to analyze and design various types of structures. This paper concentrates on the application of FEM model for better understanding of the behaviour of cable bolts under axial loading conditions. A detailed geometry of the pullout …

Slope Stability Prediction Using The Artificial Neural Network (Ann), Al Muhalab Al-Dughaishi, Shivakumar Karekal, Fok Hing Chi Tivive

Resource Operators Conference

Slope failure is a significant risk in both civil and mining operations. This failure phenomenon is more likely to occur during the high rainfall season, areas with a high probability of seismic activity and in cold countries due to freezing-thawing. Further, a poor understanding of hydrogeology and geotechnical factors can contribute to erroneous engineering designs. Several Limit Equilibrium Methods (LEMs) and numerical modelling tools have been developed over the years. However, the highlighted success of the Artificial Neural Networks (ANNs) in other disciplines/sectors has motivated researchers to implement ANNs to forecast the Factor Of Safety (FOS). This paper aims to …

Monitoring And Computational Modelling Of Ventilation And Dust Flow In Development Panel, Ting Ren, Ming Qiao, Jon Roberts, Jennifer Hines

Resource Operators Conference

Exposure to respirable coal dust and respirable crystalline silica dust in underground coal mines is increasingly becoming a concern as a result of the re-emergence of coal mine dust lung disease in New South Wales (NSW) and Queensland. A significant challenge in mitigating dust exposure lies in the better understanding of ventilation and dust behaviour in the gateroad development panels, which can be achieved by a combination of onsite monitoring and computational modelling. Based on site-specific conditions of the underground development panel excavated with a single-pass 12CM30 continuous miner, a three-dimensional computational model was built and verified with onsite dust …

Brittle-Ductile Transition In Coal Pillar Failures, Xiaohan Yang, Mehdi Serati, Paul Buddery

Resource Operators Conference

Factor of Safety (FoS) is the most widely used empirical criterion in coal pillar design. The increased vertical stresses associated with deep mining are resulting in pillar sizes much larger than those used in the development of the empirical strength formula. It is not uncommon to see pillars with over 50 m solid widths based on the established design criteria, which reduces overall reserve recovery and development productivity. Previous research revealed that pillars will transform from brittle to ductile failure with strain-hardening behaviour when their w/h ratio exceeds a certain critical value. However, the actual failure mechanics of pillars with …

3d Rock Failure Modelling Of Pillar Behaviour During Longwall Retreat Into Normal And Angled Design Gas Drainage Stubs, Gaetano Venticinque

Resource Operators Conference

3D Rock failure modelling was used to perform a coal pillar stability analysis comparing normal and angled Gas Drainage Stub (GDS) design during the approach of a longwall. This paper aims to benchmark the response behaviour of rectangle and triangle shape fender pillars respectively formed during longwall retreat into normal and angled GDS designs. The results of this study are intended to provide a general hazard awareness of potential layout/support issues relevant to GDS design rather than providing a unique recommendation or overall mining solution.

Using FLAC3D, computer modelling of the rock failure process simulated pillar loading and pillar failure …

An Approach To Solve Underground Coal Mine Logistics Strain, David Walker, Ernest Baafi, Senevi Kiridena

Resource Operators Conference

There is currently no mechanism for mine management and strategic planners to identify potential future logistical supply chain bottlenecks within a mine plan and address them proactively. By identifying any logistics constraints as early as possible, the best opportunity to rectify the problem at the least expense is realised. The paper discusses a novel approach which has been developed to strategically identify logistics bottlenecks and the impacts that mine planning parameters might have on these at any point in time throughout a life of mine plan. The developed system was applied to a real-world Australian mine with actual logistics tracking …

Reduction Of Fugitive Methane Emissions From Open Cut Coal Mines, Frank Hungerford

Resource Operators Conference

Fugitive coal seam gas emissions from open cut coal mines occur when coal and surrounding strata is exposed and fractured as part of the mining process. This liberates the seam gas confined within the coal seams and is a large contributor to the mining industries greenhouse gas (GHG) footprint. Gas reservoir assessment is required to determine the in situ gas content and composition of the coal seams and carbonaceous strata and to define gas zones likely to be targeted in gas reduction drilling. This paper describes the drilling methods and pre-drainage practices and applications available at access and capture seam …

Proceedings Of The 2023 Resource Operators Conference, Naj Aziz, Kevin Marston, Ali Mirzaghorbanali

Resource Operators Conference

Proceedings of the 2023 Resource Operators Conference. All papers in these proceedings are peer reviewed. ISBN (ebook): 978-1-74128-368-6 ISBN (paperback): 978-1-74128-367-9.

Fighting Mine Fires With A Small Turbine Engine, Mark Kleinhans, Eleonora Widzyk-Capehart, Andre De Kock, Gareth Kennedy

Resource Operators Conference

In the past, exhaust emissions and steam produced from large turbine engines have been successfully used to extinguish fires or early stages of spontaneous combustion of coal in underground coal mines. Extinguishing fires with a turbine engine exhaust emissions and steam eliminates the heat and displaces the oxygen. However, large turbine engines require a pre-existing connection port and the ability to force exhaust gasses throughout the existing underground coal mine ventilation systems and roadways. Simtars is assessing the viability of a smaller turbine engine, with the vision of the exhaust emissions being deployed through existing or newly drilled boreholes in …

Respirable Dust Generation And Mitigation In Australian Underground Coal Mine Development Headings – Applications Of Computational Fluid Dynamics For Respirable Dust Modelling, Kieren Russell, Ting Ren

Resource Operators Conference

Respirable coal and silica dust has long been recognised as causing lung diseases such as silicosis and Coal Worker’s Pneumoconiosis (CWP). These lung diseases and other lung diseases caused from mining are now placed under an umbrella term Mine Dust Lung Disease (MDLD). The re-emergence of MDLD (particularly CWP) in Australia has necessitated extensive research into the field of preventing MDLD.

Computational Fluid Dynamics (CFD) has allowed the industry to model dust flow in underground coal mines, allowing for extensive testing in ventilation flow and other dust mitigation strategies to determine the best practice for individual coal mines. A literature …

Investigating A Potential Geothermal Play In The Southern Sydney Basin, Yangguang Han, Kumari W.G.P., Lloyd White, Dominique Tanner, Titus Murray

Resource Operators Conference

Geothermal energy is a renewable resource that will be part of the world’s transition to clean power production. Different technologies can be utilised to extract heat or produce geothermal-based electricity. The Geological Survey of NSW has identified several regions across the state where there are higher than average geothermal gradients. These regions in the southern Sydney Basin are investigated with the aim of determining if the high temperatures might be related to subsurface rocks with relatively high concentrations of radiogenic isotopes that might create a ‘hot dry rock’ play. Rock properties are tested that would be required to generate a …

Preliminary Studies Of An Energy Efficient Ble Wireless Network For Underground Positioning Systems, Vihanga Peiris, Kai Zhao, Binghao Li, Henry Gong, Aruna Seneviratne

Resource Operators Conference

Positioning is a safety measure and a disaster management method used in the mining industry. Therefore, a positioning system is vital to ensure safety and reduce the risks to life of the workers at mine sites. The major challenge with existing positioning systems located in underground mines is the sending the collected positioning data to the positioning server through the energy-constrained, stationary wireless network nodes. This research is the first to identify the power challenge in sending positioning data in underground mines. By exploiting the mining environment, the authors of this paper propose to use Bluetooth Low Energy (BLE) communications …

Pumpable Two-Part Resin Cable Bolt Bonding Material Tests, Peter Craig, Matthew Holden

Resource Operators Conference

The Australian underground mining industry extensively uses thixotropic cementitious grout as a bonding agent for cable bolts. Grout is very effective as a bonding agent but is prone to issues with consistently achieving full column encapsulation and has operational issues impacting production. An economically viable two-part resin bonding agent is being investigated by Jennmar which offers some operational advantages. This paper explores the bond strength evaluation of the two-part resin against cementitious grout.

Effects Of Rib Distances On Axial Load Transfer Mechanisms Of Fully Grouted Rock Bolts, Amin Motallebiyan, Hadi Nourizadeh, Behshad Jodeiri Shokri, Shima Entezam, Ali Mirzaghorbanali, Naj Aziz, Kevin Mcdougall

Resource Operators Conference

Rock bolt systems are widely used for the reinforcement of underground coal mines after excavation. These systems consist of steel bolts installed in drill holes and encapsulated by resin or grout. The spacing between the rock bolt ribs is one of the factors affecting the axial load transfer mechanisms. Steel rebar with a 16 mm diameter, Stratabinder HS grout, and steel pipes with a diameter of 50 mm were used to simulate the rock bolt system. The distance between the ribs on the rebar was doubled for half of the samples to investigate the effects of rib spacing on the …

Investigating The Effect Of Coal Macerals On The Recovery Rate Of The Flotation Process- A Case Study, Behshad Jodeiri Shokri, Shima Entezam, Alireza Entezam, Ali Mirzaghorbanali

Resource Operators Conference

Alborz-Sharghi coal washing plant is one of the most significant coal producers in Iran, which has a low recovery rate in the flotation process. This paper investigates the effect of coal macerals types on the flotation recovery rate. For this purpose, a comprehensive sampling procedure was conducted on the feed of the flotation system. Afterwards, the required polished sections of the samples were prepared for detecting the macerals. After conducting a series of flotation tests on the samples, the recovery rate results were compared based on detected macerals on the polished sections. The results revealed that the flotation recovery rate …

Shear Strength Properties Of Clean And Clay Infilled Rock Joints: An Analysis Of The Impast Of Moisture Content Under Cnl Conditions, Elizabeth Downing, Ali Mirzaghorbanali, Naj Aziz

Resource Operators Conference

Rock joints are a type of fracture or discontinuity that have little or no movement that is parallel to the plane of fracture caused by forces acting perpendicular to the fractured walls, where the opening of the break is parallel to the face of least resistance. These are common phenomena in geology around the world and range from small scale to tectonic fault lines. The first part of this project focused on the effect of clean rock joints on the shear strength of the joint at normal loads of 100, 300, 500 and 700 kPa. Rock joints leave an opportunity …

Substitution Of Recycled Plastic Aggregates (Rpa) In Concrete And Its Influence On Pullout Capacity Of Mechanical And Chemical Anchors, Raza Akhtar, Graham Skellern, Ali Mirzaghorbanali

Resource Operators Conference

There is a lot of plastic going to land fill or entering environmentally sensitive systems, that could ideally be converted into a form or material that would be considered as a resource. Much of this plastic waste is not suitable for re-cycling or use, where exposed to sun light or weathering elements. Some of these materials have been converted to granular materials and used in sub-soil drainage systems as free draining materials and as substitute for aggregates in concrete pavements. There is significant enthusiasm for utilising ‘environmentally friendly’ construction systems and materials. Unfortunately, that enthusiasm can result in them being …

The Effect Of Changing Confinement Diameter On Axial Load Transfer Mechanisms Of Fully Grouted Rock Bolts, Behshad Jodeiri Shokri, Shima Entezam, Hadi Nourizadeh, Amin Motallebiyan, Ali Mirzaghorbanali, Kevin Mcdougall, Naj Aziz, Karu Karunasena

Resource Operators Conference

This paper aims to study the effect of changing the confinement diameter on the axial load-bearing capacity of rock bolt systems. The diameter of the confinement is monitored in a fully encapsulated rock bolt at day 7 and 28 of grout curing. These particular times were considered critical to demonstrate grout strength when conducting pull-out tests on rock bolt samples. Following this, the samples were cast with a water-grout ratio of 36%, the internal diameters of encapsulation being 23 mm and 50 mm, and the encapsulation length at 50 mm. The results indicated that by increasing the confinement diameter, the …

Investigation Of The Effect Of Using Fly Ash In The Grout Mixture On Performing The Fully Grouted Rock Bolt Systems, Shima Entezam, Behshad Jodeiri Shokri, Hadi Nourizadeh, Amin Motallebiyan, Ali Mirzaghorbanali, Kevin Mcdougall, Naj Aziz, Karu Karunasena

Resource Operators Conference

This paper attempts to reveal the influence of using fly ash in the grout on the axial bearing capacity of fully grouted rock bolts. For this purpose, different fly ash contents, including 1% and 2%, have been applied with Stratabinder HS with a water-to-grout ratio of 30%. Also, after preparing and curing the required samples, the UCS tests were conducted to determine the influence of fly ash on the grout strength. Along with the UCS tests, several pull-out tests were examined by preparing and curing rock bolt samples with steel reinforcement rebars of 16 mm and steel pipes with a …

Movements Of Personnel And Materials In Australian Underground Coal Mines, Chris Harvey, David Walker, Ernest Baafi, Ian Porter, Senevi Kiridena

Resource Operators Conference

With the desire to optimise the development of roadways in underground coal mines as operations expand, it logically followed that any increase in the development rate will require more efficient logistics management, especially the timely supply of roof support materials (bolts, chemicals and mesh) to each active face area. Logistics management in general was not considered as a key issue when initial or long-term planning of an underground coal mine is undertaken. It is traditionally assumed that whatever production targets are set that logistics can keep up or that it is retrospectively managed after an identifiable bottleneck.

Research Into The Selection And Efficiency Of Nozzles For Airborne Dust Suppression, Jon Roberts, Rongfu Liao, Ming Qiao, David Hastie, Peter Wypych

Resource Operators Conference

The suppression of airborne dust is a significant issue within the resources industry that has been highlighted by the re-emergence of lung diseases such as coal workers’ pneumoconiosis and silicosis. A prominent method for the control of airborne dust is the use of water spraying systems to suppress dust and minimise its liberation into the workplace. The challenge with water spraying systems for airborne dust suppression lies largely in the correct selection of nozzles to suit the application. This paper outlines work conducted by the University of Wollongong with funding from the Coal Services Health & Safety Trust to investigate …

Spt-Cpt Correlation In Southeast Queensland, Australia, Yohanne Faivre, Ali Mirzaghorbanali, Hadi Nourizadeh, Behshad Jodeiri Shokri, Kevin Mcdougall, Naj Aziz

Resource Operators Conference

Among the most popular in situ investigation techniques for identifying subsurface strata, cone penetrometer testing (CPT) and standard penetrometer testing (SPT) are employed in geotechnical engineering. In fact, both tests are adopted to correlate a wide range of geotechnical parameters in various design applications. The cost associated with conducting both in situ tests at the same locations often results in one method being chosen over the other. Hence, engineers have to corelate one of the tests’ parameters into the other test using empirical correlation in translating SPT blow counts (SPT-N) into CPT cone tip resistance (CPT-q_c). However, disadvantages …

The Optimisation Of Ground Consolidation Practices In Longwall Mining, Richard Campbell, Ravindu Goonawardene, Ismet Canbulat, Serkan Saydam

Resource Operators Conference

The Australian longwall mining industry spends millions of dollars per year on both proactive and reactive ground consolidation methods from time to time across most of the underground operations currently in production. The design and effectiveness of the applications and products used are often variable and based on past experience at each site or what was considered successful at other sites in similar situations.

This paper discusses the current product testing data and proposes an industry-standard testing regime that will provide mine site-based geotechnical engineers with a standardised set of data for product selection and geotechnical design.

In addition, the …

Deformation Analysis In The Surroundings Of The Roadway Ahead Of Longwall Mining, Staszic-Wujek Mine, Poland, Petr Waclawik, Radovan Kukutsch, Kristyna Schuchova, Jan Nemcik, Andrzej Walentek, Aleksander Wrana, Sahendra Ram, Jiri Korbel

Resource Operators Conference

Accurate knowledge of the stress-strain state in rock mass is absolutely critical to optimise support design. Therefore, the rock mass stresses are often measured for reasons of safety and efficiency in underground mining. Investigation of the rock mass stress is usually carried out by interpretation of the rock mass deformation processes. These can be monitored and measured. The compact conical-ended borehole overcoring (CCBO) probe was used to measure the pre-mining full stress tensor and afterwards three compact conical-ended borehole monitoring (CCBM) probes were installed to continuously monitor stress changes in rock mass ahead of the advancing longwall II/501/C mining seam …

Observations Of Multi-Seam Subsidence At Ashton Underground Mine-2012 To 2022, Ken Mills, Stephen Wilson

Resource Operators Conference

Ashton Underground Mine (Ashton) is an underground longwall mine located northwest of Singleton in the Hunter Valley of NSW. The mine has extracted longwall panels in three seams with mining in a fourth seam planned and each seam progressively deeper than the last. The mining geometry in each of the seams is regular, parallel and either offset or stacked relative to the panels in the seams above. The high-quality survey monitoring dataset available from Ashton provides significant insight into the mechanics of ground behaviour in the multi-seam geometry at this site. This paper presents a summary of the observations and …

Defining Explosion Risk Exclusion Zones Around Coal Mine Openings In Emergency Situations, Alex Remennikov, Edward Chern Jinn Gan

Resource Operators Conference

The risk of explosions in coal mines is an important subject that requires a comprehensive understanding of explosion dynamics, mining operations, and mining safety. Recent spontaneous combustion events in New South Wales (NSW) and Queensland have resulted in mine evacuations due to a Trigger Action Response Plan (TARP) being activated at the evacuation level. A sound basis is required for defining the high-risk working zones, mine operational exclusion zones for both emergency activities and mine design considerations, and public exclusion zones during emergency situations. This paper presents a methodology for predicting and defining explosion risk around the coal mine portals …

Energy Sources Of Rock Burst And The Influence Of The Surrounding Rock Mass, Charlie C. Li

Resource Operators Conference

The kinetic energy for rock ejection in a rock burst event is converted from the strain energy stored in the burst rock, a portion of strain energy released from the surrounding rock mass and a portion of seismic energy transferred from fault-slip seismicity. The kinetic energy is mainly contributed by the burst rock itself in a small-scale strain burst, but the energy released from the surrounding rock mass plays a major role in a large-scale rock burst. Intergranular and extensional cracking is dominating in burst-prone rocks, while in the non-burst-prone rocks the dominating cracking is intragranular and shear. Both the …